Crystal Plasticity Based Finite Element Modeling in Polycrystalline Ti-7Al Alloys

Crystal Plasticity;Finite Element Method;Titanium alloys;Mechanical Engineering

Tao, Chengcheng

Johns Hopkins University

关键词: Crystal Plasticity;    Finite Element Method;    Titanium alloys;    Mechanical Engineering;   

Others  :  https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/37116/TAO-THESIS-2014.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: JOHNS HOPKINS DSpace Repository

【 摘 要 】

This thesis develops an experimentally calibrated computational model based on crystal plasticity for the analysis of α-Ti-7Al polycrystalline alloys. The crystal plasticity finite element model uses rate and size-dependent anisotropic elasto plasticity constitutive law. The study contains a combination of orientation imaging microscopy (OIM), misorientation, microtesting, computational simulations and minimization process, including genetic algorithms for calibration of the material parameters and characterization. Size effects are also taken into consideration in the analysis. The polycrystalline Ti-7Al computational model involves statistically equivalent orientation distributions to those observed in the orientation imaging scans. Simulations detected effects of orientation, misorientation and microtexture distributions through simulations. Constant strain rate test is simulated with this model, and the results are compared with experiments.