A crystal plasticity-based constitutive model for near-β titanium alloys under extreme loading conditions: Application to the Ti17 alloy

Abstract

A crystal plasticity-based constitutive model is proposed to describe the thermo-mechanical behavior of the Ti17 titanium alloy subjected to extreme loading conditions. The model explicitly incorporates the effect of the crystallographic orientation of the hcp and bcc phases. The constitutive equations are built in the context of continuum thermodynamics with internal variables. The general framework of continuum damage mechanics is used to consider the impact of ductile damage on the mechanical behavior. The proposed model is implemented in a finite element method solver. The material parameters are identified from an extensive experimental dataset with an inverse method. According to the results, the impact of the strain rate and the temperature on the mechanical behavior is correctly depicted. The model is then used to evaluate the impact of temperature on strain localization. The role of the local texture on the development of ductile damage is also discussed for different specimen geometries. Finally, the impact of heat exchanges on the mechanical behavior at low and high temperatures is investigated.