Studies on the Variations in Compression Strengths of Graphite Powders Bearing Glass-Epoxy Composites Exposed to Humid Conditions

Abstract

The moisture absorption and changes in compression strengths in glassepoxy (G-E) composites without and with discrete quantities of graphite powders introduced into the resin mix prior to its spreading on specific glass fabric (layers) during the lay-up (stacking) sequence forms the subject matter of this report. The results point to higher moisture absorption for graphite bearing specimens. The strengths of graphite-free coupons show a continuous decrease, while the filler bearing ones show an initial rise followed by a drop for larger exposure times. Scanning fractographic features were examined for an understanding of the process. The observations were explained invoking the effect of matrix plasticizing and the role of interfacial regions.

Keywords

compression strength glass-epoxy graphite powders humid conditions

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