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Steel materials and their application: High strength steels for flat products for the automotive industry I (25 June / 14:00 - Room 27)

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25 June / 14:00 - Room 27:

A component oriented method for the examination of toughness values of sheet metals

M. Henrich
(RWTH Aachen University, Germany)

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Title: A component oriented method for the examination of toughness values of sheet metals


Author:
M. Henrich

Company:
RWTH Aachen University, Germany

Co-Authors:
M. Könemann, S. Münstermann

Abstract:
The resource-saving use of construction materials has led to the development of high-strength steels in recent years. The aim is to minimize the sheet thickness of components without impairing the properties of the structures. Particularly in the automotive industry, the use of high-strength steels contributes to achieving increasingly restrictive regulations. So far, no suitable examination method has been available to examine the impact toughness of sheets with low thicknesses. At the same time, it is known from the Charpy-V-notch test that this test provides values that are only of limited informative value for the final use in the component. Therefore, the article presents the tensile impact test, which can be used for toughness testing of thin sheets. Furthermore, a method based on this test will be presented, which allows the examination of the material toughness according to the component. Numerical simulations can be used in this method to identify highly stressed points and to define stress states that characterise these points. In a sample catalogue created for the tensile impact test, a sample can then be selected which is congruent with the stress state in the component. Thus, the potential of the material can be tested quickly and without great effort. The article shows the test procedure and presents the sample catalogue. The embedding of the test in simulation-based investigations is also presented.

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25 June / 14:20 - Room 27:

Effect of alloying elements on mechanical properties and microstructure of modified TRIP Steels

K. Yang
(China Steel Corporation, China)

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Title: Effect of alloying elements on mechanical properties and microstructure of modified TRIP Steels


Author:
K. Yang

Company:
China Steel Corporation, China

Co-Authors:
J. Tu, L. Chiang, W. Cheng

Abstract:
Recently, extensive efforts were paying attention to develop advanced high strength steels (AHSS) to improve combinations of strength and elongation for lightweight and crashworthiness of vehicle. Formability of dual phase steel is significantly limited with being subjected to severe cold forming while the strength reaches the grade of 980MPa. The modified TRIP (TRansformation Induced Plasticity) steels with the same grade of 980MPa provide higher elongation to improve the formability. In this research, the base Fe-C-Mn-Si steel with various additions of Si, Mn and Al was applied. The influence of these alloying elements on the phase transformation further affecting the mechanical properties and microstructure after experiencing different annealing treatments was investigated. These microstructures were analyzed via Optical Microscope (OM), Scanning Electron Microscope (SEM) and X-Ray Diffractometer (XRD). The suitable chemical composition has been developed with the appropriate modified TRIP process to provide steel with tensile strength and elongation over 980MPa and 20%, respectively. The mechanical properties of this developed modified TRIP steel meet the requirement of high formability keeping high strength of 980MPa level.

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25 June / 14:40 - Room 27:

Super-hard steels for highly stressed components

A. Kleemann
(MFPA Weimar, Germany)

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Title: Super-hard steels for highly stressed components


Author:
A. Kleemann

Company:
MFPA Weimar, Germany

Co-Authors:

Abstract:
Lightweight construction and resource efficiency continue to be the focus of industry as important building blocks for meeting ever-increasing environmental demands. It is therefore extremely important for innovation-driven branches of industry such as automotive and mechanical engineering to build components that becomes lighter and lighter by using modern high strength and ultrahigh-strength steels. In order to use these steels, the properties of these steels must be known. Especially for the design against fatigue, extensive knowledge of the cyclic material properties and the transferability as well as a deep understanding of the damage mechanisms are required. On the basis of extensive experimental investigations and analytical work, it has been possible to create basic knowledge for manufacturing components from high-strength steels. The experimental database comprises high-strength and ultrahigh-strength steels of different strengths, alloying concepts and purity grades up to 2400 MPa tensile strength. Fatigue tests were carried out at various stress ratios from LCF to fatigue strength. The experiments were accompanied by microstructural and fractographic investigations to gain knowledge of the microstructure-property correlations. In connection with transferability, influencing factors such as residual stresses, roughness, mean stress, notch effect, stress gradient and surface layer treatment were assumed. Experimental investigations on samples and components similar to components serve to validate the design methods. The report shows the enormous lightweight construction potential for serial components using high-strength steels and validated design methods and aims to contribute to the increased use of these steels.

Steel materials and their application: High strength steels for flat products for the automotive industry II (25 June / 15:50 - Room 27)

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25 June / 15:50 - Room 27:

New quasi single-phase microalloyed bainitic precision strip qualities

M. Nagel
(Thyssenkrupp Hohenlimburg GmbH, Germany)

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Title: New quasi single-phase microalloyed bainitic precision strip qualities


Author:
M. Nagel

Company:
Thyssenkrupp Hohenlimburg GmbH, Germany

Co-Authors:
H. Bröker, A. Tomitz, M. Kaizik, S. Kovacs, G. Gevelmann, A. Höhne

Abstract:
The development and industrial application of hot rolled steel grades is accelerated by the automotive industry's focus on cost reduction and lightweight design. Additionally modern part designs require more sophisticated forming und cutting properties of cold formable steel grades. thyssenkrupp Hohenlimburg GmbH developed a new quasi-single-phase bainitic steel grade family. These hot rolled bainitic steels are based on micro-alloyed steel concepts and can be produced in different strength classes, starting from min. 600 MPa up to min. 1000 MPa, thus extending the already available strength class of conventional micro-alloyed steel grades. The paper presents the production and special features of this new steel grade family. The steel families low carbon equivalents leading to good overall weldability and their specific joining properties according to tests performed by SEP 1220 are shown. The reduced edge crack sensibility of punched edges is demonstrated by the hole expansion test. The steels low temperature toughness and crash behavior are demonstrated. Favorable fields of use and application examples in automotive components of these steel grades are described.

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25 June / 16:10 - Room 27:

CELES EcoTransFlux

E. Patard
(Fives Celes, Germany)

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Title: CELES EcoTransFlux


Author:
E. Patard

Company:
Fives Celes, Germany

Co-Authors:

Abstract:
For galvanizing and annealing lines for AHSS and similar grade steels, conventional heating rates of around 70°C/s are often insufficient for complex heating and cooling cycles required and thus the last state-of-the-art induction heating technology, with transverse flux rather than conventional longitudinal flux, offers a real and proven alternative for very rapid heating with up to 400°C/s. By injecting up to 2MW/m2 of energy into a strip in a homogeneous manner, it can be heated well beyond Curie point at 760°C from early stage of the process and even for non-magnetic steels. This paper describes the latest technological developments of the CELES EcoTransFluxTM technology, as the culmination of 15 years R&D; technological challenges faced and their solutions will be presented with feedbacks from first industrial installations.

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25 June / 16:30 - Room 27:

Instrumented indentation technique and its application on determination of local material properties of high strength steels

E. Javaheri
(Fraunhofer Institute for Production Systems and Design Technology, Germany)

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Title: Instrumented indentation technique and its application on determination of local material properties of high strength steels


Author:
E. Javaheri

Company:
Fraunhofer Institute for Production Systems and Design Technology, Germany

Co-Authors:
M. Rethmeier, B. Graf, A. Pittner

Abstract:
Knowledge of the mechanical properties of steel materials such as strength or ductility is a subject of high interest for the majority of companies in both metal processing and production, as well as for the users and developers of numerical simulation software. The material parameters can be obtained by performing the tensile test on the samples made from a part of a component. In some cases, it is highly expensive to produce the tensile specimens especially for the welded steel structures, which contain different type of microstructure such as weld seam or heat affected zone in an extremely small area. Therefore, a novel method is described in this paper to determine the material parameters of high strength steel structures locally and without any additional effort to perform the tensile test. In this method, instrumented indentation test (IIT), an indenter is pushed on the flat surface of a specimen in a certain period of time and simultaneously the applied force and the corresponding indentation path are measured. The data related to the force-indentation diagram is given as input to a trained artificial neural network (ANN) to obtain the material parameters such as strain hardening parameters as outputs. The ANN was trained in this work by generating large qualitative data sets with numerical simulation of the IIT procedure. The simulation was run several times with the different material model parameter sets to generate the numerous force-indentation diagrams as the inputs of ANN. Then, the trained ANN was validated by performing the IIT on dual-phase steels and comparing the obtained material parameters from ANN with tensile test results. Consequently, the mechanical properties of high strength steels and the welded joints can be determined by performing the IIT and evaluating the resulting data by the validated ANN.

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25 June / 16:50 - Room 27:

Development of alloying concepts and process strategies for the production of safety-relevant lightweight body components with increased residual formability in press hardened condition

Y. Sparrer
(Integrity of Materials and Structures, Steel Institute; RWTH Aachen University, Germany)

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Title: Development of alloying concepts and process strategies for the production of safety-relevant lightweight body components with increased residual formability in press hardened condition


Author:
Y. Sparrer

Company:
Integrity of Materials and Structures, Steel Institute; RWTH Aachen University, Germany

Co-Authors:
K. Bissa, A. Tenié, J. Lian, W. Bleck, S. Münstermann

Abstract:
New emission standards, stricter environmental requirements, and increasing fuel consumptions have led to a change of mindset in the automotive industry within the last years. In order to reduce the CO2 footprint of the vehicles, car manufacturers focus on decreasing the vehicle weight by adopting the lightweight design concept of the bodywork components. In order to fulfill these demands, a wide range of high-strength steels has been developed within the last years, e.g. dual-phase (DP) steels, transformation-induced plasticity (TRIP) steels, etc. However, In addition to sustainability, passenger safety also plays an important role in the design of novel cars. Therefore, current research deals with the development of quenching & partitioning (Q&P) steels that provide promising material properties for the use in safety-relevant bodywork components, e.g. the B pillar. In this study, a 0.2C-2.0Mn-0.3Si steel and a 0.2C-4.5Mn-1.7Si steel were processed following the DP and Q&P heat treatment scheme, respectively. By varying the process parameters of the different heat treatments, the microstructure and thus the mechanical properties of the steels can be expediently modified. In order to investigate the influence of the selected process parameters, quasi-static tensile tests were conducted and compared to the results of a press hardened 22MnB5 steel (reference material). Subsequently, the microstructure and mechanical properties of the different steels are discussed. It can be shown that the Q&P steel offers promising mechanical property profiles, while the DP steel does not lead to an improvement of the mechanical properties compared to the reference material. Eventually, by applying a custom-made Q&P heat treatment the total elongation was doubled (from 6-8% to 12-19%) while maintaining the strength level (1300-1500 MPa) compared to the reference material.

