Hypervelocity impact experiments in iron alloy targets

Abstract

In this work, we conducted hypervelocity impact experiments on iron alloy targets (FeNi36 and stainless steel SS304) at various impact angles using a two-stage light-gas gun. Our investigation focuses on the structure of impact craters formed on metallic targets, with implications for understanding potential crater formation on metal asteroids, such as those on Psyche. Our results show distinct differences in the crater morphologies of FeNi36 and SS304 targets, particularly in terms of crater size and rim features, which can be attributed to variations in material properties such as hardness and strength. We derived empirical equations from both our current experiments and previous studies with a wide range of iron alloy targets to estimate crater diameter and depth. The experimental results from our oblique impacts on iron alloy targets demonstrate that the variation in crater dimensions (i.e., depth, length, and diameter) primarily follow a sinθ relationship with respect to the impact angle. For metallic targets at oblique impacts, the material properties of both the projectile and target exert a significant influence on crater morphology, particularly at low impact angles, where they notably affect crater length. These findings may provide additional understanding of crater formation process on metal asteroids, such as those on the Psyche asteroid.