Finite Element Simulation of Micro Stresses and Micro Strains in Two-Phase Titanium Alloy during Tension

The microstructure of a two-phase Ti-6Al-4V alloy was obtained by scanning electron microscope, and then the finite element model of representative volume element (RVE) was established based on the microstructure by the combination of image processing and geometric modeling methods. The micro stresses and strains of RVE were simulated by the finite element software of ABAQUS and verified by the uniaxial tension test. The results show that the simulated stress-strain curve of RVE was in good agreement with the measured result, indicating the accuracy of the established RVE finite element model. Under the outer loads, the distributions of micro stresses and strains were inhomogeneous. The maximum stress existed in β phase while the maximum plastic strain occurred in α phase, and a relatively high fluctuation of the stresses and plastic strains occured near α/β interface. Plastic strain localization mainly occurred in α phase close to α/β interface and the following plastic strain failure band extended in α phase.