Steel materials and their application: Advanced High strengths and special steels, characterization and modeling I (26 June / 09:00 - Room 14)

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26 June / 09:00 - Room 14:

Numerical prediction of damage in punching process using shear modified Gurson model

H. Janarthanam
(Fraunhofer Institute for Mechanics of Materials, Germany)

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Title: Numerical prediction of damage in punching process using shear modified Gurson model


Author:
H. Janarthanam

Company:
Fraunhofer Institute for Mechanics of Materials, Germany

Co-Authors:
S. Sommer, F. Huberth, E. Carl, J. Preußner

Abstract:
Punching process is deformation intensive and alters the material properties on the punch surface and in its vicinity due to damage and plastic flow. Studies on micrographs of various punched samples have shown that in punching process tensile and shear damage mechanisms prevail. In addition, punching process involves high velocity deformation which influences the plastic hardening and damage due to strain rate effect. Also, at high strain rates adiabatic shear bands develop in polycrystalline materials which lead to thermal softening. Here, numerical prediction of deformation, damage and failure during the punching process of S500MC [DIN/EN - QStE 500 TM] structural steel is investigated. The sound material is modelled using a shear modified GTN model as proposed by Nahson and Hutchinson. The evolution of damage is described by void volume fraction in the material model, where the voids nucleate and grow due to plastic deformation. The model is further phenomenologically extended using Johnson-Cook hardening law to account for the strain rate and temperature effect. To describe the final coalescence/failure of voids, a combination of coalescence criteria as proposed by Thomason, and Embury are used. To calibrate the material model, a series of tension, torsion and torsion-tension experiments on smooth round bars and notched round bars at quasi-static loading are conducted. The tensile experiments are also performed at nominal strain rates of 8.33s^(-1) and 83.33s^(-1). A shear tensile specimen is used to quantify adiabatic heating and failure under shear dominated loading, where the temperature in the shear zone is monitored using IR camera. The numerical results show that the phenomenological extension for hardening and coalescence are in good agreement with the experimental results. The punching process is later simulated using the calibrated model and the numerical prediction of residual stresses are compared to the experimentally measured values.

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26 June / 09:20 - Room 14:

Development of API X60 pipeline steel for sour service with lower Manganese

H. Al-Jabr
(SABIC, Saudi Arabia)

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Title: Development of API X60 pipeline steel for sour service with lower Manganese


Author:
H. Al-Jabr

Company:
SABIC, Saudi Arabia

Co-Authors:
M. Patil, S. Rehman, Y. Al-Zain

Abstract:
Pipelines have an exceptional importance in oil and gas industries as several thousand kilometers of pipelines are commissioned every year. With continuous exploitation of energy resources, the demand for high strength pipelines steel for sour gas services is considerably increasing. This study investigates the effects of manganese addition to develop API X60 pipe steels for sour service on the susceptibility to hydrogen induced cracking (HIC). Two API-X60 pipeline steels for sour service application were investigated in this work. One steel with 1.0% manganese (high Mn) and the other with 0.8% manganese (low Mn). The low Mn steel contained slightly higher amount of other strengthening elements to compensate for the strength drop due to the reduction of Mn content. Both steels achieved the API requirement for mechanical properties for X60 and passed the requirements of NACE TM 0284 standard for HIC resistance. Cracks were not found in the tested HIC samples for the low Mn steel. However, some samples of the high Mn alloy exhibited cracking within the limits specified by the NACE standard. The cracks were present in the center width of the coils at mid thickness. The microstructures were similar for both chemistries and consisted of fine polygonal ferrite with low volume fraction of uniformly dispersed pearlite. However, centerline segregation was more pronounced in the high Mn steel compared to the low Mn steel. Based on SEM results, the Mn index, defined as the ratio of Mn content between the segregated region and the matrix, was higher in the high Mn steel reaching to 1.8 in some samples, especially in the cracked samples. Whereas the Mn index was always below 1.3 for the low Mn steel. The reduction in Mn content suppressed the formation of hard bainitic structure in the mid-thickness and hence increased the resistance to HIC.

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26 June / 09:40 - Room 14:

Influence of the alloy composition of an air-hardened, martensitic forging steel on the mechanical and cyclic material behavior

T. Schmiedl
(Technische Universität Darmstadt, Germany)

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Title: Influence of the alloy composition of an air-hardened, martensitic forging steel on the mechanical and cyclic material behavior


Author:
T. Schmiedl

Company:
Technische Universität Darmstadt, Germany

Co-Authors:
A. Gramlich, S. Schönborn, R. Wagener, T. Melz, W. Bleck, T. Melz

Abstract:
New steel concepts enable an improved lightweight design with enhanced structural durability of cyclic loaded forged safety components in comparison to conventional quenched and tempered (Q&T) steels. By using the new steel concepts a two-step heat treatment for adjusting the material properties should not be necessary. This leads to a shorter and energy saving process route which reduces the production costs. Overall, the implementation of new steel concepts will increase the competiveness of the German steel and forging industries. For new steel concepts like precipitation hardened ferritic-perlitic forging steels a one-step heat treatment is sufficient to achieve the required material properties. In case of the recently developed bainitic forging steels there is no need for an additional heat treatment as long as cooling from the forging temperature to room temperature is controlled. New air-hardened, martensitic forging steels offer a great opportunity for replacing the conventional Q&T steels (e.g. 42CrMo4) because a two-step heat treatment and a precise cooling are not required. The aims of these investigations are to achieve size independent mechanical/cyclic properties and to increase/maintain these properties in comparison to the conventional Q&T steel 42CrMo4. To achieve a homogenous microstructure even for large parts the alloy composition is varied and several material concepts are created. The microstructure is characterized with regard to the homogeneity by light and scanning electron microscopy and the mechanical properties are determined by tensile tests, Charpy V-notch tests and hardness measurements. Furthermore, Incremental Step Tests with unnotched specimen are performed to determine the cyclic stress-strain behavior, which are compared with the quasi-static material properties. Fatigue tests with notched specimen are used to determine the fatigue strength in the high-cycle fatigue regime. Finally the influence of the alloy composition on the mechanical and cyclic properties is discussed.

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26 June / 10:00 - Room 14:

Phase transformation modeling of AISI 4140 steel rods after hot rolling and during direct quenching

A. Meysami
(Golpayegan University of Technology, Iran)

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Title: Phase transformation modeling of AISI 4140 steel rods after hot rolling and during direct quenching


Author:
A. Meysami

Company:
Golpayegan University of Technology, Iran

Co-Authors:

Abstract:
Direct quenching (DQ) process is an appropriate method in steels heat treatment field after hot rolling. During direct quenching of steel components, obtaining the desired distribution of microstructure would satisfy production goals and reliable service performance. In this study, a Finite Volume Model (FVM) based model has been developed to describe diffusional and diffusionless transformation in AISI 4140 steel rods during direct quenching. In non-isothermal quenching process, subdivision of the cooling curve into various small isothermal steps was introduced with the help of various time–temperature–transformation (TTT) diagrams of AISI 4140. In addition, Scheil’s additive rule and Johnson–Mehl–Avrami–Kolmogorov (JMAK) equation were also solved. On the other hand, Koistinen and Marburger’s equation was used to model the diffusionless transformation. This model could predict microstructure evolution and volume fraction of each phase during process, so that it permits the progress prediction of ferrite, pearlite, bainite, martensite and retained austenite transformation simultaneously. To verify the model results, several experiments have been performed on a physical model. After direct quenching of AISI 4140 rods with radius 55 mm, volume fraction of retained austenite and other phases including ferrite, bainite and martensite have been measured through magnetization and XRD methods. There was a good agreement between numerical and experimental results.

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26 June / 10:20 - Room 14:

In-line characterisation of the austenite level to ensure the mechanical properties along the coil

O. Herbiet
(CRM Group, Belgium)

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Title: In-line characterisation of the austenite level to ensure the mechanical properties along the coil


Author:
O. Herbiet

Company:
CRM Group, Belgium

Co-Authors:
G. Monfort, G. Moreas

Abstract:
During the manufacturing of the modern high strength steels, it is very important to know the austenite level compared to ferrite at given positions in the line during the steel production. Indeed, ensuring the constancy of the austenite fraction is mandatory for the constancy of the mechanical properties of the final product. There are several positions in the line where it is essential to know the fraction of austenite, namely for example, the exit of zinc bath in steel galvanising lines, several intermediate locations in the annealing furnaces and the exit of steel annealing lines, the exit of the steel hot rolling mills on the run-out table. These positions induce many constraints which are very difficult to address. Indeed, this new sensor aims to overcome the limitations of current measurement devices of the austenite level in steels. In particular, the sensor allows the measurement at low or high temperature of the steel strip (850°C). It allows the measurement at a distance of several tens of millimetres of the strip while keeping a sufficient sensitivity. The measurement is not influenced by the vibrations of the strip as well as by abrupt change of the distance sensor – strip. This sensor is also able to work above and below the Curie temperature. The modularity of this sensor allows characterising not only the full width but different zones on the width and, particularly, the sides and borders of the strip which can show different properties due to different behaviour during the heating or cooling phase.

