Modelling of microcracks initiation and evolution along interfaces of the WC/Co composite by the finite element method

The paper presents results of a numerical analysis of micropore and microdefect evolution in the WC/Co ceramic composite under tension. The paper offers a comparison of two methods for modeling the continuum damage process of the Co metallic interface material: the XFEM (eXtended Finite Element Method) and Ductile Damage Criterion (Rice&Tracey theory). In both models, the effect of initial porosity of plastic interface material on mechanical properties of the composite using the Gurson-Tvergaard model. In particular, 2 mechanisms: (1) Void nucleation and (2) voids growth were included in the analysis. Microcracks were formed as coalescence process of the voids. The numerical calculations using the finite element method was conducted on the developed two-dimensional (2D) models, with generalized plane strain taken into consideration. The numerical analysis was conducted using the Abaqus software. Results proved a qualitative convergence of the described methods, while showing at the same time certain limitations of the XFEM model in the analyses based on the 2D models.