A High-Rate, Single-Crystal Model including Phase Transformations, Plastic Slip, and Twinning

Addessio, Francis L.¹  Bronkhorst, Curt Allan¹  Bolme, Cynthia Anne²  Brown, Donald William³  Cerreta, Ellen Kathleen³  Lebensohn, Ricardo A.³  Lookman, Turab¹  Luscher, Darby Jon¹  Mayeur, Jason Rhea¹  Morrow, Benjamin M.³  Rigg, Paulo A.⁴ 

[1] Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division;Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Explosive Science and Shock Physics Division;Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology Division;Washington State Univ., Pullman, WA (United States). Dept. of Physics. Inst. for Shock Physics

关键词: Titanium;    High-Strain Rate;    Crystal Plasticity;    Twinning;    Phase Transformations;   

DOI  :  10.2172/1312644
RP-ID  :  LA-UR--16-26524
PID  :  OSTI ID: 1312644

学科分类：材料科学（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

An anisotropic, rate-??dependent, single-??crystal approach for modeling materials under the conditions of high strain rates and pressures is provided. The model includes the effects of large deformations, nonlinear elasticity, phase transformations, and plastic slip and twinning. It is envisioned that the model may be used to examine these coupled effects on the local deformation of materials that are subjected to ballistic impact or explosive loading. The model is formulated using a multiplicative decomposition of the deformation gradient. A plate impact experiment on a multi-??crystal sample of titanium was conducted. The particle velocities at the back surface of three crystal orientations relative to the direction of impact were measured. Molecular dynamics simulations were conducted to investigate the details of the high-??rate deformation and pursue issues related to the phase transformation for titanium. Simulations using the single crystal model were conducted and compared to the high-??rate experimental data for the impact loaded single crystals. The model was found to capture the features of the experiments.