Crack propagation analysis for orthotropic non-homogeneous materials

Abstract

The fracture mechanics of orthotropic non-homogenous materials like welds involves the use of a fracture criterion with the stress analysis of the specimen. A maximum energy release rate criterion is proposed in this analysis. A finite element model with special crack tip elements has been developed for this study. Two techniques have been developed to model the crack propagation. The model was then applied to a compact tension specimen with a hypothetical weldment and to a weldment with an edge crack. The maximum energy release rate criterion seems to be the most suitable for fracture prediction of non-homogeneous materials, since it gives the crack propagation direction as well as the maximum value for the energy released. The virtual displacement technique for modeling the crack propagation saves computer time and gives accurate results. The analysis indicates the effect of orthotropy on the crack propagation direction and maximum energy release rate.