Conventionally, cutting has been used for drilling holes in Carbon Fiber-Reinforced Plastic (CFRP). However, problems such as delamination, burr formation, and severe tool wear arise in CFRP cutting. Here, we examined drilling of CFRP by ultrasonic vibration-assisted grinding. Microfractures of carbon fibers were induced by the application of ultrasonic vibration to the grinding tool, which improved the material removal characteristics. As a consequence, the anisotropy of machinability due to fiber orientation was suppressed, and the delamination at hole edges was prevented. Furthermore, the grinding force was reduced by approximately 70% through ultrasonic vibration at the initial stage of drilling.

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Wheel scribing and breaking technology has been widely adopted for cutting of LCD glass substrates. The advantages of this technology are the lack of kerf-loss, high speed, and dry process in comparison with dicing. In addition, substrates cut by wheel scribing have no heat-affected zone, in contrast to laser cutting. Therefore, application of this method to cutting ceramic substrates is expected to reduce manufacturing costs. When alumina substrates were cut with a scribing wheel, the median crack propagation was in the thickness direction of the substrate, which also occurred in scribing glass. However, when a scribing wheel for glass was used to cut alumina substrates, the substrate could not be separated before scribing length reached 100 m because of abrasion of the scribing wheel. Therefore, we developed a new wheel for ceramic substrates, which has good abrasion resistance. The tool life of the wheel for ceramic scribing was ten times longer than that of the wheel for glass scribing.

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TiB₂ base thin films have been prepared by DC magnetron sputtering with a sintered TiB₂+B target to obtain high cutting performance against stainless steel used as an airplane material. The critical loads (adhesive strength) and microhardness of TiB_2+α films were higher than those of TiB₂ films. The TiB_2+α-based Ti-B-C films with C content of about 50% had good frictional properties compared to TiB_2+α film, and the friction coefficients decreased from 0.8 to 0.4. Cemented tungsten carbide cutting tools were coated with Ti-B-C film with high adhesive strength, high hardness, and low frictional properties. Chips formed with the Ti-B-C coated tool were smoother than those formed with uncoated tools.

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