A Note on the Effects of Voids Upon the Hygral and Mechanical Properties of AS4/3502 Graphite/Epoxy

Abstract

This paper presents the results of an experimental investigation of the effects of voids upon the hygral and mechanical properties of AS4/3502 graphite/epoxy. Simple uniaxial tension tests were employed to determine the effects of voids upon ply moduli E11, E22 and G12, and the Poisson ratio ν12. The matrix dominated moduli E 22 and G12 were found to depend significantly upon void content while little dependence was noted for the fiber dominated properties E11 and ν12. Moisture conditioning experiments showed that both the rate and the equilibrium level of moisture sorption depend upon void content. In addition, non-Fickian diffusion anomalies were observed in high void content specimens while specimens with low void content displayed classical Fickian behavior.