512 Effects of Strain Rate on Microscopic Fracture Process in Carbon-Fiber/Epoxy Composite Laminates

Abstract

The microscopic fracture behavior of carbon-fiber/epoxy composite laminates was investigated by in-situ tensile tests using a specimen-with artificial notches. The effects of strain rate on microscopic crack growth behavior were discussed with comparing the present test results with the previous test results obtained by mode I interlaminar fracture toughness test. The tendency was similar between the present test results and the previous test results; the microscopic crack pass was near the interlarface between carbon-fiber and matrix resin at lower rate of strain, whereas it was mainly in the matrix resin at higher rate of strain. The subcritical growth of microscopic crack and the growing process of damaged zone were observed in front of the main crack tip.