Experimental investigation on the ballistic performance of B₄C/Aramid/UHMWPE composite armors against API projectile under different temperatures

In the design of lightweight composite armor, it is crucial to consider the challenging conditions of extreme environments encountered during service. This study proposes to investigate the effect of temperature on the ballistic performance of a B₄C/aramid III/UHMWPE composite armor system against 12.7 mm armor-piercing incendiary (API) projectiles with an impact velocity of ∼500 m/s. A series of ballistic experiments were conducted under low temperature (-40 ℃), high temperature (+70 ℃), and room temperature (+20 ℃) respectively considering two shooting distances of 100 m (long-range shooting) and 30 m (close-range shooting). The structural failure modes and associated mechanisms were identified and analyzed in detail from both macroscopic and microscopic scales. The experimental results indicate that the designed composite armor is believed to perform better than the existing design schemes in resisting the 12.7 mm half-speed API projectile on the basis of similar or less areal density. The ballistic performance of the composite armor system is significantly enhanced at low temperatures and weakened at high temperatures in terms of structural damage levels and backplate bulge deformation. The decrease in shooting distance transformed the panel failure mode essentially from non-penetration to penetration under room and high temperatures, whereas the specimens under low temperatures could prevent penetration. Both the ceramic and composite laminate materials are affected by temperature and show different microscopic damage modes, indicating the damage mechanism changes at the microscopic level. These findings provide valuable insight into the design of lightweight composite armor systems to adapt to extreme service environments.