To make a grinding wheel for nano-precision grinding, it is necessary to achieve fine-grained and uniformly dispersed abrasive grains in the bonding material. However, fine grains tend to become massed together, and variations in grain sizes of both abrasives and particles of bonding material have negative effects on abrasive dispersion. Here, some new techniques are proposed to disperse agglomerated grains, to classify fine grains, and to mix abrasive with bonding material. Based on the experimental results, a grinding wheel in which well-classified diamond abrasive grains are uniformly dispersed in resin bond was obtained.

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Environmental problems have become serious issues associated with industrial development. Cutting oil and grinding oil containing several chemicals are used as machining fluid, and there is concern regarding environmental problems associated with their presence in effluent. Therefore, a rust preventive machining method using only water as the machining fluid has been developed. Water differs in dissolved components depending among various regions of the world. However, insufficient attention has been paid to verification of the influence of these components with changes in water. Therefore, rust prevention experiments were conducted with water from five different sources. The results indicated that even when the water is changed, workpiece rust prevention is possible with electrical power-saving. In addition, the generation of white scale on the cathode surface was confirmed. Moreover, the electrical characteristics of the water from each source were measured.

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The affected layer generated by grinding or lapping influences subsequent finishing efficiency and quality. In this study, nanoscratching, which is simpler than grinding or lapping, was used to study the influence of the affected layer generated by pre-machining on the finishing process. The influences of the pre- and post-machining conditions on the scratches were evaluated by scratching the scratched region on a Si wafer with a monocrystalline diamond probe. Molecular dynamics simulation was also performed to clarify the phenomena occurring within the Si wafer using similar materials to those used in the experiments. The results confirmed that the depth of the affected layer increases with pre-machining load. It was also clarified that material removal changes from only the affected layer to a combination of bulk and the affected layer with increasing post-machining load, and the scratches became deeper with increasing ratio of affected layer removal. Finally, a machining model of the affected layer is proposed.

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Barreling is common used for deburring or surface finishing of small parts. Particularly, centrifugal barrel machining has greater efficiency than other barreling methods. It is possible to finish or deburr workpieces with high performance capabilities and short machining time. We propose a theory of inclined high-speed centrifugal barrel finishing, and carried out experiments with a prototype. The results indicated a maximum speed of 1000 min^-1 gave the best results with a 45° inclination in a previous paper. Here, we calculated and visualized the acceleration distribution in the barrel in more detail than discussed in the previous report. In addition, the turret rotation speed was increased to 2000 min^-1. Barrel processing capabilities were evaluated. The results confirmed the high capability of deburring in the experimental results of the deburring of stainless steel (SUS304).

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