The boundary finite element method for predicting directions of cracks emerging from notches at bimaterial junctions

The analysis of a bimaterial medium with various notch opening angles has been carried out using boundary finite element method (BFEM) under arbitrary loading conditions. Introduced as novel method for stress concentration problems at geometrical discontinuities, cracks, bimaterial notches etc., the BFEM has been proved as numerically highly efficient. This has become more and more important because wedge type construction creates stress concentrations which may lead to crack initiation in many practical situations where multi-layered composite material is used, e.g. within aerospace, ship or automobile structures. So, the computational prediction of potential directions for crack initiation is essential for the knowledge of weak regions. All the analysis results are based on the hypothesis of Erdogan and Sih and have been verified by the well established finite element method. Results for potential crack initiation angles of both homogeneous and bimaterial media are presented with multiple examples of different wedge angles and different loading combinations.