Numerical analysis of indentation fracture in quasi-brittle materials

The process of indentation of brittle and quasi-brittle materials has been investigated both from the experimental and the theoretical point of view. As far as we know, only a few studies have tried to explain the mechanics of cutting due to an indenter which penetrates inside the material. In this paper, an attempt is made to find some general relations for the cutting process in brittle and quasi-brittle materials, under different hypotheses for the microscopic failure behaviour. Fracture patterns in homogeneous brittle solids are obtained by the finite element method in the framework of linear elastic fracture mechanics. Microstructural heterogeneities are taken into account by the lattice model simulation. Although the reality is often much more complex than the theoretical models applied, the study provides interesting indications for improving performance of cutting tools.