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Title: Numerical modeling of Ti-6Al-4V microstructure evolution for thermomechanical process control
Microstructure evolution modeling using finite element crystal plasticity (FECP), Monte- Carlo (MC), and phase field (PF) methods are being used to simulate microstructure evolution in Ti-6Al-4V under thermomechanical loading conditions. FECP is used to simulate deformation induced evolution of the microstructure and compute heterogeneous stored energy providing additional source of energy to MC and PF models. The MC grain growth model, calibrated using literature and experimental data, is used to simulate α+𝛽 grain growth. A multi-phase field, augmented with crystallographic symmetry and orientation relationship between α-𝛽, is employed to model simultaneous evolution and growth of all twelve α-variants in 3D. The influence of transformation and coherency strain energy on α-variant selection is studied by coupling the model with the Khachaturyan-Shatalov formalism for elastic strain calculation. This FECP/MC/PF suite will be able to simulate evolution of grains in the microstructure and within individual 𝛽- grains during typical thermomechanical processing conditions.
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Proceedings of NUMIFORM 2019: The 13th International Conference on Numerical Methods in Industrial Forming Processes
Sponsoring Org:
National Science Foundation
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