Characteristic features of the phenomenology of the perforation of composite materials

Abstract

1. Fundamental laws governing the phenomenology of the perforation mechanics of composite materials in a polymer matrix are brought to light as a result of the complex experimental investigation that we conducted on basic parameters linking the perforation characteristics of metallic alloys and composite materials in the subcritical and post-critical velocity regions of high-speed impact. 2. A new variant of the phenomenological relationship between Δv/vcr and ven/vcr is proposed and approved for comparative analysis of the ability of materials to resist perforating action. The existence of the continuity of this relationship for composite materials in the post-critical region is demonstrated in an example of fiberglasses and carbon-fiberreinforced plastics. 3. The fact of significantly higher indicators of the ability of glass mats to resist erforating action as compared with corresponding polymerized fiberglasses is, established for equal small ϱh values. The greater ability of glass-mat-base fiberglasses to resist perforation is observed for the higher perforation resistance of glass mats. The specific resistance of titanium alloys is somewhat higher than that of fiberglasses; the reverse effect is observed, however, for small and also extremely large ϱh values. 4. As for metallic alloys, the perforation curves of composite materials in (h/d, (vcr/c)(ρpr/ρob)1/2) coordinates are straight lines, which form a beam, in the impact-velocity region under investigation. 5. It is proposed to compare the residual-strength characteristics of the materials in objects after a high-speed impact event for equal values of the ratio ven/vcr. It is shown that fiberglass formed from T-10-80 fabric and epoxy binder EDT-10 is extremely sensitive from the standpoint of strength reduction to failure over the entire range of impact velocities in both the subcritical and post-critical regions, having observed the maximum softening in the vicinity of the critical velocity. After passing the critical velocity, the residual strength increases, emerging thereafter at a stationary level.