This paper deals with the grinding performance of SiC-based ceramic matrix composites (CMCs) with a mounted wheel. A vitrified bonded superabrasive stone was applied to grind the CMCs. To investigate the influence of grinding conditions on the machinability, the specific grinding energy and tool wear were measured experimentally. The influence of fiber orientation on the surface quality was also evaluated. In addition, the grinding performance of CMCs was compared with that of atmospheric sintered silicon carbide. The results showed that the CMCs were ground with a depth of cut of 900 μm without any wear on the mounted wheel. The machinability of CMCs was superior to that of atmospheric sintered silicon carbide. In addition, the surface roughness on CMCs was influenced by the fiber orientation.

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This study was performed to investigate the effects of kinetic energy and injection angle on the surface condition of carbide in the blast polishing process. Polishing speed showed a maximum value for 30 s after starting polishing under all kinetic energy conditions. The bottom part of the carbide surface was polished with a polishing speed that was about 75% of the flat part. Polishing speed and reduction speed of surface roughness showed maximum values at an injection angle of 45°. Reduction speed of surface roughness showed a maximum value for 150 s after starting polishing in water content rate of 10% with the smallest of kinetic energy, but the saturated surface roughness value showed a maximum value in water content rate of 10%.

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The present study provides an efficient approach for nano-functionalization of diamond powders. Boron nanostructures can be grown on the entire surface of diamond particles by a simple heat treatment process. A mixture of diamond and boron powders with addition of Cu was used as the source material. After treatment, various boron nano-forms were grown on the diamond particle surface at different processing temperatures. High-density boron nanowires (BNWs) grew on the entire surface of diamond particles at 1060°C, while nanopillars cover diamond powders when heat treatment was performed at 1120°C. A series of analyses, including SEM, EDS, and TEM, were employed to investigate the as-grown boron nanostructures. The boron nanostructure was confirmed to be crystalline rather than amorphous, and it was shown to have a hexagonal structure.

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The authors had developed an ultra precision cylindrical grinder with high rotational accuracy and ultrafine infeed for cylindrical mirror grinding. A mirror surface, as fine as the surface ground by an ultrafine-grained cBN vitrified bonded wheel, can be obtained in plunge cylindrical grinding by a coarse-grained cBN vitrified bonded wheel dressed by the ultrafine infeed method using the ultra precision cylindrical grinder. The mirror surface ground using coarse-grained cBN vitrified bonded wheel has high compressive residual stress by processing-induced martensitic transformation. In contrast, that ground using ultrafine-grained cBN vitrified bonded wheel did not.

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