An experimental study on the projectile defeat mechanism of hard steel projectile against boron carbide tiles

• Failure studies on 7.62 mm AP after penetrating B4C tiles backed by Al6063.
• Temperature rise of 1160 °C at interaction front of the projectile is estimated.
• Shear band cracks observed at interaction front produce fine fragmentation.
• Failure along projectile axis caused by cracks initiated from projectile tail end.
• Tile thickness, projectile velocity do not change fracture features, failure mechanism.

Failure mechanism of 7.62 mm AP projectile impacting boron carbide tiles was studied by post ballistic examination of the failed projectiles. It is found that the projectile failure originates simultaneously from at least two locations in the projectile during ballistic impact, one originating from the target interaction front of the projectile and another from a location near the tail end of the projectile. The failure origination from the target interaction front of the projectile is due to severe deformation at the interaction front. The second failure origination from locations near tail end of the projectile is due to stress wave generated micro-cracks. At the target interaction front of the projectile a temperature rise of above 1160 °C has been estimated. No remarkable change in failure mechanism of the hard steel projectile with respect to tile thickness (5–9.2 mm) or projectile velocity (600–820 m/s) has been observed. The variation in remnant projectile weight with respect to tile thickness and projectile velocity can be attributed to the change in duration of dwell or total projectile interaction time with ceramic target.