Academy Plenary Lectures

 
Prof. Frédéric Barlat
Pohang University of Science and Technology, Korea

Prof. Barlat is currently a professor at the Pohang University of Science and Technology (POSTECH) in the Republic of Korea. His research focuses on the development of innovative plasticity theories for metals as well as manufacturing technologies for steel products. He received a PhD in Mechanics from the Grenoble Institute of Technology, France, in 1984.  The same year, he joined Alcoa Technical Center near Pittsburgh PA, the research facility of Alcoa Inc, where he conducted scientific research for more than 20 years. Prof. Barlat has published over 250 peer-reviewed scientific articles and about 200 conference papers. He holds three US patents.
In 1995, he was the recipient of the ASM Henry Marion Howe Medal of the Material Society for the best technical paper published in Metallurgical Transactions A. He received the 2006 International Journal of Plasticity Award for Outstanding Contributions to the Field of Plasticity. In 2011, Prof. Barlat received the Lee Hsun Lecture Award from the Chinese Academy of Science. In 2013, he won the Khan International Award for outstanding life-long contributions to the field of Plasticity. Subsequently, a special issue of the International Journal of Plasticity was edited in his honor in 2015.  In 2016, he was elected by the Romanian Academy as an honorary member.

Title: Advanced Constitutive Modeling and Application in Sheet Forming

Abstract: Continuum constitutive descriptions of plasticity suitable for finite element simulations of sheet forming processes are succinctly discussed in this presentation.  Although multi-scale approaches allow for a more explicit representation of the physical deformation mechanisms occurring at microscopic scales, they are usually not suitable for industrial applications because of the quick turnaround time needed for process design simulations.  Therefore, advances in classical concepts such as plastic anisotropy and strain hardening are still very much in demand.  Actual forming simulation examples conducted for advanced high strength steels are presented for illustration purposes.


Dr. Yasumasa Chino
National Institute of Advanced Industrial Science and Technology, Japan

Dr. Yasumasa Chino is a group leader at Structural Materials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya, Japan. He received the degree of BS (1995), MS (1997) and Ph. D degree (1999) in Department of Materials Processing Engineering of Nagoya University, Japan. After a brief post-doctoral position in his PhD adviser’s group, he joined the AIST, and became a researcher (2000), senior researcher (2008) and group leader (2009).
His personal research interest is in the field of microstructure and texture control of magnesium alloys. Especially, his research is focused on texture control of magnesium alloys sheets for realizing press forming of magnesium alloy sheets at room temperature. In addition, now, he participates to national project “Innovative Structural Materials Project: NEDO Project, Japan”, where his research is focused on an enhancement of mechanical properties and productivity of flame retardant magnesium alloy (Mg-Al-Ca alloy) extrusions for realizing an application of its alloys to automobile body.

Title: Enhanced Room Temperature Formability of Magnesium Alloy Sheets by Suppression of Basal Texture Formation

Abstract: Magnesium (Mg) alloys are suitable materials for weight reduction in vehicles because of their low densities and high specific strengths. However, rolled Mg alloy sheets generally exhibit a poor formability at room temperature and thus their applications are restricted. This poor formability is originated from basal slip dominated deformation as well as strong basal texture. It is known that the formability can be improved by suppression of basal texture formation. Thus, large efforts have been devoted to texture control for the purpose of enhancing the room temperature formability. In this presentation, recent researches for texture control of rolled Mg alloy sheets are reviewed. Especially, enhanced room temperature formability of commercial Mg alloy (AZ31 alloy) processed by high-temperature rolling, where sheets are rolled at just below solidus temperature, are focused.