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26 June / 10:40 - Room 14:

Development and application of high strength and corrosion resistant roll-bonded checkered plate

B. Yan
(Baosteel Central Research Institute, China)

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Title: Development and application of high strength and corrosion resistant roll-bonded checkered plate


Author:
B. Yan

Company:
Baosteel Central Research Institute, China

Co-Authors:

Abstract:
Abstract Checkered plate, which is also known as floor plate, has a raised pattern that provides excellent skid resistance for a wide range of applications, such as flooring, walkways, platforms, stair treads, covers, etc. As one of most common used products, carbon steel checkered plate needs high cost in corrosion resistance. Although stainless steel checkered plate meets the requirements of corrosion resistance, it is also hard to provide a highly comprehensive performance for its low mechanical properties, which mean higher thickness, higher weight, lower stability of structure. Combined the advantages of stainless steel and carbon structural steel, one kind of SUS316L-BDT01 or SUS304L-BDT01 roll-bonded clad checkered plate with high performance in skid resistance, high strength and corrosion resistant is developed. The metallography shows cladding interfaces are very good. The yield strength, tensile strength and elongation from tensile tests are significantly better than the other kinds of checkered plates. Both external and internal bending at room temperature can be done successfully done without any cracks. Therefore, roll-bonded clad checkered plate shows superior performance in microstructure, strength, ductility and workability. It will meet the requirements of modern factories and has a broad market prospect. Through a case of the application on a pulverized coal injection platform in an iron-making plant, the processing and installation of this kind of material were introduced. After two years tracking on the platform, the product shows high performance in corrosion resistance and mechanical properties. Keywords Clad rolling, roll-bonded clad checked plate, microstructure, mechanical properties

Steel materials and their application: Advanced High strengths and special steels, characterization and modeling II (26 June / 11:20 - Room 14)

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26 June / 11:20 - Room 14:

Study of heat transfer distribution during plate heat treatment

P. Kotrbacek
(Brno University of Technology, Czech Republic)

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Title: Study of heat transfer distribution during plate heat treatment


Author:
P. Kotrbacek

Company:
Brno University of Technology, Czech Republic

Co-Authors:
M. Pohanka, M. Chabicovsky

Abstract:
The paper is focused on the experimental research of the heat transfer and boundary conditions of the plate cooling. Real boundary conditions are necessary for the numerical simulation and optimization of the cooling process. Especially in the field of the heat treatment, the knowledge of realistic boundary conditions is necessary. For this purpose, a special methodology was developed. The input data for the inverse task are obtained from laboratory experiments. The main advantage of this method is the achievement of required material and mechanical properties. Heat treatment allows a manufacturing process which can improve product performance by increasing steel strength, hardness, and other desirable characteristics.

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26 June / 11:40 - Room 14:

Influence of processing parameters on recrystallization behavior for API-X70 steel

A. Alshahrani
(SABIC, Saudi Arabia)

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Title: Influence of processing parameters on recrystallization behavior for API-X70 steel


Author:
A. Alshahrani

Company:
SABIC, Saudi Arabia

Co-Authors:

Abstract:
Softening mechanisms including dynamic recrystallization on thermo-mechanical processing of API have crucial effect on resultant microstructure, and consequently the mechanical properties. The influence of deformation temperature and strain rate on dynamic recrystallization (DRX) behavior and mechanical properties of API-X70 were studied using Thermo-mechanical simulator (Gleeble). DRX parameters including critical and peak strains for the deformation temperatures of 950C, 1025C and 1100 C with strain rate of 0.1and 5 s_1 were determined. Peak stresses and strains relationship with the Zener–Hollomon parameter was determined. Moreover, the volume fraction of dynamically recrystallized fraction was computed and the DRX map for the selected steel was developed. The DRX was found to be starting earlier with higher strain rate and lowering deformation temperatures.

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26 June / 12:00 - Room 14:

Cleavage fracture modeling of a S355 construction steel using a modified Gurson-Tvergaard-Needleman model (GTN)

J. Langenberg
(RWTH Aachen University, Germany)

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Title: Cleavage fracture modeling of a S355 construction steel using a modified Gurson-Tvergaard-Needleman model (GTN)


Author:
J. Langenberg

Company:
RWTH Aachen University, Germany

Co-Authors:
S. Münstermann, K. Markus

Abstract:
Damage mechanical simulations are a great tool to predict the mechanical behavior of construction steels and can be a great support in the design of steel constructions. Abusing cleavage fracture is thereby a crucial aspect in the design of multiaxially loaded components. So far, cleavage fracture in Gurson models is mostly simulated by a combination with a Beremin model as a post processor. Unfortunately, the Beremin model isn´t able to take stress triaxialities and the lode angle into account, two parameters which are critical to adequately depict cleavage fracture. The extended Orowan cleavage fracture criterion defines fracture in dependence of critical stress- and strain states for every element of the FEA calculation. By using this single element formulation, cleavage fracture in less ductile steels can be very well predicted. However, the extended Orowan criterion is not implemented in any Gurson model yet. The evaluation and implemention of a suitable cleavage fracture criterion for the used GTN model to predict lower shelf behavior in Charpy impact tests will be the aim of this work. Thus, the extended Orowan criterion given by He was implemented into the underlying GTN formulation and a summary of the implementation technique will be given. Regarding the material properties the examined S355 steel shows a very high ductility even at cryogenic temperatures under low triaxialities. Thus, the discussion of the influence of different stress triaxialities and plastic strains becomes one of the most important aspects of this study. Hence, an adequate experimental calibration scheme, including the calibration of a temperature dependent function for the flowcurve, according to its change in stress at low temperatures, turns into another central feature to achieve adequate results.

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26 June / 12:20 - Room 14:

Fatigue strength of laser welded butt joints made of high-strength fine-grained structural steels for the application in crane structures

B. Möller
(Fraunhofer Institute for Structural Durability and System Reliability, Germany)

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Title: Fatigue strength of laser welded butt joints made of high-strength fine-grained structural steels for the application in crane structures


Author:
B. Möller

Company:
Fraunhofer Institute for Structural Durability and System Reliability, Germany

Co-Authors:
B. Seyfried, R. Wagener, P. Knödel, T. Melz, T. Ummenhofer

Abstract:
High-strength steels are a convenient choice for the lightweight design of cyclic highly loaded structures. The exploitation of the ultra-high-strength fine-grained structural steels’ potential is not possible in the design phase, due to strength limitations caused by application in load-carrying welds, e.g. transverse butt joints. Within crane construction, usually gas metal arc welding (GMAW) is used to manufacture welded joints. Latest developments tend to employ laser beam and laser hybrid welding to cope with increasing demands for cost-efficiency of the manufacturing processes and further increase of the welds’ strength. The application of modern beam welding processes has the aim of paving the way to a fatigue design in highly stresses areas. Therefore, the present investigation focuses on laser beam and laser-MAG hybrid butt welds made of the ultra-high-strength fine-grained structural steels S1100QL and S1300QL. The laser beam welded butt joints made of S1100QL show a high fatigue strength with a stress amplitude of 142 MPa at 2 million cycles to failure with a survival probability of 50 % and a flat slope of the S-N curve. The results are far above the highest fatigue classes of common recommendations for welded joints. Butt joints made of S1300QL have a similar weld appearance, but show a lower stress amplitude of 102 MPa compared to S1100QL butt welds. The reason can be traced back to the welding processes’ individual effect on the specific microstructure. Fatigue tests on laser-MAG hybrid butt welds result in a considerably lower fatigue strength for both materials, which is in the range of manually MAG welded butt joints. Finally, a linear damage accumulation according to Palmgren-Miner elementary is applied to show the application of the theoretical damage sum of 1 for a fatigue life estimation.

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26 June / 12:40 - Room 14:

Replacement of molybdenum by tungsten of Cr Mo V steel

S. Ghali
(Central Metallurgical Research & Development Institute (CMRDI0), Egypt)

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Title: Replacement of molybdenum by tungsten of Cr Mo V steel


Author:
S. Ghali

Company:
Central Metallurgical Research & Development Institute (CMRDI0), Egypt

Co-Authors:
H. El-Faramawy, A. Ahmed

Abstract:
This article aims at investigation the effect of partial and total replacement of molybdenum by tungsten in CrMoV steel on phases. Three steel grades were produced in induction furnace with different molybdenum and tungsten contents. The chemical compositions of three steel grades are: 8.47%Cr, 0.512%Mo, 0.244%V and 0.12%C; 9.17%Cr, 0.284%Mo, 0.245%W, 0.201%V and 0.13%C; 11.16%Cr, 0.569%W 0.30 %V and 0.11%C. Forging process were carried out in temperature range 950 oC – 1100 oC, followed by air cooling. All steel grades were austenized at 1050 oC for one hour followed by water quenching and were tempered at 700 oC for 2 hours. Optical microscope, Scanning Electron Microscope (SEM), and EDX were used to investigate the microstructure and precipitated phases after austenization and tempering process. Thermo-Calc program was used to predict the phases which may be formed. The obtained results of software were interpreted with the experiment results. The results showed that replacement of molybdenum by tungsten has effect to certain extinction on type of precipitates

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26 June / 13:00 - Room 14:

Analytical and simulation-based description of separations in modern high-toughness steels

D. Lenz
(RWTH Aachen University, Germany)

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Title: Analytical and simulation-based description of separations in modern high-toughness steels


Author:
D. Lenz

Company:
RWTH Aachen University, Germany

Co-Authors:
S. Münstermann, M. Könemann, D. Li

Abstract:
The resistance against continuous cracks while guaranteeing crack arrest is one of the most important safety requirements for gas transporting pipelines. In order to meet these requirements, the European steel industry has developed pipeline steels with excellent toughness properties. However, the potential of these modern and extremely tough materials cannot be fully exploited yet. This is due to the fact that phenomena are observed in the toughness characterization which are still unknown in steels with moderate toughness. One of these phenomena are separations (fracture surface tearing). Due to transverse tensile stresses, which result from a occuring transverse elongation obstruction, the fracture surface is ruptured perpendicular to the main crack. When dealing with separations, there are still uncertainties regarding the effects on the component behaviour. The purpose of this study is to investigate the reasons for the occurrence of separations and the factors influencing them. Since this phenomenon occurs primarily in toughness characterization, the main focus is on the Charpy-V-notch test. Possible influencing factors are the strain rate, the temperature or the type of load. For the influencing variables, tests such as the dynamic tensile test or the 3-point bending test are investigated. The metallographic investigation of the fracture surfaces is applied to find the cause of separations and improve the understanding of its origin. Furthermore, a concept is derived which can depict separations by FEM simulations. The development of a failure criterion which can simulate separations is paramount for this study. These approaches extend the understanding of separations and show to what extent the results can be transferred to the real component.

