Impact dynamics of tool steel penetrators

Armor-piercing (AP) ammunition generally carries a hard penetrator within a copper jacket. Upon impact on a hard target, the copper case is destroyed, but the penetrator continues its motion and pierces the target. The most efficient AP ammunition is built with penetrators made from either tungsten alloys or depleted uranium, but alloy steel penetrators are also commonly used, because they are less expensive and less polluting, even if they are much less efficient. The impact deformation and fracture behavior of armor-piercing penetrators fabricated with three tool steels, and their resultant ballistic efficiency, are investigated, both to better understand the optimal mechanical properties of armor piercing materials, and to describe the fracture mechanics of the tested materials. Moreover, the ballistic results of the three tool steels are compared with those of plain medium-carbon steel and cemented tungsten carbide.