Study on the wear mechanism and cutting performance of PCD and PCBN tools in SiCp/Al machining

SiCp/Al composites are widely used in the aerospace field, but they still face numerous technical challenges due to processing difficulties and the rapid wear of cutting tools. This research investigates the wear mechanisms of PCD and PCBN tools in the SiCp/Al cutting process and systematically classifies and characterizes the wear features in various cutting regions of the tools. The research provides an in-depth analysis of the effect of tool wear status on chip morphology and surface quality. The results indicate that the presence of SiC particles results in both tools experiencing severe abrasive wear. Specifically, the flank face of the PCD tool shows abrasion and adhesion, while the rake face and cutting edge mainly exhibit chipping and abrasive wear. In contrast, the PCBN tool is affected by thermal damage, causing severe adhesive wear and diffusion wear on its surface. Notably, this research reveals the tool wear evolution of the rake face, flank face, and cutting edge. As tool wear progresses, the chips transition from a spiral to a fragmented shape, with the change occurring earlier in PCBN tools compared to PCD tools. Furthermore, the surface roughness of workpieces machined with PCD tools is consistently superior to that of those machined with PCBN tools in all wear states. These findings indicate that PCD tools outperform PCBN tools in machining SiCp/Al composites. This study offers significant theoretical insights into the selection and design of tools for SiCp/Al machining.