Flow behavior of diffusion bonding interface of Ti6Al4V alloy over a wide range of strain rates

Abstract

Quasi-static and dynamic tensile tests were conducted to measure diffusion bonding (DB) interface strength of Ti6Al4V alloy at different strain rates. The effect of strain rate on fracture mode was analyzed by the fractography analyses. A modified Johnson-Cook (JC) model was proposed to describe the stress-strain behavior of DB interface, where the strain rate hardening coefficient had a nonlinear relationship with the strain and the strain rate. The JC failure model with calibrated material constants was used to predict the failure strain of DB interface. Using Abaqus/Explicit through a VUHARD subroutine, the modified JC model and the JC failure model were verified by predicting load-elongation curves and failure strains at three strain rates. The models are capable of describing the mechanical behavior of DB interface for Ti6Al4V alloy.