Characterization of Snap-Cure Epoxy Resin under Tension and Compression Loading at Quasi-static, Intermediate and High Strain Rates

Abstract

The recent development of snap curing epoxy resins, low-cost reinforcement fabrics, and automated rapid processing technologies has led to increased usage of fiber-reinforced plastic (FRP) composite materials in high-volume production vehicles. For energy absorbing vehicle structures, characterizing the strain rate-dependent response and the local failure behaviour of the epoxy material is critical to assess the crashworthiness of these FRP materials. The current study investigated the deformation response of a three-part snap-cure epoxy resin under tensile and compressive loading over a range of strain rates (i.e., 〖10〗^(-4) to 〖10〗^3 s^(-1) ). The experimental results revealed that the tensile elastic modulus and the yield strength of the tested material increased notably over the range of strain rates investigated, while all the tensile specimens fractured in a brittle manner. In contrast, the compressive elastic modulus was not sensitive to the change in strain rates; however, the compressive yield strength increased significantly and was higher than the tensile yield strength at similar loading rates. This study provides an important data set for a snap-cure epoxy material while addressing a gap in the literature, which will support the development of a robust high-fidelity virtual multiscale-modeling framework aimed at predicting the impact performance of FRP materials.