Prof. Viggo Tvergaard
Technical University of Denmark, Denmark

Prof. Tvergaard is a Professor Emer. of Solid Mechanics at the Technical University of Denmark. He got his Ph.D. in 1971 from the Technical University of Denmark, and his dr. techn. degree in 1978.
His primary research interests are instabilities of structures and solids, the mechanics of materials, fracture mechanics, damage mechanics, and micromechanics. Post-buckling behavior of structures, and tensile instabilities at large plastic strains have been studied. Also the micromechanics of damage has had much focus, including ductile fracture models, the micromechanics of intergranular creep damage, metal- ceramic systems, cohesive zone representations, and the mechanics of polymers.
Since 1995 he is the Editor-in-Chief of the European Journal of Mechanics A/Solids. He is a foreign member of Royal Netherlands Academy of Arts and Sciences, and of the US National Academy of Engineering, and is an honorary member of ESIS, Eur. Struct. Integrity Soc. He was appointed Visiting Professor of Engineering at Brown University 1989-94, obtained an Honorary Doctor Degree from the Royal Institute of Technology, Stockholm, Sweden, 1993, received the 1998 Koiter Medal of ASME, and the 2009 Euromech Solid Mechanics Prize. He has been selected for the 2017 Timoshenko Medal of ASME. Has published more than 330 international scientific articles. President of IUTAM from 2012 to 2016, now Vice-President of IUTAM.

Title: Plastic Flow Localization and Ductile Fracture

Abstract: Basic theory for bifurcation in elastic-plastic solids will be mentioned, leading to discussion of imperfection-sensitivity. Special interest will be devoted to localization of plastic flow, either as shear bands or as necking in thin sheets. In particular bifurcation into shear bands brings out the very strong sensitivity to the material model applied. Shear bands at realistic strains are not predicted by J2 flow theory with hardening, but this is changed by accounting for a vertex on the yield surface, by using crystal plasticity, or by accounting for the presence of porosity in the material. The effect of micro-voids is special at low hydrostatic tension, where the voids tend to be flattened out to micro-cracks, which then interact with neighbouring cracks. For a periodic array of voids this will involve shear band localization. Differences between a state of simple shear and a state of pure shear will be discussed.


Prof. Peidong Wu
McMaster University, Canada

Prof. Peidong Wu is Professor in the Department of Mechanical Engineering, McMaster University, Canada. He got his B.Sc., M.Sc. and Ph.D. from Zhejiang University, China University of Mining and Technology, and Delft University of Technology, respectively. In 1994, he was awarded the prestigious Canada International Fellowship by NSERC to conduct research work at the University of Sherbrooke. In 1997, he joined Alcan International Limited, Research & Development Centre, where he became a Technical Leader in 2001. Dr. Wu joined McMaster University in 2006.
Since 1982, Dr. Wu has been working in the field of the mechanics of engineering materials and composites, especially in the constitutive modeling of large deformation of polymeric materials and polycrystalline metals. Together with Professor Erik van der Giessen, they developed a non-Gaussian full network model for rubber elasticity. At Sherbrooke and Alcan, Dr. Wu’s research focused on sheet metal forming, including formability, bendability and roping of aluminum sheets. At McMaster, Dr. Wu and his students developed a finite strain Elastic-Viscoplastic Self-Consistent (EVPSC) model for polycrystalline materials, and a new Twinning and De-Twinning (TDT) model for HCP materials including magnesium alloys. In 2009, he was awarded the International Journal of Plasticity Medal for excellent contributions to the field of plasticity, especially to the areas of constitutive modeling and metal forming. In 2011, he received the NSERC Discovery Acceleration Supplement.

Title: Crystal Plasticity Modelling of Large Strain Behaviour of HCP Materials

Abstract: In this lecture, we first introduce various polycrystal plasticity models including the Visco-Plastic Self-Consistent (VPSC) model, the Elastic-Plastic Self-Consistent (EPSC) model, and the Elastic Visco-Plastic Self-Consistent (EVPSC) model, as well as twinning models including the Predominant Twin Reorientation (PTR) model and the Twinning and De-Twinning (TDT) model, with emphasizing on characteristic differences between these models.  Then, we demonstrate that the EVPSC-TDT model is able to capture key features of large strain behaviour of HCP materials (such as Mg, Ti and Zr alloys) under various deformation processes including uniaxial tension and compression, plane strain compression, simple shear, and torsion.

Industrial Plenar Lectures


 

Dr. Bart Carleer
AutoForm Engineering

Dr. Bart Carleer, born in 1969, has been the Corporate Technical Director of AutoForm since 2008. He holds a Ph.D. in Mechanical Engineering and, within the context of his dissertation, focused on the application of forming simulation for deep drawing. Before coming to AutoForm in 2003, he worked at steel and aluminum manufacturer Corus for over five years, with his last position as department head for sheet metal and hydroforming at Corus Research, Development and Technology. At AutoForm, he is responsible for the technical supervision of AutoForm products as well as training, support and technical product management.

