Vickers indentation crack propagation analysis and finite element simulation verification based on the cohesive zone model in silicon carbide ceramics

In this study, liquid-phase-pressureless-sintered silicon carbide ceramics were prepared, and Vickers indentation experiments were carried out. The crack propagation process and post-indentation morphology were observed and analyzed under different loads. The Vickers indentation process was simulated by finite element method (FEM), which ultilized the globally embedding zero-thickness cohesive elements in the modeling. The results indicated that the simulation values for the indentation diagonal length 2a, crack length 2c, and maximum indentation depth hm had a strong agreement with the experimental results. Moreover, the simulation revealed that during the initial loading phase, radial cracks and median cracks internal the sample formed simultaneously. The median cracks propagated downward and laterally, the radial cracks propagated along the indentation diagonals and internal the sample. Eventually, an obvious halfpenny crack was formed. This study provides a theoretical basis for analyzing the mechanical properties and crack behavior of silicon carbide ceramics in complex environments.