A Dynamic Impact Simulation Method for Titanium-Based Functionally Graded Composites Based on Abaqus/Explicit:...

Homogeneous TC4 titanium alloy suffers from the strength-ductility trade-off and exhibits insufficient anti-penetration capacity under high-strain-rate impact. TiC_p-reinforced functionally graded titanium matrix composites (FGTMCs) with a "hard outer, tough inner" gradient architecture are promising lightweight armor materials. The use of Abaqus/Explicit finite element simulation for FGTMCs under dynamic impact can capture transient deformation and damage evolution while enabling rapid evaluation of the impact resistance of different materials; however, research in this area remains scarce. This study conducts a systematic parametric analysis of key simulation parameters, including calibration of the Johnson-Cook constitutive and damage model parameters for TC4 titanium alloy, optimization of mesh partitioning strategies, hourglass control schemes, model dimensions, and boundary conditions to suppress "ghost mesh" numerical artifacts. Material property assignments for TC4 and three typical titanium matrix composites are designed, along with a methodology for constructing functionally graded material models. Two projectile-target matching configurations (small projectile/thin target vs. large projectile/thick target) are compared, and the optimal model of a 700 m/s small-caliber tungsten projectile impacting a 50 mm TC4 target is identified. Parametric analysis demonstrates that a damage parameter D4 = 0.1 significantly improves numerical stability, and a graded mesh strategy with further refinement along the penetration path balances computational accuracy and efficiency. Using the optimized material system, the simulation results reproduce the three-stage damage evolution of titanium alloys under impact-cratering, plastic penetration, and back-face spallation-providing reliable numerical support for the structural optimization of graded armor materials.