Hypervelocity impact of dual-wall space structures with graphite/epoxy inner walls

Abstract

The design of a spacecraft for an earth-orbiting mission must take into account the possibility of high-speed impacts by pieces of orbital debris and their effects on the spacecraft structure and on all of its exposed subsystem components. This paper presents the results of a preliminary experimental investigation in which the perforation resistance of dual-wall structures with aluminum outer walls and graphite/epoxy inner walls was compared against that of all-aluminum structures under simulated orbital debris impact loadings. The advantages and disadvantages of using graphite/epoxy as the inner wall material of a dual-wall structure are presented and discussed. The analyses performed showed that the effectiveness of the graphite/epoxy panels varied significantly depending on the velocity of impact. Based on the results obtained, the primary advantage of using graphite/epoxy as the inner wall material appears to be that it eliminates the severe cracking and petalling sustained by aluminum inner walls in dual-wall systems with internal multi-layer thermal insulation.