Steel materials and their application: Hot formed steel parts for the automotive industry (26 June / 14:00 - Room 14)

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26 June / 14:00 - Room 14:

Design of safety relevant steel components considering local damage evolution

M. Hell
(Fraunhofer Institute for Structural Durability and System Reliability, Germany)

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Title: Design of safety relevant steel components considering local damage evolution


Author:
M. Hell

Company:
Fraunhofer Institute for Structural Durability and System Reliability, Germany

Co-Authors:

Abstract:
One of the main applications for forged steel components are safety relevant parts, e.g. in the chassis structure of passenger or commercial vehicles. In order to stay competitive on the market, ever-growing demands for weight reduction, cost savings and increased product reliability have driven the development of a huge variety of new steel grades, for example precipitation hardened ferritic-pearlitic steels, TRIP-Steels, etc., as well as enhanced production technology in the past years. Yet, the full potential of new materials and production routes can only be exploited if the improved material properties and process features are implemented already during early design phases. Under service load-time functions, containing loads originating from the regular use of the component as well as overloads induced by special duty or misuse, a safety relevant component is weakened constantly by microscale fatigue phenomena, which accumulate in the component, before macroscopic damage is noticeable. Although the mechanisms of the localized fatigue phenomena are governed by the local elasto-plastic cyclic deformation, the vast majority of state-of-the-art design methods still focus on estimating the damage accumulation with respect to the external loading only. Those methods lack the ability to consider local fatigue mechanisms explicitly and may not unlock the full potential of new steel grades and production technology regarding damage tolerance and reliability. In order to be able to implement the material behaviour properly and enable reliable statements about the fatigue strength under service loading, a design approach is required which allows the evaluation of the local damage evolution. The presented work therefore focusses on a fatigue design approach which allows the design of components under service loading by evaluating the local damage evolution using an elasto-plastic material model and different transfer methods in order to consider e.g. manufacturing process effects or size effects on fatigue life and reliability.

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26 June / 14:20 - Room 14:

Development of a press hardened steel with high strength and high ductility

R. Ge
(Wuhan Branch of Baosteel Central Research Institute, China)

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Title: Development of a press hardened steel with high strength and high ductility


Author:
R. Ge

Company:
Wuhan Branch of Baosteel Central Research Institute, China

Co-Authors:

Abstract:
Increase in the demand for high strength combined with high ductility by the automotive and other industries has led to the development of advanced high strength steels. The present work is aimed at exploring one-step quenching press hardened steel. Three types of steels with varying Aluminum contents (1, 2 and 3wt%) and manganese content of 5wt% were considered in this study. Different heat treatment have been carried out on these steels. The mechanical properties were assessed and retained austenite fractions measured. The results show that the press steel with Aluminum content of 2.0 wt% and heated at 800 oC exhibited remarkable property with the ultra tensile strength of 1450Mpa and total elongation of 11%.

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26 June / 14:40 - Room 14:

An original press hardening steel with excellent application properties produced by Compact Strip Process technology

H. Wang
(Baosteel/ Wuhan Branch of Baosteel R&D Center, China)

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Title: An original press hardening steel with excellent application properties produced by Compact Strip Process technology


Author:
H. Wang

Company:
Baosteel/ Wuhan Branch of Baosteel R&D Center, China

Co-Authors:

Abstract:
Hot Stamping Process can minimize some problems during the cold forming of Advanced High Strength Steels (AHSS) such as stretching capacity, spring-back, and dimensional accuracy, and today the Press Hardening Steels (PHS) for hot-forming is widely used to produce some automotive parts with relatively complex shapes such as A-pillars, B-pillars, front/rear side members, etc. Thin Slab Continuous Casting and Direct Rolling (TSCCDR) Process is one kind of green and low cost process on the basis of its compact process characteristics. In this paper, an original Pressing Hardening Steel is developed in Compact Strip Process (CSP) mill in WISCO Ltd. China. The application properties of the new PHS by CSP are studied and the results shows that the new PHS has a good spot and laser weld capability, well painting properties, lower hydrogen induced delayed cracking susceptibility. The original HPS has been successfully applied in some B-pillars, A-pillars and cross members.

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26 June / 15:00 - Room 14:

Lightweight design in agricultural machinery through the use of higher-strength steels

A. Siegrist
(Hochschule Osnabrück, Germany)

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Title: Lightweight design in agricultural machinery through the use of higher-strength steels


Author:
A. Siegrist

Company:
Hochschule Osnabrück, Germany

Co-Authors:
C. Schäfers

Abstract:
Lightweight design in agriculture is more necessary than in past. Due to the steady increasing population and related the demand of foods, agricultural machines have to be more efficient.The development of the necessary machines collide with limits of legislation. As well on the Roads as on fields the achselloads and ground pressure are limited. Primary motivation of lightweight design in agriculture are based on stated facts. Therefore as well constructiv as material aspects provide in unison the necessary Weight reduction. In addition fatique analyse should be included in product develpment process. The publicly funded research project includes on the one hand the theoretical approaches to the optimization of a lightweight construction, as well as the practical implementation of the measures on a spray boom. In the foreground of the development is the use of high-strength steels, which allows a significant increase in the allowable stress. At the beginning of the research project, an FE model was constructed from the CAD data and potential measuring points determined. On the basis of the determined measuring points the measuring technology was mounted on the test machine. Subsequently, the stresses which act on the linkage were determined metrologically by means of operating runs. The evaluated data from the test drives serve as a basis in the simulation-based optimization steps. The weight optimization was not only achieved by reducing the wall thickness when using high-strength steels, but was achieved by constructive change both in shape and in the kinematics used. The result shows the successful implementation of the project. Due to the structural redesign of the individual segments, the substitution of the material by a higher-strength steel as well as the change in the kinematics, a weight saving of 36% could be achieved.

Steel materials and their application: High strength steels for bars and wire rods for automotive and engineering industry I (26 June / 09:00 - Room 15)

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26 June / 09:00 - Room 15:

Influence Of patenting heat treatment process speed on high carbon steel wire microstructure and mechanical properties

S. Esen
(Celik Halat ve Tel Sanayii A.S., Turkey)

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Title: Influence Of patenting heat treatment process speed on high carbon steel wire microstructure and mechanical properties


Author:
S. Esen

Company:
Celik Halat ve Tel Sanayii A.S., Turkey

Co-Authors:
M. Akar, A. Tığcı, C. Bilen

Abstract:
During the wire drawing process, high carbon steel wires exposed to strength due to mechanical deformation and dislocation action gain toughness with patenting heat treatment. The main goal of the patenting heat treatment is to obtain a fine perlitic microstructure. In this direction, the wires are heated to the austenitizing temperature and cooled under control to the temperature specified in the TTT diagrams. Heat treatment in industrial patenting processes is associated with more than one parameter. In this study, the process speed is examined among the effective parameters. 3,50 mm wires with carbon composition of 0,70%, 0,75% and 0,83% have been investigated the effect of different process speeds at constant heating and cooling temperatures. Mechanical properties and microstructure depending on process speed.

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26 June / 09:20 - Room 15:

A modified carburizing heating pattern for enhancing the grain growth resistance of aluminum-killed steel bars

H. Jang
(China Steel Corporation, Taiwan)

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Title: A modified carburizing heating pattern for enhancing the grain growth resistance of aluminum-killed steel bars


Author:
H. Jang

Company:
China Steel Corporation, Taiwan

Co-Authors:
Y. Wang

Abstract:
Traditional carburizing parts such as gears and transmission shafts often have to be treated by a double quenching heat treating process in order to refine the grain size of steel matrix by the second quenching process with a relatively lower austenitizing temperature. However, the development of carburizing steels for advanced steel mills, precipitates controls have been used in the steel products to inhibit the abnormal grain growth or grain coarsening. Therefore, the second quenching process after carburizing can be omitted. That resulted in the effects upon reducing the cost and increasing the yield. In this research, the improved aluminum-killed steel bars produced by China Steel corporation are used for carburizing tests. The result shows that not only the grain growth can be inhibited subject to a high temperature carburizing treatment without a second quenching process, but the grain size of the carburizing work pieces will be further finer by forming a lot of finer AlN precipitates under a fine-tuned heating pattern of a carburizing process.

