The metallurgical and deformation behaviours of laminar metal matrix composites after ballistic impact

In this study, two types of laminar metal matrix composite (MMC) samples were manufactured. Their failure mechanisms and deformation behaviours were investigated to evaluate ballistic performance. These laminated samples consist of sub-MMC layers and un-reinforced Al layers. The sub-MMC layers were MMC layers produced from particulate-Al2O3-reinforced AA 2024 aluminium alloys. These layers were manufactured using both squeeze casting and hot pressing techniques. They were laminated with un-reinforced AA 2024 aluminium alloy layers as A-type and B-type using the same techniques. The ballistic tests were carried out with a 7.62 mm × 51 mm armour piercing (AP) projectile, and the responses of the targets to ballistic impact was evaluated by examining the hole surface generated by the projectiles. A-type and B-type laminated structures showed different failure mechanisms. Deep craters occurred on both sides of the hole of the A-type target, while for B-type targets, petalling and bulging occurred at the entrance and exit of the hole, respectively.