Representative Volume Element Reconstruction and Crystal Plasticity ModelingStress-Strain Curves for Additively D. S. Bulgarevich1, M. Tsujii1, M. Demura2 and M. Watanabe1 Research Center for Structural Materials (RCSM), National Institute for Materials Science (NIMS) 2 Center for Basic Research on Materials (CBRM), National Institute for Materials Science (NIMS) We had succeeded to reconstruct the statistical representative volume elements (RVEs) of Hastelloy X samples manufactured at different conditions by laser powder bed fusion (LPBF) process. Due to the complex history of the laser heat gradients and scanning patterns, the accurate and realistic representation of geometrical and spatial characteristics of corresponding microstructure constituents in RVEs for stress-strain curve (SSC) predictions was a serious challenge. So far, the published works had dealt with less demanding material textures or relied on one-to-one or just visual correspondence (not statistical one) of RVE with experimental data. This work addressed such issues. It is demonstrated that experimental/simulated SSC correspondence can be predicted with our reconstructed RVEs by fine tuning of parameters in phenomenological model for crystal plasticity with an internal deformation resistance and a power-law relation between driving force and deformation rate. It is revealed that fitted SSCs correspond to liner isotropic slip hardening process in all Hastelloy X samples. Simulated well-fitted SSCs for different RVEs vary by just two kinematic hardening parameter values: by critical resolved shear stress for onset of plastic deformations and by initial increase in the yield strength of the material due to dislocation interactions. Caused by discontinuous columnar or/and grain microstructures in RVEs, there is very little anisotropy between simulated SSCs with loads along X-, Y-, and Z-axes which reflects the inconsistency of experimental results in this respect. 1 Design of High Temperature MParameter R. Sahara1 1 Research Center for Structural Materials, National Institute for Materials Science (NIMS) 72PP44--0077 PP44--0088 Most of conventional computer simulation techniques for designing high temperature materials introduce experimental data and empirical parameters. While, first-principles calculations based on density functional theory (DFT) is accurate but limited in their ability to characterize materials because of the very small time and spacial scales. The purpose of the research is to renew conventional numerical simulation techniques which relied on experimental data and empirical parameters and to apply advanced computer simulation techniques, by combining first-principles calculations and our own coarse-grained calculation techniques to provide theoretical guideline to design wide range of high temperature materials. Poster Presentation ｜NIMS Award Symposium 2023aterials Using a MManufactured Hastelloy X ultiscale Simulation without Empirical P4 ｜ Modeling of
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