Cracking wear is one of the major phenomena that affect the lifetime of cutting tools. Delamination may be the last stage and the inevitable outcome of the propagation of cracks that may initiate anywhere in the coating or at the coating/substrate interface. To explore this phenomenon, the standard finite element analysis (FEA) FEM analysis was performed, in a first step, to calculate the energy necessary for crack deflection at the interface and penetration into the substrate. The numerical results showed that the cracks are more prone to deflect at the interface than penetrating into the substrate. This prediction was supported by microscopic observations. In a second step, a numerical model was developed based on the combination of the extended finite element method (XFEM) and the cohesive element method (CEM) formulations for different parameters in relation with machining performance improvements. The findings of the parametric study enabled to conclude that the low stiffness, large edge radius, large thickness and high rake angle of the coating protect the tool from cracking. In parallel, it was revealed that a substrate with lower rigidity results in the delay of the tool crack initiation.

裂纹磨损是影响刀具寿命的主要现象之一。分层可能是最后阶段，也是裂纹扩展的必然结果，裂纹可能在涂层中的任何地方或涂层/基材界面处开始。为了探索这种现象，第一步进行了标准有限元分析 (FEA) FEM 分析，以计算界面处裂纹偏转和渗透到基材中所需的能量。数值结果表明，裂纹更容易在界面处偏转，而不是穿透到基体中。这一预测得到了微观观察的支持。第二步，基于扩展有限元法 (XFEM) 和内聚元法 (CEM) 公式的组合开发了一个数值模型，用于与加工性能改进相关的不同参数。参数研究的结果能够得出结论，涂层的低刚度、大边缘半径、大厚度和高前角可保护刀具免于开裂。同时，揭示了具有较低刚度的基板会导致工具裂纹萌生的延迟。