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26 June / 09:40 - Room 15:

Fine-grained low carbon bainitic steels with improved properties

H. Roelofs
(Swiss Steel AG, Switzerland)

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Title: Fine-grained low carbon bainitic steels with improved properties


Author:
H. Roelofs

Company:
Swiss Steel AG, Switzerland

Co-Authors:
R. Kuziak, R. Rozmus, L. Oberli

Abstract:
Reducing the weight of car components has led to more filigree parts and the use of stronger materials. Conventional solutions with quenched and tempered steels not always fulfil the wishes concerning technical reliability, economics and environmental friendliness. Continuously cooled bainitic steels are sometimes clearly better balancing these aspects which has led to a successful introduction into car components during the last decade. However, bainitic steels often do not reach the high Charpy impact toughness values of quenched and tempered steels. This is in particular true at sub-zero temperatures and after thermal or thermo-chemical treatments. Applying innovative technologies the above mentionned handicap can be reduced or completely elimated by refinement of the prior austenite grain sizes (not only in flat products but also in long products). In the present work the industrial production technology “XTP” was applied to produce fine-grained low carbon bainitic-martensitic steel bars. In comparison with conventionally hot rolled bars the Charpy transition temperature then was decrease by ~60°C. Charpy impact toughness values were shown to be stable during tempering treatments between 400 and 600°C. The influence of tempering on microstructure and mechanical characteristics were investigated in detail and will be discussed. Results demonstrate significant improvements in comparison with conventionally produced bars. The unique propertiy combinations found open new perspectives in challenging applications.

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26 June / 10:00 - Room 15:

Improvement of grain coarsening on the surface of low carbon wire rods after annealing

C. Lu
(China Steel Corporation, China)

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Title: Improvement of grain coarsening on the surface of low carbon wire rods after annealing


Author:
C. Lu

Company:
China Steel Corporation, China

Co-Authors:

Abstract:
Low carbon wire rod is widely used in manufacturing industry components such as rivets. Due to mechanical property and drawability, annealing heat treatment is inevitably applied to soften the material during the wiredrawing process. However, the annealing parameters such as heating time, temperature and rate depends on the process design and heating furnace. Under specific process, such as high annealing temperature or slow heating rate, the coarsen ferrite grain sometimes can be observed, which will result in orange peel defect on the surface of rivert. Therefore, the mechanism of the abnormal growth of ferrite grain after annealing is well investigated in this study. It’s shown that the as-rolled ferrite grain size and AlN precipitation behavior has a significant influence on the grain growth. Thus by making stock rolling in ɑ-phase and slow cooling rate after rolling, CSC develops the anti-coarsening low carbon wire rod, which can ensure the material with fine ferrite grain after annealing.

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26 June / 10:20 - Room 15:

Requirements for a digital twin for fatigue assessment with respect to the cyclic material behavior

R. Wagener
(Fraunhofer Institute for Structural Durability and System Reliability, Germany)

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Title: Requirements for a digital twin for fatigue assessment with respect to the cyclic material behavior


Author:
R. Wagener

Company:
Fraunhofer Institute for Structural Durability and System Reliability, Germany

Co-Authors:

Abstract:
A digital twin is a numerical model of the reality. In case of a digital twin for cyclically loaded safety relevant components of steel with respect to light-weight design multiple influences have to be considered in order to exploit the advantages of new material developments. Besides the influences of the loading boundary conditions, manufacturing parameters like the cooling route and local deformations affect the cyclic material behavior. However, due to the multiple influences and their interactions it is not possible to perform an experimental characterization of all parameters. Therefore, different estimation methods like Synthetic Wöhler-curves or Uniform Material Law in case of strain-life curves have been developed. Independent of the type of Wöhler-curve all these estimation methods are based upon databases which have been collected with different scopes of investigation. With respect to big data analyses a lot of database entries are not sufficient, because the documentation is not consistent. In order to develop a digital twin for the numerical fatigue approach the database must consider the main influences caused by the manufacturing process, the geometry and loading conditions. In order to build up a database, which enables big data analysis with respect to the local material behavior of modern steels, the influence of anisotropy caused by the forging process, heat treatment and local cooling routes as well as the interaction of constant and variable amplitude loading on the cyclic material behavior of new steel generations will be discussed. With respect to the setup of a digital twin, it is questionable, if the phenomenological size effects according to Kloos may be employed or if more sophisticated approaches are required. Furthermore, this discussion leads to the derivation of requirements for a material data space in order to improve the numerical fatigue approach considering the main influences of manufacturing and loading.

Steel materials and their application: High strength steels for bars and wire rods for automotive and engineering industry II (26 June / 11:20 - Room 15)

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26 June / 11:20 - Room 15:

Influence of cooling schedule on microstructural heterogeneity in bainitic steel wires

Ackermann
(RWTH Aachen University/Arcelor Mittal, Germany)

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Title: Influence of cooling schedule on microstructural heterogeneity in bainitic steel wires


Author:
Ackermann

Company:
RWTH Aachen University/Arcelor Mittal, Germany

Co-Authors:
B. Resiak, P. Buessler, S. Gremme, W. Bleck

Abstract:
In the field of long products, final parts often have to meet high demands on the mechanical properties to endure for example cyclic loading or high impact energies. A precise control of the cooling parameters produces a microstructure tailored to obtain specific properties. The investigated bainitic steels consist of bainitic ferrite as primary phase, Martensite-Austenite (M/A) constituent and retained austenite films, representing the secondary phase. Hot deformation trials with subsequent continuous cooling were carried out in a thermomechanical treatment simulator to produce a dominantly lower and upper bainitic microstructure in two different low alloyed carbon steels with different Molybdenum content. The cooling parameters were set according to the process window of the Stelmor cooling system for wire rod production. The microstructural analysis showed inhomogeneities in the appearance of the secondary phase depending on the cooling schedule. Some cooling cycles result in a more inhomogeneous microstructure, whereas certain cooling parameters were less sensitive to influence the final microstructure. A quantitative analysis of the microstructural constituents indicated that the scatter in size of the M/A constituents can be correlated with the mechanical properties. Therefore, the cooling cycle can be used to adjust the appearance of M/A constituents to achieve the desired mechanical properties.

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26 June / 11:40 - Room 15:

Development of high strength leaf spring steel

D. Kumar
(JSW Steel Ltd, India)

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Title: Development of high strength leaf spring steel


Author:
D. Kumar

Company:
JSW Steel Ltd, India

Co-Authors:
S. Kumar, K. Ragu, V. Singh, P. Tripathi

Abstract:
The suspension leaf spring is one of the most critical components of automobile which governs the riding quality. The steels used for manufacturing of these leaf springs are generally low-alloy manganese, medium-carbon or high-carbon steel with very high yield strength. These are made from continuously cast billets, rolled into flat shapes. The leaves are heat treated after the forming process to achieve the final strength. The yield strength of commonly used leaf spring grades such as SUP-11 grades is in the range of 1400 to 1450 MPa. The present work shows the development of new spring steel through offline simulation method with increased yield strength (> 1550 MPa).. The composition was C-M-Cr-Ni based, finalised using J-Mat Pro and rolling was simulated in Gleeble Thermo-mechanical simulator. The finalized composition was cast in an induction furnace and forged to break the cast structure. In the rolling mill, initial 5 passes are roughing passes whereas the subsequent passes 1-15 are the finishing passes wherein the deformation is provided in alternate passes in mutually perpendicular directions. The total reduction ratio was higher than the Gleeble limits, hence only passes which were below non -crystallization Temperature were simulated in Gleeble, keeping the strain and strain rates similar to the mill. It was found that the Gleeble simulated samples for the new alloy composition have substantially higher (~14%) hardness than that of SUP11A grade. The comparison of flow stress during the deformation, and final hardness and microstructure between the standard SUP11A and new composition indicated that the selected composition can be successfully utilized for the actual plant production of high strength spring steel. KEYWORDS : Thermo-mechanical simulation, Gleeble, grade development, leaf spring application.

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26 June / 12:00 - Room 15:

Development and application of thin gauge ultra fast cooling process wear-resistant steel

He
(Wuhan Branch of Baosteel Central Research Institute, China)

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Title: Development and application of thin gauge ultra fast cooling process wear-resistant steel


Author:
He

Company:
Wuhan Branch of Baosteel Central Research Institute, China

Co-Authors:

Abstract:
The production of thin gauge steel for construction machinery, especially high strength wear resistant steel, is limited because of the lack of heat treatment production line for sheet metal in WISCO. Under this background, it is necessary to develop the ultra fast cooling technology for high strength wear resistant steel by utilizing the 2250mm hot strip rolling line and its ultra fast cooling equipment of WISCO, which can cancel the offline quenching and tempering process for traditional wear resistant steel, so as to quickly seize the market with the advantages of high performance cost ratio. The stage achievement is illustrated in this paper. Based on the progressiveness of ultra fast cooling technology and the production dilemma of high strength wear resistant steel in WISCO, the thin gauge wear resistant steel has been successfully developed by reasonable composition design (CE is below 0.5%), smelting, continuous casting ,controlled rolling and controlled cooling especially ultra fast cooling process. The microstructure is fine and uniform lath martensite, and retained austenite (content 1%~2%). Retained austenite can effectively reduce the yield-strength ratio and obtain excellent workability, cold bending performance and low temperature toughness products. The properties are excellent, strength and toughness, hardness and cold bending performance reach even far beyond the technical requirement, fully meet the requirements of welding and processing in the downstream engineering machinery industry. For example, the hardness reaches 430~450HBW, the center hardness reaches 103% of the surface, while the longitudinal impact energy of -20℃ is above 37J (sample size: 7.5 ×10 ×55mm), the transverse cold bending property can bend beyond 120° without crack at the condition of diameter equaling 4 multiply by thickness. In conclude, the effect of water instead of alloy has been realized through ultra fast cooling process, the production cost is significantly reduced, and labor productivity is significantly improved.

