Abstract Cracks on the interface of the bimaterial could be present either as a result of the manufacturing defects, and/or mismatch between the different material properties of the bimaterial. The asymptotic near-tip field for bimaterial interfacial cracks presents an oscillatory behavior which is very different from that for cracks in homogeneous materials. Due to the oscillatory behavior related to the complex eigenvalues, modeling such interface cracks by the conventional solution procedures designed for homogeneous materials is inadequate, and may not lead to accurate solutions by using the well-established and widely applied finite element method (FEM) or boundary element method (BEM), even when a very fine mesh near the crack-tip is employed. In the present paper, we document the attempt to apply the generalized finite difference method (GFDM) for fracture analysis of bimaterials containing interfacial cracks. The main idea of the method is based on the theories of local Taylor series expansion and moving-least square approximation. Since the method is meshless and no element connectivity is needed, it can be viewed as a competitive alternative for bimaterial interface crack analysis. In our calculations, a multi-domain technique is employed to handle the non-homogeneity of the dissimilar materials, and the displacement extrapolation method (DEM) is introduced to compute the complex stress intensity factors (SIFs) for cracked dissimilar materials. An improved GFDM formulation is proposed to further improve the accuracy and stability of the GFDM for fracture mechanics analysis. Two benchmark numerical examples are well studied to demonstrate the accuracy and stability of the present method for interface crack analysis of composite bimaterials. In the following-up works, other interesting and important problems, such as thermal effects and dynamic effects, and crack propagation and arrest should be considered. The present work provides an efficient alternative and the corresponding results form a solid basis for these interesting research topics.
Received: 13 December 2021
Published: 28 October 2022