The damage mechanism of the metastable β-titanium alloy Ti5321 with specific microtexture using synchrotron X-ray microtomography

Abstract

In order to investigate damage mechanism of metastable β-titanium alloy Ti5321 with bimodal microstructure and specific microtexture, in situ tensile test was performed facilitating with synchrotron X-ray microtomography. The damage evolution of metastable β-titanium alloy Ti5321 can be predicted in three dimensions by proper micromechanics-based modelling methods, the Rice and Tracey model and Huang model. Through comparisons of the Rice and Tracey model and Huang model validated using the values of stress triaxiality calculated from experimental data and Finite Element (FE) simulations, the prediction accuracy of growth rates of voids can be enhanced. The results also show that the void growth is strongly related to microtexture of α plates. It is found that the growth path of largest voids is along α plates which have their c-axes with similar inclination angle of ∼45° from rolling direction (RD). Electron backscatter diffraction (EBSD) was also used to reveal the damage mechanism. This result is important enlightenment for study of damage mechanism of metastable β-titanium alloys.