Comparative Study on Micro-Grinding Performance of 2.5D Cf/SiCs, 2.5D SiCf/SiCs, and SiC Ceramics

Abstract

To investigate the micro-grinding process and performance of 2.5D Cf/SiC composites and 2.5D SiCf/SiC composites in depth, single-factor micro-grinding experiments were conducted by using SiC ceramics as a comparison. Differences in the material removal process, surface microstructure, surface roughness, and grinding force of the three materials under the same grinding parameters were comparatively analyzed. The results indicate that crack propagation is severe during the micro-grinding process of SiC ceramics. The ground surface is uneven, accompanied by pit defects and large surface roughness Ra. However, the presence of reinforcing fibers and interfaces in the two types of composites can inhibit crack propagation or change their extension directions. Therefore, their surfaces are smooth and flat after grinding, with small defects and low surface roughness Ra. In addition, the grinding processes of the two composites are both related to fiber orientation. There are differences in crack propagation paths and fiber fracture positions in the weft fiber layer and the radial fiber layer, which result in different forms of grinding defects. During micro-grinding, the real-time force signals of 2.5D Cf/SiC composites and 2.5D SiCf/SiC composites are relatively stable, while the signals of SiC ceramics have a large number of spikes. The average micro-grinding force of the three materials is: SiC ceramics > 2.5D SiCf/SiC composites > 2.5D Cf/SiC composites.

Study on grinding removal mechanism and subsurface damage of bionic layered graphene ceramic matrix composites

“…Xiao et al [12] investigated the surface microstructure and mechanical properties of fiber toughened ceramic matrix composite parts by ultrasonic vibration assisted grinding and analysed the influence of the grinding process parameters on the surface roughness, and then optimized the grinding process parameters. Wen et al [13] investigated the microgrinding process and properties of 2.5D Cf/SiC and 2.5D SiCf/SiC composites in a single factor microgrinding experiment with SiC ceramics as a reference. The results show that the presence of reinforcing fibers and interfaces in both composites inhibits crack extension or changes its extension direction.…”