Numerical Simulation Study on the Failure Behavior of Ti-6Al-4V SiC Composites

Abstract

The failure behavior of metal matrix composites (MMCs) under extreme environments involves multiple damage mechanisms of the matrix, reinforcement, and interface. Conducting high-fidelity numerical simulations of this behavior remains a significant challenge in the fields of solid mechanics and computational materials science. This paper establishes a numerical simulation framework for Ti-6Al-4V/SiC composites that combines a thermo-mechanically coupled cohesive zone model (CZM) with a ductile phase-field fracture model (PFM). By incorporating the Johnson-Cook (J-C) plasticity and damage criteria, the strain-rate dependent and thermal softening behavior of the titanium alloy matrix is accurately described. Through the development of element and node renumbering strategies, the issue of interrupted phase-field data transfer caused by the embedding of cohesive elements is resolved, enabling effective coupling of interfacial debonding and matrix fracture. The model was validated using smooth round bar tensile experiments; the simulated force-displacement response and damage evolution process show good agreement with experimental results. The results indicate that this model can reasonably predict the entire process of Ti-6Al-4V failure, from damage initiation to macroscopic fracture. This study provides an extensible modeling approach and numerical implementation pathway for the failure analysis of metal matrix composites under complex loading conditions