Purveyors of Processing Science and ICME: A SMD Symposium to Honor the Many Contributions of Taylan Altan, Wei Tsu Wu, Soo-Ik Oh, and Lee Semiatin: Modeling
Sponsored by: TMS Structural Materials Division, TMS: Shaping and Forming Committee, TMS: Titanium Committee
Program Organizers: Adam Pilchak, Pratt & Whitney; Ayman Salem, MRL Materials Resources LLC; Viola Acoff, University of Mississippi; Nathan Levkulich, UES; Michael Glavicic, Rolls-Royce; Yufeng Zheng, University of North Texas; John Joyce-Rotella, Air Force Research Laboratory
Tuesday 2:00 PM
February 25, 2020
Room: 30E
Location: San Diego Convention Ctr
Session Chair: Marko Knezevic, University of New Hampshire; Michael Glavicic, Rolls Royce
2:00 PM Invited
Genomic Materials Design: Science-based Engineering: Gregory Olson1; 1Northwestern University
Sixty years of academic collaboration and thirty years of commercialization by a network of small businesses have delivered a mature technology of computational materials design and accelerated qualification grounded in the CALPHAD system of fundamental databases now known as the Materials Genome. Two computationally designed aircraft landing gear steels have already been taken to full flight qualification employing this technology. The announcement in 2011 by the US President of a national Materials Genome Initiative acknowledging the reality of this technology has spurred global interest and rapid adoption by US apex corporations. Recent application has extended titanium alloy thermodynamic databases to incorporate atomic mobilities, molar volumes and martensite kinetic parameters, with application to castable and printable alloys extending basketweave microstructures to leaner compositions, as well as alloys demonstrating martensite reversion-enhanced recrystalization and TRIP Titanium alloys for porosity tolerance in printed components.
2:30 PM Invited
A Road Map of Four Decade Journey to Modeling Thermo-mechanical Processes and Microstructure Evolution: Ravi Shankar1; Wei-Tsu Wu1; BK Chun1; Jaebong Yang1; Jin Yong Oh1; Tim Hanes1; 1Scientific Forming Technologies Corporation
A brief review of four decade journey to modeling thermo-mechanical processes is a perfect way to acknowledge and thank the four stalwarts of their tremendous contribution to processing science and ICME. From there, this presentation delves into recent advances in various areas including meshing, handling multiple material groups, solvers, anisotropic modeling, DOE sensitivity analysis, optimization techniques and data analytics. These recent developments have helped to effectively model additive manufacturing, solid state welding and shot peening processes and few examples of these modeling applications will be presented. Enhancements to multi-scale microstructure modeling capabilities will be demonstrated. The impact of variabilities and uncertainties associated with processing conditions, boundary conditions and material properties on the evolution of microstructure during thermo-mechanical processing will be presented. Finally, a brief overview and application of data analytics tools to establish surrogate models will be demonstrated.
3:00 PM Invited
Application of the CALPHAD Method in the Framework of ICME: Fan Zhang1; Shuanglin Chen1; Weisheng Cao1; Chuan Zhang1; Duchao Lv1; Jun Zhu1; 1CompuTherm LLC
Phase diagrams are frequently referred to as roadmaps for alloy design and process optimization. Although initiated as a method of phase diagram calculation for complicated multicomponent systems, the CALPHAD approach has now been applied to various fields of materials science and engineering including solidification, coating, joining, and phase transformation. This has made the CALPHAD method a key building block of ICME. In this presentation, we will demonstrate that thermodynamic and phase diagram calculations can be integrated with kinetic models for the simulation of diffusion, precipitation, and solidification processes. These simulations can serve as virtual experiments for composition and process optimization, and provide valuable guidance for the design of real key experiments; therefore significantly reduce experimental work load and accelerate materials development. Application examples will be presented for variety of alloys, such as Al-based, Ti-based and Ni-based alloys. The advantages and limitations of the current CALPHAD tools will also be discussed.
