Strain rate effect on the fracture toughness of carbon/epoxy composite in a deep-sea environment

Abstract

For a present study, the compressive fracture behavior of carbon/epoxy laminated composite subjected to low and high strain rates in the hydrostatic pressure environment was investigated. Compressive fracture tests were performed in the hydrostatic pressure environment of 270 MPa. The fracture properties, compliance and fracture load were determined from load-displacement curves as a function of applied strain rate. Elastic work factor approach was used to determine fracture toughness. It was found that fracture behavior of carbon/epoxy composite is affected by the strain rate. The compliance decreased as the applied strain rate increased while the fracture load is less affected by the strain rate. Fracture toughness decreased about 13% as the strain rate increased from 0.05% to 0.55%. It seems that the decrease of fracture toughness with increasing strain rate occurs because epoxy behaves in a more brittle manner at a high strain rate.