Polynomical Evaluation of Stress Intensity Factors of CNS Specimen with an Interface Crack Subject to Mixed-Mode Loading

摘要

Three-dimensional finite element analysis has been carried out on the compact normal and shear (CNS) specimens under mixed-mode loading. The complex stress intensity factor K associated with an elastic interface crack is discussed by the virtual crack extension method. The effect of Young's modulus and Poisson's ratio on stress intensity factors is discussed under various kinds of mixed-mode loading. The distribution of stress intensity factors along the crack front is investigated. A polynomial fitting is proposed to evaluate the stress-intensity factors at the midsection of CNS specimen with an interface crack subject to mixed-mode loading. It is possible to evaluate the stress-intensity factors of CNS specimen with high accuracy by the present polynomial evaluation.