3:30 PM
Development and Calibration of Numerical Meso-scale Models of Microstructure Evolution for Concurrent Recovery, Recrystallization, and Grain Growth with Zener Pinning: Eric Payton1; Austin Gerlt1; Matthew Krug1; Katelun Wertz1; 1Air Force Research Laboratory
From yield strength to creep resistance to fracture toughness, virtually every mechanical property of engineering alloys is affected by grain size. Microstructures retain a “memory” of prior processing history through the size, shape, orientation, and spatial distributions of phases and defects. A complex interplay exists between grain-size distribution shape, heterogeneity of stored strain, and joint size-spatial distributions of secondary phases. This is reflected in the time evolution of the grain-size distribution upon thermal exposure. We will present our efforts towards developing a fast-acting numerical meso-scale model of microstructure evolution that simultaneously incorporates the unified effects of recovery, recrystallization, grain growth, and secondary-phase pinning. The model synthesizes and builds upon seminal contributions to the field of metals processing science by Semiatin et al. Strengths and limitations of the approach with respect to enabling prediction of microstructure variation across forged components will be discussed, with emphasis on accurate measurement of input parameters.
3:50 PM Break
4:10 PM Invited
Integrated Approaches to Alloy Industrialization Using Numerical Simulation and Physical Modeling: Bruce Antolovich1; John Foltz1; Ramesh Minisandram1; John Mantione1; 1ATI Specialty Materials
Introduction of new materials for aerospace engine or airframe applications may take up to a decade. It is an expensive process; with compounding costs associated with each of the major steps including alloy design, sub scale evaluation, scale up activities and certification tests. By using both numerical and physical simulation, the time and cost required as well as the risk of failure during the later expansive stages of materials introduction are significantly reduced. Techniques of numerical simulation typically include thermodynamic modeling, deformation modeling and computational fluid dynamics. Physical modeling is performed using laboratory or industrial pilot scale equipment. The interactive combination of these two methods enables validation of theories at each stage of the development cycle, thereby optimizing efforts.Specific examples of accelerated development along with the tools by which they were developed will be shown for nickel base superalloys, titanium alloys and specialty steels.
4:40 PM
Hierarchical Multiscale Modeling of Microtextured Regions in Ti-6242 during Alpha/beta Processing: Timothy Truster1; 1University of Tennessee
Ti-6242 is a near alpha titanium alloy, which has excellent high-temperature creep resistance and is widely used in jet engine compressors. This alloy is susceptible to creep fatigue failure under dwell loading below 473 K. The existence of microtextured regions (MTRs) contributes significantly to this fast crack propagation. Previous investigations based on crystal plasticity finite element (CPFE) simulations have demonstrated the relationship between breakdown efficiency and loading direction during alpha + beta mechanical processing. In this talk, the behavior of MTRs with realistic initial microstructure is presented using a hierarchical multiscale modeling framework, and the microscale results are analyzed in detail to understand the behavior of MTRs under different loading conditions. It is shown that a hierarchical multiscale model with realistic initial microstructure at the microscale can reflect the influences from different strain paths, initial orientation distributions, and positions of the region simultaneously on the MTR breakdown efficiency.
5:00 PM
Modeling Beta Phase Texture Evolution during Alpha+Beta Forging to Understand Precursors to Coarse (“Abnormal”) Grain Formation: Adam Pilchak1; Austin Gerlt1; Eric Payton1; 1Air Force Research Laboratory
The evolution of beta phase deformation texture during alpha+beta forging has been identified as an important aspect of whether or not coarse or “abnormal” grains are formed. The effects of strain-path, strain-rate, and deformation temperature on the formation of the highly symmetric cube texture are explored using the viscoplastic self-consistent formulation. During heating through the alpha+beta phase field and above the beta transus, the cube texture grows preferentially compared to other BCC texture components. This phenomena is explored using a Monte Carlo model of grain growth augmented to include the effects of orientation-dependent stored work. The results are discussed in the context of production forging and strategies are offered to avoid coarse grain formation.