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26 June / 12:20 - Room 15:

Use of self-learning technology software for high carbon steels

E. Martinez Rehlaender
(SvMet Engineering S.A., Mexico)

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Title: Use of self-learning technology software for high carbon steels


Author:
E. Martinez Rehlaender

Company:
SvMet Engineering S.A., Mexico

Co-Authors:

Abstract:
With an increasing demand for more accuracy in steel properties in the high carbon steel market [tire cord, bead cord, PC wire] it has become necessary to use highly advanced software tools. Namely the use of self-learning objects or quasi-AI. Zero deviation from mechanical properties "bands" such TS or reduction of area for assure-safety products has promoted the above mentioned technology. Accurate additions systems during steelmaking as well as sophisticated temperature adjusting systems {Castev} have been tested for several products. In this paper the results and observations of such technology is presented. Terms like SDT {suggested delivery temperature} are now being used for high carbon steel production as well as other products. Results of rod microstructure indicate that the methods used are accurate enough to achieve the required specs to ensure zero deviation. The above is the result of careful management of steelmaking process done with self-learning objects in software tools.

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26 June / 12:40 - Room 15:

Application of numerical simulation to predict microstructure and hardness of Q&T steel forgings

E. Anelli
(Franchini Acciai SpA, Italy)

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Title: Application of numerical simulation to predict microstructure and hardness of Q&T steel forgings


Author:
E. Anelli

Company:
Franchini Acciai SpA, Italy

Co-Authors:
A. Chugaeva, M. Lucchesi

Abstract:
Calculation tools to predict the thermal and microstructural evolution during quenching and tempering (Q&T) have been developed and applied. Activities carried out for the setup and tailoring of the coefficients of both heat transfer and phase transformation models are presented. In particular, cooling characteristics of stirred aqueous polymer quenchants were characterized by means of laboratory tests according to ASTM D 6482 and industrial trials using steel blocks instrumented with thermocouples. The commercial 3D FEM software DEFORM-HT able to calculate the thermal and microstructural evolution and the stress field during quenching was specialized for steels of interest and available quenching facilities. Moreover, an in-house 2D finite volume thermal-metallurgical model, specific for components of simple shape, such as bars, pipes, and blocks, has been developed, calibrated and applied. In both cases, the austenite transformation is determined by considering the cooling curve as a series of micro-isotherms and applying the laws governing the isothermal austenite transformation, derived by isothermal diagrams for diffusive transformations. Furthermore, martensite formation is calculated as a function of undercooling below martensite start temperature. The hardness of each phase is calculated after both quenching and Q&T from the chemical composition and the tempering conditions according to empirical regression formulas. The total hardness is calculated using a linear mixture law, using as weights the volume fractions of the microstructural constituents. The results of numerical modelling have been compared with actual properties of quenched and tempered forgings made of different steels. The microstructure has been investigated and hardness measured in order to verify the numerical model accuracy. The optimal design of the heat treatment in order to develop the target microstructure and strength levels and reduce the risk of quenching cracks are discussed with reference to forged components for power generation and oil & gas sectors.

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26 June / 13:00 - Room 15:

The research on the properties of 16MnCrS5 carburizing gear steel via continuous bloom casting

Z. Ding
(Baosteel special Metals long Product Co.,Ltd., China)

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Title: The research on the properties of 16MnCrS5 carburizing gear steel via continuous bloom casting


Author:
Z. Ding

Company:
Baosteel special Metals long Product Co.,Ltd., China

Co-Authors:
X. Meng

Abstract:
The research on 16MnCrS5carburizing gear steel by adpotion of the process of continuous bloom casting was analyzed in this article,compared with the traditional process via ingot casting,the bar yield was improved more than 10%,and the influences of the new process on the component homogeneity,microstructure and properties of steel were investigated.The research results indicated that produced via continuous bloom casting is equal to that produced via ingot casting in chemical component homogeneity,macro-structure, grain sizes,end hardenability ,mechanical property. At the meantime with the full protect casting for continuous bloom casting,the oxide inclusioncontent of continuscasting steel was lower than that of ingot casting steel .

Steel materials and their application: Solutions for hydrogen embrittlement of high strength steels (26 June / 14:20 - Room 15)

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26 June / 14:20 - Room 15:

Sensitivity of high-strength fine-grained steel to hydrogen under consideration of the welding process

M. Christ
(RWTH Aachen University, Germany)

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Title: Sensitivity of high-strength fine-grained steel to hydrogen under consideration of the welding process


Author:
M. Christ

Company:
RWTH Aachen University, Germany

Co-Authors:
Z. Sheng

Abstract:
Damages caused by so-called hydrogen induced cold cracking (HIC) are a widespread and feared phenomenon in connection with welding of metallic materials and occur in particular when there is a critical combination of hydrogen content in the welding zone, unfavourable stress state and susceptible microstructure. The hydrogen absorption into the welding zone is influenced, for example, by the selected welding process, the welding parameters, the condition and chemical composition of the materials (filler/ base metals, welding consumables), the workpiece geometry and the temperature cycle. The resulting microstructure in the weld zone, i.e. in the weld metal and in the heat-affected zone, determines the hydrogen transport by diffusion and effusion and influences the residual stress condition and ductility of the weld joint. Due to the material-specific microstructures and the resulting high strength of HSLA steels, these steels are considered to be particularly at risk. Depending on the hydrogen content in the material, property changes may occur with regard to the mechanical-technological properties. Investigations are carried out which deal with the fundamental sensitivity of high-strength structural steel S690QL to hydrogen and also consider the resulting influence on weldability. A major challenge in welding manufacturing is therefore to avoid a critical superposition of the influencing factors mentioned above. Within the framework of this work, gas metal arc welding (GMAW) is used as industrially relevant welding process in order to investigate indications of HIC during welding of high-strength structural steel S690QL.

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26 June / 14:40 - Room 15:

Resistance spot welding under external load for evaluation of LME susceptibility of zinc coated advanced high strength steel sheets

J. Frei
(Fraunhofer Institute for Production Systems and Design Technology, Germany)

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Title: Resistance spot welding under external load for evaluation of LME susceptibility of zinc coated advanced high strength steel sheets


Author:
J. Frei

Company:
Fraunhofer Institute for Production Systems and Design Technology, Germany

Co-Authors:
M. Rethmeier, M. Biegler

Abstract:
Some zinc coated advanced high strength steels (AHSS), under certain manufacturing conditions, are known to be prone to liquid metal embrittlement (LME) during resistance spot welding. LME is an undesired phenomenon, which can cause both surface and internal cracks in a spot weld, potentially influencing its strength. An effort is made to understand influencing factors of LME better, and evaluate geometry-material combinations regarding their LME susceptibility. Manufacturers benefit from such knowledge because it improves the processing security of the materials. The experimental procedure of welding under external load is performed with samples of multiple AHSS classes with strengths up to 1200 MPa, including dual phase, complex phase and TRIP steels. This way, externally applied tensile load values are determined, which cause liquid metal embrittlement in the samples to occur. In the future, finite element simulation of this procedure gives access to in-situ stress and strain values present during LME formation. The visualization improves the process understanding, while a quantification of local stresses and strains allows an assessment of specific welded geometries. The paper includes initial results from IGF research project no. 19311 N (FOSTA P1138)

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26 June / 15:00 - Room 15:

Detection method for liquid metal embrittlement cracks inside the intermediate sheet zone of dissimilar resistance spot welds

S. Lindner
(Outokumpu Nirosta GmbH, Germany)

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Title: Detection method for liquid metal embrittlement cracks inside the intermediate sheet zone of dissimilar resistance spot welds


Author:
S. Lindner

Company:
Outokumpu Nirosta GmbH, Germany

Co-Authors:
R. Deike

Abstract:
Liquid metal embrittlement (LME) is a phenomenon, which is described in literature by an intergranular crack path. A first systematic investigation about brittle grain boundary fracture was given by Roberts-Austen in 1888, but it was only since 1914 that “liquid metal embrittlement” was published as a specified topic by Huntington who investigated the damaging effect of liquid mercury in a solid copper-zinc-alloy. In the meantime, numerous investigations for different metal systems and applications are known in the literature, where a liquid metal damages a solid bulk metal. Notwithstanding the long time period, LME remains an actual as well as a still not understood topic. A so far not yet investigated area of the LME-phenomenon can be defined with ultra-high strength austenitic (stainless) steels for passenger cars. The mostly used joining procedure in car body engineering is still resistance spot welding. In this application, the uncoated surface of an austenitic steel is because of a lap joint configuration in direct contact with zinc-coated steels. During resistance spot welding liquid zinc penetrates inside the intermediate sheet zone the grain boundaries of the austenitic steel surface and is therefore able to initiate LME cracks. This results on the question of a process-reliable testing and detection method: Destructive testing methods must be probably excluded to avoid a further crack expansion. The paper will explain the way how to use and qualify a non-destructive testing method for the question of LME cracks. In a second step the crack characteristics are explained by radioscopic results. Further investigations about influencing parameters will be pointed out. The presented results will further complete the understanding of LME. In combination with the qualified non-destructive testing method, the results help to find a reliable and reproducible way for this steel problem inside car body manufacturing for the future.

