Failure Mechanisms of Woven Carbon and Glass Composites

摘要

Stress-Strain repsonses in tension, compression, and shear of a fiver-harness satinweave carbon/epoxy composite and a four-harness satin-weave glass/epoxy composite have been examined. Damage progression under tension was examined by optical microscopic inspection of woven-fabric composites were examined and correlated with the experimental data. Damage inspection of the carbon/epoxy composite under tension revealed that the initial failure was cracking of pure matrix regions followed by transverse bundle cracking. Fill/weft debonding and longitudinal splits of the fill bundles occured close to ultimate failure of the coomposite. The glass/epoxy composite displayed damage in the form of fill/weft debonding and longitudinal splits, but no transverse yarn cracking. The damage observed in both composites was confined to the region where ultimate failure occurred. Elastic properties of the composites were overall in good agreement with micromechanical predictions based on uniform strain, but failure stress predictions were less accurate.