The effect of interface properties on the mechanical behaviour of 3D braided composites under unidirectional tensile loading

The mechanical behavior of 3D four-step braided composites under tensile loading is studied by computational micromechanics. Interfacial damage is considered by cohesive zone model in FEA of a representative volume cell (RVC) of the braided composites. A parametrical study is evaluated the influence of interfacial properties on the stress-strain curve and corresponding failure modes. The damage development of the braided composites with interfacial damage is discussed. It is found that the interfacial damage which is one of factors to cause the nonlinear stress-strain relation can decrease the tangential modulus but not control the ultimate strength.