Title:
Effective Stamping Simulations along the Sheet Metal Process Chain

Abstract:
Simulation is an inevitable technology in the development of stamping dies. The stamping technology evolves, part performance and quality requirements increase as well as processed materials change. So, stamping simulation tools must constantly be enhanced to follow these trends. Important topics in the industrial use are accuracy and speed; relevant in this matter are: • an effective engineering workflow with maximum flexibility in the early phase and high accuracy in the final phase, • proper representation of the physical process with precise tool definition, • accurate results for feasibility and springback to optimize the forming process and process parameters, • process capability and process robustness to strive for zero-defect tool- and part-production. The paper in hand will illustrate the above mentioned issues integrated in an effective engineering process of an automotive stamping part. High quality targets can consistently be achieved when following the proposed workflow.;

   
Dr. Hiroshi Fukiharu
JSOL CORPORATION

Dr. Hiroshi Fukiharu is Engineering Section Manager of JSOL Corporation. He is currently responsible for ‘JSTAMP’ which is one of the major sheet metal forming simulation software in Japan. The current development challenges are to advance the material modeling technique and to improve the implicit method for the complicated practical model, targeting to obtain more accurate results within short calculation time. He had contributed to the technological improvement during the time he had worked for NISSAN motor as a stamping engineer in stamping division, before he joined JSOL six years ago. He received Ph.D. at the University of Electro-Communications on the application of the improved multi-grid method for the elasto-plastic finite element analysis. He has participated in the Numisheet Benchmark multiple times.

Title:
The Current Status and Development of Practical Sheet Metal Forming Simulation

Abstract: In Sheet metal forming simulation is widely used for predicting formability and springback behavior of stamping parts. The increasing usage of low formability material such as high-strength steel and aluminum alloy has grown the importance of CAE technologies. JSOL responds to the expanding demand for CAE by developing and providing software JSTAMP (LS-DYNA). This presentation reports the current and development statuses of the practical use of CAE technologies. The current status is described by taking the springback simulation results as the example. The accuracy and the simulation time of springback prediction and springback compensation of the tool is presented. For the development effort, this presentation mentions the result obtained from different yield function to accomplish more accurate simulation, and the approach to optimizing CAE for hot forming. The technical development addressing the application of CAE for CFRP which are expected to become more common material for automobile part is also introduced.

   
Mr. Shinichiro Ohsawa
Toyota Motor Corporation

Mr. Shinichiro Ohsawa is Department General Manager at Toyota Motor Corporation Mid-Size Company in Stamping Engineering Division. Ohsawa oversees a group of 73 members with responsibility for CAE development, stamping design standards, and stamping die design. His team designs nearly 400 dies per year for new model deployment across Toyota's vast manufacturing operation while supporting mass production issues around the globe. His background within Toyota is mainly in the stamping field, starting as a die designer, moving on to plant production engineer and project management in both Japan and the US.

Title: Recent Applications and the Future Direction of Stamping Simulation in Toyota Motor Co.

Abstract: In the early days when CAE simulation was first introduced in stamping, it was limited to simulating sheet metal forming, such as evaluation of splits and wrinkles. Through the years, with the advances of simulation technology, we have been able to apply this technology to simulate dimensional accuracy, surface quality, panel rigidity, and cover a wide area of the stamping engineering field. Recently, the pursuit of making lightweight vehicles has required new materials, aluminum, UHSS, hot stamp steels. We have been developing the simulation technology to handle these new materials and using them in our new model projects. In the presentation, we would like to share how we have been applying stamping simulation at Toyota, and the development activities we have been doing, with our thinking of how we plan to move forward into the future.


   
Dr. Shunji Hiwatashi
Nippon Steel & Sumitomo Metal Corporation

Dr. Hiwatashi is the General Manager of Application Technology R&D Laboratory, Nippon Steel & Sumitomo Metal Corporation. He got his Ph.D. in 1998 from the Katholieke Universiteit Leuven, Belgium. He is now in charge of the R&D for the applications of advanced steel sheets and tubes to automotive bodies and chassis. His field of interests, thus, covers from the microstructures and mechanical behaviors of steels to the manufacturing technology and performance of automotive parts.

