EXPERIMENTAL LAWS OF CRATERING FOR HYPERVELOCITY IMPACTS OF SPHERICALPROJECTILES INTO THICK TARGET

It is shown in this paper that the laws of cratering in a thick target under hypervelocity impact by a spherical projectile can be approxima tely expressed by the so-called iso-deviation law and a 2/3 power law. Moreover, hypervelocity impact should be characterized by the isotrop ic expansion of a crater. In the special case, when the projectile and target are of the same material, the laws mentioned above reduce to t he result of a semi-spherical crater and the energy criterion. General ly speaking, a semi-spherical crater and the energy criterion are both approximations, which only take projectile density and target strengt h into account, and can be used for a rough estimation on the order of magnitude. The inconsistency in various fitted power laws in the lite rature was also clarified and explained in the paper.