In dry centrifugal disc finishing, the pressure sensor is manufactured to clarify the finishing mechanism. As the radial pressure is nearly zero in every part of the barrel, the circumferential pressure is defined as the finishing pressure. The distribution of the finishing pressure in the radial direction and the height direction of the barrel is investigated with this pressure sensor. The following results are obtained. Although the finishing pressure becomes high with increasing radius, it begins to decrease near the side wall of the barrel. It increases with increasing disc rotation speed and media charging rate.

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There is increasing demand to reduce friction in engine and transmission parts. Friction between sliding surfaces can be reduced by processing micrometer-scale surface textures with controlled cross-sectional geometry. We have developed 3-dimensional micro-forming technology, to fabricate such controlled surface textures at high efficiency. Here, we present the high-efficiency micro-texturing method Micro-Form Rolling (MFR), and discuss the machining properties of MFR. MFR could be used to machine 3-dimensional micro-textures with high efficiency. Furthermore, tool life of MFR could be improved by controlled the tool shape.

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Conventional dental treatment, which is usually conducted through cavity preparation and filling with dental material, has a significant risk of secondary caries. To avoid this risk, a new dental treatment using powder jet deposition (PJD) has been proposed. PJD is a coating process using accelerated particles, and hydroxyapatite (HA) particles are directly impacted for the creation of HA films on human teeth. In this study, the behavior of HA particles impacting against the bottom of a cavity was visualized through a computational fluid dynamics (CFD) method. The simulation results clarified the impact speed distribution and the ratio R of the particles impacting the bottom to the total blasted particles. PJD experiments were then conducted to ascertain which simulated parameter contributes to actual deposition efficiency. The experimental results indicated that the ratio R has a negative correlation with the blasting distance, and a blasting distance of 1 mm provided the most efficient treatment.

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