We propose a new grinding processing method with a dual-axis-driven grinding wheel for drilling of CFRP. Although we evaluated the processing characteristics of the SiC-grinding wheel, only a maximum of 20 holes could be drilled due to clogging of the wheel. Then, we evaluated the durability of the grinding wheels using two types of electroplated grinding wheel. The results of processing experiments showed that durability of both grinding wheels was higher than the SiC-grinding wheel.

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In dry centrifugal disc finishing, the jig for fixing the workpiece is manufactured to clarify the finishing mechanism. Fixed arrangement of the workpiece is carried out in a barrel with this jig, and stock removal in each position in flowing mass is measured. In addition, the appraisal method as distribution of stock removal in the barrel was proposed, and the relations between it and finishing conditions were considered experimentally. The centrifugal disc finishing machine equipped with an inverter and allowing the disc rotation speed to be changed, and grain mixing nylon media for dry finishing and workpiece (30 mm in diameter and 20 mm in thickness) of plain carbon steel (S25C in JIS) were used for this test. The results indicated that finishing power is greater in the lower layer near the disc than the upper layer.

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Fine particle peening (FPP) was conducted on commercial pure iron to concentrate carbon-black on the surface. Carbon-black/steel hybridized particles were developed and employed for FPP to transfer the carbon-black onto the FPP-treated surface. The results indicated that FPP using the hybridized particles successfully created a modified surface enriched with carbon-black, while bonding between the carbon-black and the substrate was weak. The amount of carbon-black on the surface was slightly decreased with increasing peening time. One reason for this was likely that work hardening of the substrate suppressed the transfer of carbon-black during the FPP process. The FPP-treated surface exhibited a low friction coefficient due to the presence of the carbon-black, suggesting that FPP using the hybridized particles may improve tribological properties.

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Aluminum alloy with high malleability is used for weight-saving in automobiles and airplanes. Therefore, the processing of aluminum alloy machine parts requires grinding to produce high-quality surface characteristics and high dimensional accuracy. However, application of grinding to materials with high malleability, such as aluminum alloy, tends to result in loading of the grinding wheel. At present, grinding wheels with large-sized abrasive grains are used for the grinding process. This study was carried out to investigate the effects of ultrasonic vibration grinding on the aluminum alloy, by vibrating the grinding wheel at 30 kHz in the radial direction. Moreover, the effectiveness of ultrasonic vibration grinding was studied. The results indicated that ultrasonic vibration grinding could yield improved surface quality, with reduction of roughness, waviness, and loading.

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