Evolution of Bonding Strength of WC-10Co-4Cr Coatings during Grinding Based on a Voronoi Polycrystalline Model

Abstract

To investigate the degradation mechanism of bonding strength of WC-10Co-4Cr coatings during grinding, a Voronoi polycrystalline model combined with single abrasive grain explicit dynamic simulation and scratch experiments was employed. A coupled abrasive–coating–interface–substrate model was established in ABAQUS, and the effects of grinding depth and speed on stress distribution and load transfer were analyzed under purely mechanical conditions. Results show that increasing grinding depth intensifies stress concentration and promotes subsurface damage and interfacial degradation, leading to a reduction in bonding strength. In contrast, higher grinding speed produces a more uniform stress distribution, suppresses interfacial damage, and enhances bonding strength. The polycrystalline model further reveals that stress localization is governed by grain heterogeneity, with grain boundaries acting as preferential damage initiation sites. These findings provide insight into the relationship between grinding parameters and bonding performance, offering guidance for process optimization of WC-based coatings.