Surface technologies (27 June / 09:00 - Room 6)

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27 June / 09:00 - Room 6:

Industrial applications of on line and real time microscopy

G. Moreas
(CRM Group, Belgium)

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Close27 June, Room 6 ( 09:00 )
Title: Industrial applications of on line and real time microscopy


Author:
G. Moreas

Company:
CRM Group, Belgium

Co-Authors:
O. Herbiet

Abstract:
The On Line Microscopy system (OLM), developed by CRM, has several applications in industry. Some of these will be detailed in this presentation. This measurement system has the following specifications: a field of view from 250µm to 5000µm with a precision down to less than 1µm, a software-controlled auto-focus, an acquisition rate up to several kHz depending on the camera, a light pulse down to a few nanoseconds and image processing dedicated to the various applications. Among the applications, one consists in the characterisation of the pickling state based on the shadowed zones put in evidence by dark-field illumination. A second application currently daily running concerns the characterisation of the galvannealed strip by the analysis of the type and the amount of crystals present at the surface of the product. A third application, nowadays sold worldwide at more than 60 exemplars, is used to measure the roughness of the strip surface especially for automotive applications. This has been recently upgraded with the measurement of the waviness also for automotive applications. Another application, under way, consists in the study of the grain size evolution on galvanised product in relation with the final quality of this product in term for example of zinc coating properties. The applications are not limited to the above mentioned ones. The last version is using LED illumination with very short pulse (200ns) leading to a system requiring less maintenance. This is also using an electrically tunable lens for the focus. The result is an industrial system with increased compactness and modularity for every kind of measurement based on surface characterisation at microscopic level.

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27 June / 09:20 - Room 6:

Towards measuring surface quality by means of automatic surface inspection systems

J. Brandenburger
(VDEh Betriebsforschungsinstitut GmbH, Germany)

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Title: Towards measuring surface quality by means of automatic surface inspection systems


Author:
J. Brandenburger

Company:
VDEh Betriebsforschungsinstitut GmbH, Germany

Co-Authors:

Abstract:
Even today, no one in the world can precisely quantify ASIS performance for the whole running production as in contrast to common measuring systems where the accuracy of the measurement is well defined, it is almost impossible for the user to determine comparable quantities for an ASIS. In the European RFCS project “CHECKSIS” methods were developed to enable the automatic verification of the ASIS performance. Results of the project were used to initiate the definition of a first official standard for ASIS in flat steel production that will be released as part of the well-established VDI/VDE/VDMA guideline 2632 for machine vision systems. This guideline should lead to comparable ASIS results of proven reliability as a first step towards real measurement of surface quality. The proposed methods are able to detect de-creasing ASIS performance, ensure long-term ASIS stability and reach documented reliability mandatory to turn ASIS into certified ASIS. This paper discusses the project results and the concepts developed for ASIS stability testing.

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27 June / 09:40 - Room 6:

Advanced technology for high quality and high productivity in hot dip continuous galvanizing line

H. Kakuno
(Nippon Steel & Sumikin Engineering Co., Ltd., Japan)

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Title: Advanced technology for high quality and high productivity in hot dip continuous galvanizing line


Author:
H. Kakuno

Company:
Nippon Steel & Sumikin Engineering Co., Ltd., Japan

Co-Authors:

Abstract:
Nippon Steel& Sumikin Engineering (hereinafter referred to as “NSENGI”) has supplied fivty-six(56) Hot Dip Continuous Galvanizing Lines (hereinafter referred to as “CGL”) for automotive and construction use all over the world. Recently, the request for high-quality and high-productivity of CGL is increasing. NSENGI has developed the advanced technology in order to accommodate the request focusing on surface quality of products and high-speed line operation. 1. Advanced Air knife system(NS blade® ) NSENGI has been developing the Air knife for Coating machine as the key technology of CGL. NS blade® was developed to prevent the zinc splash of strip edge and edge over coating which harmed the high speed and thin coating operation. After a pilot test in an experimental line, NS blade® was already applied in lots of customer at present. As a result of actual operations, NS blade® conduced to the following effect. ・Splash: High speed and thin coating weight operation (at operation speed 200mpm of 55%AL-Zn) ・Edge over coating: No edge over coating, off course flat winding ・Dross reduction: Blade effect can achieved dross reduction In consideration of industry 4.0, Remote maintenance and observation system is provided. 2. Advanced work roll cleaning system for Skinpass mill Skin pass mill work rolls have been used in order to improve the final strip quality such as mechanical property, strip flatness, and surface roughness in CGL. Before now, In-line cleaning device for work rolls of several type cleaning systems are applied. However, these systems are adequate in the complete removal of the solid sticking substance (e.g., zinc powders) from work rolls while maintaining its rough surface. NSENGI has developed the “Cavitating Jet in Air” cleaning system to realize the removal of the solid sticking substance with its roughness kept in the desirable condition. Moreover, NSENGI introduced “Cavitating Jet in Air” cleaning system into a CGL in commercial production and it has obtained fruitful results.

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27 June / 10:00 - Room 6:

Influence of surface profile on rust resistance of IF Steel during interval of working processes

B. Fang
(Baosteel-NSC Automotive Steel Sheets Co., Ltd., China)

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Title: Influence of surface profile on rust resistance of IF Steel during interval of working processes


Author:
B. Fang

Company:
Baosteel-NSC Automotive Steel Sheets Co., Ltd., China

Co-Authors:

Abstract:
During the manufacturing process of cold rolled auto sheet steel, a short transiting time are of demand between two processes, which is commonly about one to three days. In order to prevent the steel from rusting during these days, some measures have to be used, among which the residue rolling oil are the option in most cases. This paper is aimed to investigate the relationship among three-dimensional (3D) surface profiles, surface residues and corrosion rates of IF steel, further to explore the influence of surface morphology on the rust resistance during the interval of working processes. A white-light interferometry profilometer, scanning electrochemical polarization measurements and chemical analysis were used in this study. Results showed the residue oil is the key factor to affect the rust resistance of the sheet. Meanwhile, rolling oil is more likely to stay in the valleys. Therefore, a parameter of three dimensional surface profile, valley proportion, was the critical to determine the corrosion resistance of the sheet. It was found that sample AO presented the least proportion of valley, the least amount of residual oil, which promoted the penetration of corrosion media, and subsequently the worst rust resistance during the interval of working processes. This study will be of great help to improve the rust resistance of the auto steel by simply changing the valley proportion.

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27 June / 10:20 - Room 6:

Influence of Surface Roughness of Full Hard Steel on Spangle of Galvanized Steel Used in Exposed Galvanized Steel

T. Park
(Hyundai Steel Co., Ltd., South Korea)

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Title: Influence of Surface Roughness of Full Hard Steel on Spangle of Galvanized Steel Used in Exposed Galvanized Steel


Author:
T. Park

Company:
Hyundai Steel Co., Ltd., South Korea

Co-Authors:
S. Choi

Abstract:
According to rising demand of galvanized steel using automotive panel widely, Many studies related to surface quality improvement of galvanized steel have been done. In case of galvanized steel, Zn grain called as spangle is formed during solidification of Zn. It is known that surface quality properties of galvanized steel vary depending on spangle size. In this paper, we focus influence of surface roughness of Full hard steel by surface treatment condition on spangle size of galvanized steel. Difference in surface treatment condition leads to difference of surface area of full hard steel, which caused different spangle size.

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27 June / 10:40 - Room 6:

Numerical evaluation of surface roughness influences on cold formability of DP steel

P. Wechsuwanmanee
(RWTH Aachen University, Germany)

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Title: Numerical evaluation of surface roughness influences on cold formability of DP steel


Author:
P. Wechsuwanmanee

Company:
RWTH Aachen University, Germany

Co-Authors:
J. Lian, W. Liu

Abstract:
The microstructural configuration of DP steels with a soft ferritic matrix with embedded islands of hard martensite is the key feature to guarantee high strength, excellent ductility and cold formability, and high energy absorption in case of crash. However, due to this complex configuration, a variety of so far unknown damage initiation mechanisms has been activated, e.g. martensite-ferrite or ferrite-ferrite interface debonding or cracking of martensite. Depending on the subsequent damage accumulation, these mechanisms can result in critical macroscopic phenomena like fracture prior to necking in cold forming or pronounced edge crack sensitivity. Both phenomena are strongly influenced by surface roughness issues. The suggested contribution therefore presents an approach to explicitly consider surface roughness effects in a numerical simulation framework to predict the mechanical behaviour of DP steels. The approach is based on the coupling of damage mechanics modelling on the macroscopic scale and RVE simulations on the microscale. The latter ones geometrically consider roughness profiles that have been experimentally determined through surface investigations with confocal white light microscopy. The homogenization between the scales is achieved via weak macro-micro coupling in virtual experiments. The presentation will highlight some application examples where the suggested approach could serve to quantitatively assess roughness effects on cold formability of DP steels.

Additive manufacturing: Properties and quality of additive manufactured components II (27 June / 11:20 - Room 6)

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27 June / 11:20 - Room 6:

Innovative continuous process for AM metal powder production

M. Boccadoro
(Tenova S.p.A., Italy)

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Title: Innovative continuous process for AM metal powder production


Author:
M. Boccadoro

Company:
Tenova S.p.A., Italy

Co-Authors:
C. Cattalini, F. Memoli, W. Hopkins, K. Kemper

Abstract:
Tenova, a Techint group company, worldwide partner for innovative, reliable and sustainable solution in the metal and mining, and Phoenix Scientific Industries Ltd (PSI), well known provider from R&D to large scale production atomization systems and other solidification techniques, are developing together an innovative continuous process for metal powder production addressed to the Additive Manufacturing market. The aim of the paper is to illustrate a continuous processing route for AM metal powders production developed to maximize productivity rates, efficiency and flexibility while minimizing production costs and environmental impact. Together with other benefits, this processing system is designed to face the challenge of the industrialization phase relevant to AM Powder production processes.

