Fracture modes in off‐axis fiber composites

Abstract

Abstract Criteria have been developed for identifying, characterizing, and quantifying fracture modes in high‐modulus graphite‐fiber/resin unidirectional composites subjected to off‐axis tensile loading. Procedures are described which use sensitivity analyses and off‐axis data to determine the uniaxial strength of fiber composites. It was found that off‐axis composites failed by three fracture modes, which produce unique fracture surface characteristics. The stress that dominates each fracture mode and the load angle range of its dominance can be identified. Linear composite mechanics is adequate to describe quantitatively the mechanical behavior of off‐axis data are comparable to those measured in uneasily tests.