An Empirical Penetration Equation for Thin Metallic Films Used in Capture Cell Techniques

The problem in the determination of impact particle parameters from hypervelocity impact damage on a foil or multilayer structure is one which deserves close attention in the era of ready access to recovered space impact events. In the MFE experiment (McDonnell et al 1984), we chose metallic foils, and this paper addresses the decoding of perforations in metallic foils, primarily of aluminium of typical dimensions 5 pm (hard temper rolled). Data is examined to establish for the first time a penetration relationship which extends over: 1. marginal and thin sheet perforation; 2. velocities varying from some 2 to 69 kms-1; 3. particle densities varying from some 1 g cm-3 (ices?) to 7.8 g cm-3 (iron?)