LAUSR

In this paper, a unified viscoplastic constitutive model for Ti–6Al–4V alloy coupling with damage and softening mechanisms was established to predict the flow behaviors and damage evolution in hot tensile process. To obtain the flow behaviors of Ti–6Al–4V alloy, the hot tensile tests were performed at temperatures between 750 °C and 850 °C and strain rates of 0.01–1 s−1. Then the evolution of microstructure was investigated by scanning electron microscope (SEM) under hot tensile conditions. Otherwise, the macro-fracture morphology of the tensile specimen was observed by SEM. The flow stress and microstructure evolution were predicted based on the set of constitutive model. The constitutive model was embed in ABAQUS by coding a user-defined material subroutine. The results show that the flow stress increases with the temperature decreasing and the strain rate increasing. By comparing the experimental and calculated results, the flow stress and damage evolution can be accurately predicted by the constitutive model. The fracture due to damage can be well predicted by the simulation model, indicating the good predictability of the constitutive model.