Effects of dynamic prestress on silicon carbide ceramic against long rod impact

Abstract

It is well known that silicon carbide (SiC) ceramic is a pressure dependent material, where the compressive strength increases as the pressure increases. So, it is an effective way to improve the ballistic performance of SiC ceramic by introducing prestress on ceramics surface. In this paper, the concept of dynamic prestress on SiC ceramic by energetic materials was proposed. Five key factors, including the time of projectiles contact targets, velocity of the long rod projectiles (V p), prestress rising stage time (T r), prestress descent stage time (T d) and peak pressure of prestress (P k), were selected to investigate the effect of dynamic prestress on SiC ceramic targets against long rod impact. The effect of dynamic prestress on the ballistic performance of SiC ceramic were investigated, and the dynamic prestress path which can increase the protection capability of SiC ceramic was given. The results indicated that, in most cases, the ballistic performance of the dynamic prestressed SiC ceramic targets against long rod projectiles impact was improved. However, it was also revealed that not all dynamic prestressing can improve the ballistic performance of SiC ceramic targets. It will be benefit to the ballistic performance of SiC ceramic by controlling the prestress time to make sure the moment of the long rod projectile impacts the target in between T 2 and T 4. The sequence of influence degree of each factor on the erosion length of long rod projectile is the velocity of long rod projectiles (V p), prestress descent stage time (T d), peak pressure of prestress (P k) and prestress rising stage time (T r). The erosion length of long rod projectile decreases with the increase of V p, and increases with the increase of prestress descent stage time (T d), peak pressure of prestress (P k) and prestress rising stage time (T r).