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27 June / 11:40 - Room 6:

Production of high-grade metal powder for additive manufacturing by using the powder atomization plant of SMS group GmbH

T. Brune
(SMS group GmbH, Germany)

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Title: Production of high-grade metal powder for additive manufacturing by using the powder atomization plant of SMS group GmbH


Author:
T. Brune

Company:
SMS group GmbH, Germany

Co-Authors:
P. Weiland, M. Hüllen, J. Schlüter

Abstract:
In order to control and investigate all major steps of metal additive manufacturing, SMS group has set up a 3D Competence Center at their location in Moenchengladbach, Germany. A full scale powder atomization plant for the production of high-grade metal powders has been built to gain detailed operator know-how and production expertise to develop and produce different AM powders. A fully equipped laboratory guarantees high qualities for the further processing using a laser based powder bed fusion printer. The main goal is to analyze and develop the different influencing factors during atomization and further powder processing and the correlating properties during the downstream processing steps. By this full liner approach for the entire value chain of additive manufacturing, SMS can bring the best value to customers. In this paper, the Powder Atomization Plant and its technical features are described in detail to show the correlations of the powder processing and best results of the laser based powder bed fusion printer. To realize highest cleanness of the powder, the melting and refining of metals and alloys is taken place under vacuum or inert gas atmosphere. The atomizing process with argon or nitrogen, using the close-coupled principal, guarantees defined grain sizes and distribution of metal powders. An anti-satellite system is used for the needed spherical particles shapes which guarantee good flow properties during the 3D printing process. Combining a high utilization grade of metal powder and the right particle size and shape for additive manufacturing at highest quality, the new plant concept of SMS group demonstrates customers how to become the leading supplier of the AM industry.

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27 June / 12:00 - Room 6:

Automated tool-path generation for rapid manufacturing and numerical simulation of additive manufacturing LMD geometries

M. Biegler
(Fraunhofer Institute for Production Systems and Design Technology, Germany)

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Title: Automated tool-path generation for rapid manufacturing and numerical simulation of additive manufacturing LMD geometries


Author:
M. Biegler

Company:
Fraunhofer Institute for Production Systems and Design Technology, Germany

Co-Authors:
J. Wang, B. Graf, M. Rethmeier

Abstract:
In additive manufacturing (AM) Laser Metal Deposition (LMD), parts are built-up by welding layers of powder feedstock onto a substrate. Applications for steel powders include forging tools and structural components for various industries. For large parts, the choice of tool-paths influences the build-rate, the part performance and the distortions in a highly geometry-dependent manner. With weld-path lengths in the range of hundreds of meters, a reliable, automated tool path generation is essential for the usability of LMD processes. In this contribution, automated tool-path generation approaches are shown and their results are discussed for arbitrary geometries. The investigated path strategies range from classical approaches like “Zig-zag” and “contour-parallel-strategies” to more unusual solutions based on Hilbert-curves or the Travelling-Salesman problem. After generation, the tool-paths are automatically formatted into g-code for experimental build-up and ASCII for a numerical simulation model. Finally, the tool paths are discussed in regards to volume-fill, microstructure and porosity for the experimental samples and temperature flow for the numerical model. Guidelines are presented for the geometry-dependent selection of path-strategies. This work presents a part of the IGF project 18737N “Welding distortion simulation” (FOSTA P1140)

Additive manufacturing: Properties and quality of additive manufactured components I (27 June / 13:15 - Room 6)

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27 June / 13:15 - Room 6:

Physical and numerical modeling of close-coupled atomization processes for metal powder production

N. Vogl
(SMS group GmbH, Germany)

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Title: Physical and numerical modeling of close-coupled atomization processes for metal powder production


Author:
N. Vogl

Company:
SMS group GmbH, Germany

Co-Authors:

Abstract:
A full-scale pilot plant which uses the close-coupled atomization principle for metal powder production has been built up from SMS group. The properties of the final product depend on the uniformity of size and consistency of the powder. The particles are produced by close-coupled atomizers. An atomizer consists of a primary nozzle for the injection of liquid metal and a secondary coaxial nozzle for generation of a high speed gas jet. The secondary nozzle is designed as Laval nozzle resulting in supersonic flow conditions with complex shock and expansion wave pattern. The challenge lies in modeling of the mechanisms of liquid metal atomization under extreme process conditions. Better understanding of these phenomena is important for quality improvement, cost reduction and expansion of the product design pa-rameter space. The goal of this cooperative project is to develop a CFD model that calculates the particle size distribution for varying process parameters such as steel grade, superheating melt temperature, size of nozzles, gas-to-liquid ratio and others. In this paper, the pilot plant is introduced. In a laboratory setup for water atomization a model of the pilot plant has been built-up. In this model the operating conditions of the pilot plant are reproduced using the dimensional analysis of the scales influencing the atomization process. The setup allows to investigate the interaction between shock/expansion waves and water flow by Schlieren, PDA, and high speed measurements. Parallel to pilot-plant and experimental operation, the development of a CFD model for the atomization process has been started. The model shall be able to predict the behavior of the liquid fragments beneath the nozzles, the interaction between liquids and gas (shocks, ex-pansion waves) and lick-back phenomena. The status of this interdisciplinary project is de-scribed. Results from pilot-plant operation, laboratory tests and CFD simulations are discussed.

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27 June / 13:35 - Room 6:

Hot isostatic pressing (HIP) and main applications

A. Altay
(Saar Pulvermetall GmbH, Germany)

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Title: Hot isostatic pressing (HIP) and main applications


Author:
A. Altay

Company:
Saar Pulvermetall GmbH, Germany

Co-Authors:

Abstract:
Abstract: Hot isostatic pressing (HIP) is used for 2 main applications. Re-densification of casted, sintered and additive manufactured parts with pores to obtain a theoretical density of 100%. The 2nd area is the production of near-net shape components as composite or solid piece. It is filled into a steel capsule with powder and compacted under isostatic pressure and high temperature depending on the alloy. In composite parts, a solid shell or core serves as a carrier material to have a powder coating by diffusion bond connection with each other. As powder alloys are selected, which are not conventionally produced. Alloys with a high proportion of wear and corrosion-resistant components are melted and than gas atomized. This allows to obtain a uniform homogeneity of the atomized powder grains and to prevent segregation due to the high cooling rate. The subsequent shaping takes place by filling the powder in a sheet metal capsule. The filled capsule is evacuated and placed later into the HIP facility. Due to the isostatically applied argon gas pressure under the influence of temperature, the powder sinters. There is a solid-state diffusion at the grain boundaries and at the same time a 100% compaction of the pores. The homogeneity of the component is ensured by limiting a HIP temperature below Solidus. The subsequent processing can be carried out with conventional tools and machines or with other methods before and after a heat treatment. Examples of this technology can be listed as components for the extrusion machinery used for plastic market and the offshore industry. Other applications can be rollers, pressure vessels etc. with increased demands on the strength and wear and corrosion.

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27 June / 13:55 - Room 6:

Powder flow characterization for AM applications

F. Francqui
(Granutools, Belgium)

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Title: Powder flow characterization for AM applications


Author:
F. Francqui

Company:
Granutools, Belgium

Co-Authors:

Abstract:
Granular materials and metallic fine powders are widely used in many industry (3D Printing, sintering, alloys, …). To control and to optimize processing methods, the physics of powders must be precisely analysed. The measurement method based on the rotating drum can serve this purpose because the powder flow is analysed precisely (2.2%) at the powder / air interface without any compressive load. Moreover, it allows studying the relevant powders properties for AM: The Powders spreadability. Indeed, we have shown recently that the probability to obtain waves during the layer formation is proportional to the cohesive index measured by GranuDrum instrument. In addition to the flowability, the powder packing fraction is the other key parameter. Indeed, a high packing fraction reduces the porosity of the produced part. Therefore, a precise measurement of the range of packing fractions accessible by the powder is also necessary as precursors quality control. GranuPack instrument measures a compaction curve very precisely (0.4%). The bulk density, the optimal density, the compaction range and speed are extracted from this compaction curve. Moreover, the compaction curves of different samples can be compared to evidence differences regarding both density and flowability.

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27 June / 14:15 - Room 6:

Additive manufacturing at SMS group - a key technology for future production processes

T. Nerzak
(SMS group GmbH, Germany)

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Title: Additive manufacturing at SMS group - a key technology for future production processes


Author:
T. Nerzak

Company:
SMS group GmbH, Germany

Co-Authors:

Abstract:
METEC & 4th ESTAD 2019 Title Additive Manufacturing at SMS group – A key technology for future production processes Authors R. Banse, S. Hornickel, Th. Nerzak, A. Roßbach, N. Uppenkamp SMS group GmbH, Moenchengladbach, Germany Abstract Being a manufacturer of plants and machinery for the steel and NF-metals industry, SMS group’s objective is to provide integrated high-end turn-key solutions for our customers also in the field of Additive Manufacturing (AM). Following this path, we are equipped with a powerful 3D printer for a short time, which has been provided by our cooperation partner Additive Industries. The metal-powder bed printer will enable us to implement new production concepts in future. At the same time, it is a further step towards the integral AM approach by adding this laser beam melting machine to the full-scale pilot plant for metal powder production at our location in Moenchengladbach. The powder production plant as well as detailed backgrounds of the physical and numerical modelling of the respective atomization process will be presented separately. In laser beam melting processes, a high-purity homogeneous metal powder is melted by means of laser energy, layer by layer at defined positions. In this way, the component is gradually built up. By means of the powder bed technique it is possible to produce components of complex and unprecedented structures, which would not be feasible by conventional processes. The AM team at SMS group, which has been set up to advance and promote this innovative technology within the company, has already implemented a great number of innovative solutions for machine parts based on digital 3D design data, which impressively demonstrate the advantages Additive Manufacturing processes provide. Their most important benefits include significant weight reduction of dynamically actuated components, improvement of energy efficiency as a result of optimized flow patterns and minimized weight, simplification of mounting and adjusting procedures, easily customized design, dramatically shortened delivery periods and the possibility to produce locally. The paper and presentation will give a detailed look into a few typical AM design solutions that have already been implemented with success, thereby effectively contributing to significant increase in performance of our customer’s plants.