High-speed penetration of a projectile into aluminum alloys at low temperatures

In order to elucidate the impact-induced fractures of materials used in outer space and manufacturing plants in low-temperature environments, the penetration and perforation of three kinds of aluminum alloys, A2017, A7075, and A5056 at room temperatures and low temperatures in the velocity range from about 500 m/s to 1.8 km/s were investigated experimentally. Main interests were focused on the depth and diameter of craters and experimental equations for the relationship between them and impact velocity were proposed. Also, microscopic observation of the recovered specimens and some numerical simulations of the penetration process were made. As a result, very distinctive features of the temperature effect on the high-speed fractures were found.