Influence of the target temperature on the protective strength of steel plates

Within the scope of acceptance tests for small arms ammunition it was observed that the ballistic protective strength of steel plates increased with decreasing temperature of target plates. In order to explain this phenomenon armor piercing bullets were fired against structural steel plates at temperatures between -20 degreese and +80 degreese. Both pointed and blunt projectile impacts were simulated. The observed residual velocities and the ballistic limit values show a significant dependence on temperature. For pointed projectiles the protective strength was found to decrease with increasing temperature. However, when firing blunt projectiles a positive slope was observed. The thermal effects can be explained by analyzing the material response to pendulum impact tests.