Computational Techniques for Multi-Scale Modeling in Advanced Manufacturing: Multiscale Solid-state Models
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS Extraction and Processing Division, TMS: Computational Materials Science and Engineering Committee, TMS: Process Technology and Modeling Committee
Program Organizers: Adrian Sabau, Oak Ridge National Laboratory; Anthony Rollett, Carnegie Mellon University; Laurentiu Nastac, University of Alabama; Mei Li, Ford Motor Company; Alexandra Anderson, Gopher Resource; Srujan Rokkam, Advanced Cooling Technologies, Inc.
Thursday 2:00 PM
March 18, 2021
Room: RM 1
Location: TMS2021 Virtual
Session Chair: Srujan Rokkam, Advanced Cooling Technologies Inc.
2:00 PM Invited
Multiscale Crystal Plasticity in Integrated Computational Materials Engineering: Deepankar Pal1; Javed Akram1; Thaddeus Song1; Jobie Gerken1; Dave Conover1; 1Ansys
Micron scale structures or microstructures have become strongly coupled with their macroscopic counterparts in determining the bottom-up and top-down multiscale structural behavior with the advent of advanced manufacturing technologies such as additive manufacturing and castforging due to the spatiotemporal scales at which their fabrication driving forces operate. This coupling necessitates solving the single grain length scale problem with aspects of slip and twin systems appropriately captured to effectively simulate the steady state and transient behavior respectively. Although due to the spatiotemporal discretization, it is impossible to simulate large polycrystalline or subsequently the part scale structural behavior, thereby establishing the requirement for an Integrated Computational Homogenized Multiscale Structural approach. In response to this requirement, a generalized formulation with scale coupling coefficients effectively capturing the spatiotemporal characteristic dimension along with the distribution of physical and numerically computed mechanical properties such as the elastic and tangent moduli will be discussed during this talk.
2:40 PM
Microstructure Based Modeling of Friction Stir Welded Joint between Dissimilar Metals Using Crystal Plasticity: Shank Kulkarni1; Kyoo Sil Choi1; Piyush Upadhyay1; Ayoub Soulami1; 1Pacific Northwest National Laboratory
Many applications in the aerospace and automotive industry demand the use of lightweight materials such as magnesium alloys to reduce weight and increase fuel efficiency. Still, in some critical sections, the use of much stronger materials such as steel is inevitable. Due to the large difference in melting points of steel and magnesium alloy along with their immiscibility in the liquid state, makes it impossible to join them using traditional welding techniques. Friction stir welding shows promising results in joining these dissimilar metals. Being a new technique, the failure mechanism of the joint needs to be investigated. In this work, a joint between AZ31 and DP590 steel is modeled using phenomenological crystal plasticity formulation on mesoscale. The interface of the two materials is modeled using cohesive elements. A parametric study has been performed to understand the effect of grain size and interface strength on the mechanical performance of the joint.
3:05 PM
Modeling Material Behavior during Continuous Bending Under Tension for Inferring the Post-necking Strain Hardening Response of Ductile Sheet Metals: Application to Dual-phase Steels: Marko Knezevic1; Russell Marki1; 1University of New Hampshire
Continuous bending under tension (CBT) can stretch ductile sheet metals significantly more than simple tension (ST). Strength and plastic strain levels increase with the number of CBT cycles and substantially exceed those achieved in ST. Taking advantages of the improved elongation-to-fracture achieved by CBT, samples of dual-phase (DP) 590, 780, 980, and 1180 steels are pre-deformed to several strain levels by interrupting their CBT testing. Sub-size specimens are machined from the CBT interrupted specimens and tested in ST. The flow curves from these secondary ST tests are then shifted according to the axial strain accumulated during pre-deformation by CBT to determine large strain (post-necking) flow curve of the materials. The identified large strain flow curves are validated by simulate the load versus displacement curves during CBT and the flow curves based on the secondary ST testing using appropriate constitutive laws in finite elements demonstrating the utility of the developed methodology.
3:30 PM
Modeling the Role of Local Crystallographic Correlations in Microstructures of Ti-6Al-4V Using a Lamellar Visco-plastic Self-consistent Polycrystal Plasticity Formulation: Iftekhar Riyad1; Ricardo Lebensohn2; Brandon McWilliams3; Adam Pilchak4; Marko Knezevic1; 1University of New Hampshire; 2Los Alamos National Laboratory; 3CCDC Army Research Laboratory; 4Air Force Research Laboratory
This paper presents a multi-level crystal plasticity-based simulation framework for modeling mechanical response and microstructure evolution of Ti-6Al-4V. The model is a visco-plastic self-consistent (VPSC) formulation with an adaptation to linking three scales: a single crystals micro-scale, a lamellar colony meso-scale, and a lamellar aggregate macro-scale for lamellar microstructures. A hardening law in the model adjusts the resistances of basal and prismatic slip systems based on the geometry of possible slip transfer between adjacent lamellae. Consistent with experimental evidences, the resolved shear stress on the pyramidal slip planes considers the non-Schmid effects. Electron backscatter diffraction data in conjunction with a procedure relying on α→β phase transformation is used to construct paired variants of α-lamellae satisfying their local crystallographic correlations. The simulation framework is applied to interpret the deformation behavior of Ti-6Al-4V fabricated via laser powder bed fusion in stress-relived (SR) (α-lamellar structure) and heat treated ((α +𝛽)-globular structure) conditions.