It is shown in this paper that the laws of cratcring in a thick target under hypervelocity impact by a spherical projectile can be approximately expressed by the so-called iso-deviation law and a 2/3 power law. Moreover, hypervelocity impact should be characterized by the isotropic expansion of a crater. In the special case, when the projectile and target are of the same material, the laws mentioned above reduce to the result of a semi-spherical crater and the energy criterion. Generally speaking, a semi-spherical crater and the energy criterion are both approximations, which only take projectile density and target strength into account, and can be used for a rough estimation on the order of magnitude. The inconsistency in various fitted power laws in the literature was also clarified and explained in the paper. © 1993 Pergamon Press Ltd.
Shanbing, Y., Gengchen, S., & Qingming, T. (1994). Experimental laws of cratering for hypervelocity impacts of spherical projectiles into thick target. International Journal of Impact Engineering, 15(1), 67–77. https://doi.org/10.1016/S0734-743X(05)80007-7