Glass Fabric Vinyl-Ester Composites: Tailoring the Fiber Bundle/Matrix Interphase with Nylon Coatings to Modify Energy Absorption Behavior

Abstract

The influence of a polyamide coating on the energy absorption behavior of an E-glass fabric-Vinylester composite was investigated using low velocity impact events to assess composite response. The evaluation included three different plate thicknesses and two concentrations of polyamide to achieve a thin and thick coating of the fabric reinforcement. Inelastic Energy Curves (IEC) were used to describe and compare the dominant failure modes. Thin ductile coatings were seen to enhance energy absorption primarily through crack blunting and enhanced frictional sliding, while thicker coatings appear to facilitate delamination in addition to matrix-coating slip due to the weak chemical bond between the vinylester matrix and polyamide. These mechanisms combine to allow greater plate deflections which in turn induce transitions between the dominant plate reactions and ultimately translate into greater energy absorption.