An on-machine instrument that can measure the profile of an end mill was developed. This instrument has an electrical contact wire that detects the cutting edge and then calculates the properties of its profile using coordinates acquired from the contact of the wire with the cutting edge. The coordinate data are taken from the numerical control axis. This measurement method uses a wire as a stylus. The wire has a uniform cross-section and precise radius. If the contact point is damaged, it can be refreshed by winding the wire in the direction of the axis. Therefore, using a wire makes it easy to detect the cutting edge of a rotating tool. In this experiment, the radius and deviation from circularity of a ball end mill rotating at cutting speed were measured using this instrument. The measurement performance and details of measurement system developed are described in this report.

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With advances in IT and next-generation cellular phone etc., there is a demand for miniaturization and reduced-thickness mirror finished surfaces of quartz crystal parts used in these products. A quartz crystal is diced to form a small chip in the conventional process, because handling is difficult and a long time is needed. If mirror grinding of a quartz crystal wafer can be realized, the manufacturing process would be completed in a shorter time. Therefore, the silica EPD grinding wheel and alumina EPD grinding wheel for mirror grinding of quartz crystal were developed for mirror grinding applying mechanochemical reactions, and their grinding performances were investigated. A 3" wafer of quartz crystal could achieve a smooth ground surface less than 10 nmRz in10 min with the silica EPD grinding wheel and also obtain a mirror surface of 12 nmRz with the alumina EPD grinding wheel. The reaction product of the crystal and alumina was detected in the EPD grinding process. It was suggested that the mirror finishing mechanism of quartz crystal with the alumina EPD grinding wheel was achieved by mechanochemical reaction.

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The ELID mechanism of conductive rubber bonded wheel unclear/incomplete developed to enhance the finish in ELID grinding was investigated. Electrolytic dressing was carried out under various electrolytic conditions, and the results of observation of the bond material surface and friction wear experiments showed that by setting appropriate electrolytic conditions, an altered layer that decreases specific wear of the bond material surface is formed. The altered layer was analyzed, and oxygen generated in the electrolysis reaction following electrolytic dressing was found to cause oxidative cross-linking of rubber molecules and harden the grinding wheel surface. In addition, it decreased the carbon black maintaining conductivity of the grinding wheel, thereby insulating the grinding wheel surface. Based on these results, the conductive rubber bond ELID cycle was proposed. Grinding experiments were performed and the ELID cycle was confirmed to function.

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