Strain rate effect on composites with epoxy matrix filled by cork powder

Abstract

Literature is consensual that composite materials are sensitive to the strain rate and, consequently, the design of a structure is too conservative when the static properties are only taken into account. For this purpose, three point bending static tests were performed with different strain rates at room temperature. In terms of materials, Kevlar and carbon composites with pure epoxy matrix and filled by cork powder were studied. It was possible to conclude that, for all materials, the bending stress and strain at maximum bending stress are loading rate sensitive. However, in terms of bending modulus, carbon composites with pure resin show to be insensitive to the strain-rate. Finally, the tendency observed for these properties can be supported by linear models, as suggested by the open literature.