Title:
Simulation-aided Application of Advanced Sheet Steels to Automotive Parts

Abstract:
As a sheet steel supplier, we have developed practical technologies which improve the reliability of sheet forming simulations from the viewpoint of material behavior such as flow-stress evolution and fracture. These technologies contribute, not only to the efficient extension of steel applications, but also to the development of new forming technologies of advanced products with the latest steels. In the presentation, we will provide some examples of material models and parameter identification methods for the simulations of cold forming, as well as of hot stamping in which the consideration of phase transformation is needed. Furthermore, some prototyping activities will be presented as the latest applications of these technologies.;

   
Dr. Eiji Iizuka
JFE Steel Corporation

Dr. Eiji Iizuka is a senior researcher of JFE Steel Corporation. He joined JFE Steel Corporation in 1991. He have been involved in development of forming technology related to automotive parts. He is now work for NAGOYA branch office of JFE Steel Corporation.

Title:
Forming Analysis Technologies for Application of High Strength Steels to Automotive Parts

Abstract: There are many problems known such as cracks, wrinkles, surface defects, spring back, and galling in the application of high strength steel sheets to automotive parts. Stretch flange crack prediction, spring back prediction, and counter actions against the problems by FEM forming analysis are major concerns of the automotive engineers. The techniques of the stretch flange crack prediction and anti-spring back actions developed by JFE Steel Corporation will be presented in this lecture.

Industrial Keynote Lectures


   
Mr. Mototeru Oba
ITOCHU Techno-Solutions Co.

After finishing his master in mechanical engineering, Mr. Oba started his career at a bearing company and studied dynamic simulation of rolling bearings including advanced lubrication theories. Then he switched jobs to the current company. After focusing on the simulation of multibody dynamics for several years, he is now in charge of consulting Abaqus analyses as SIMULIA Technical Support Specialist. In parallel, he belongs to a cross-sectional research team on ICME, multiscale approach to extract metal properties from their microstructures. Besides the study on ICME framework, he has studied a consistency of an anisotropy in homogenization method.

Title:
Microstructure-Based Multiscale Approach to Obtain Mechanical Property of Duplex Stainless Steel According to ICME Concept

Abstract: We have proposed microstructure-based multiscale simulation framework based on Integrated Computational Material Engineering (ICME) concept and the framework was applied to the simulation of hot rolling process of duplex stainless steel. In the study, the hot rolling simulation was performed by Abaqus. The simulation was typical hot rolling simulation, except the mechanical property of slab. The property was calculated by homogenization method software HOMAT from its microstructure, which was simulated by MICRESS, microscale multi-phase field method simulation software. An elastic property of each phase in microstructure was obtained by nanoscale molecular dynamics simulation software LAMMPS and first-principles calculation software VASP. The simulation framework is introduced in this presentation.

   
Dr. Subir Roy
Altair Engineering, Inc.

Dr. Subir Roy has been working in manufacturing process simulation for the last thirty years. Currently, as Senior Technical Director of Manufacturing Solutions, Dr. Roy is responsible for the scope, user experience and development priorities of manufacturing process simulation software for stamping, casting, injection molding, extrusion, forging and additive manufacturing. Dr. Roy has published numerous technical papers in refereed journals and chaired technical sessions at highly regarded international forums. During his Ph.D. at the Ohio State University, Dr. Roy developed a unique methodology for optimization of multi-stage metal forming processes by coupling non-linear finite element analysis with Genetic Algorithms.;

Title:
Recent Developments in Multi-disciplinary Applications of Stamping Simulation

Abstract: Traditionally stamping simulation has focused on assessment of manufacturability at early product design phase and for process validation at the downstream phase. In the recent years, there has been an increasing trend towards expanding the scope of stamping simulation to integrate with other CAE domains such as structural CAE, composite materials, fatigue, safety, optimization, CFD, casting and lately 3D printing. The enablers are, highly streamlined graphical user interfaces for modeling and visualization combined with accurate, robust and scalable multi-physics solvers. In this talk, industrial case studies are presented on topography optimization and initialization of sheet metal parts with manufacturing results to improve structural stiffness, process optimization of complex stampings via highly scalable and accurate explicit analyses, topology optimization and manufacturability of stamping die structures, and thermo-forming of composite materials.