Various methods of numerical estimation of generalized stress intensity factors of bi-material notches

Abstract

The study of bi-material notches becomes a topical problem as they can model efficiently geometrical or material discontinuities. When assessing crack initiation conditions in the bi-material notches, the generalized stress intensity factors H have to be calculated. Contrary to the determination of the K-factor for a crack in an isotropic homogeneous medium, for the ascertainment of the H-factor there is no procedure incorporated in the calculation systems. The calculation of these fracture parameters requires experience. Direct methods of estimation of H factors need choosing usually length parameter entering into calculation. On the other hand the method combining the application of the reciprocal theorem (Psi-integral) and FEM does not require entering any length parameter and is capable to extract the near-tip information directly from the far-field deformation.