Simulation Simulation Of Collision Effect Of Armored Ceramic Impact On Long Rod Impact

This study focuses on the interface defeat/dwell of ceramic armor impacted by long rod projectile (LRP). Theoretical analysis and numerical simulations of interface defeat have been carried out in this dissertation. A combined criterion, based on the theory of cone crack and wing crack model, has been proposed to calculate the interface defeat/penetration transition velocity. Meanwhile, numerical simulations of the interaction between ceramic armor and LRP have been conducted in AUTODYN to investigate the influence of several factors on the interface defeat and the penetration after interface defeat. The content of this paper is below:(1) Combined criterion for calculating the transition velocity from interface defeat to penetrationThe study applies the Hertz contact theory to the theory of cone crack and wing crack in order to figure out the relation between the transition velocity and the radius of LRP. A combined criterion for calculating the transition velocity has been established in combination with the strength of cone and wing crack’s theory.(2) Numerical simulation of interface defeat of ceramic armor impacted by LRPNumerical simulations of interface defeat has been carried out in AUTODYN with JH-1 constitutive model for brittle material and JC constitutive model for metal. Typical simulation results obtained have been compared with previous experimental results from the literature to verify the reliability of the numerical simulation.(3) Numerical simulation of factors affecting interface defeatThree main factors, namely nose shapes of LRP, thickness of cover plate and pre-stress, have significant influences on the interface defeat. Thus, the effect of these factors has been studied after proving the reliability of the simulation method. Parameters, like damage, pressure of ceramic, depth of penetration, etc. have been obtained and an analyzed.(4) Numerical simulation of depth of penetration of ceramic composite armor on considering interface defeatNumerical simulations of different thickness of ceramic and steel backup have been conducted to investigate the interface defeat on penetration. The optimal structure of the ceramic composite armor has been determined with the best performance in defeating LRP.