Nitric acid etching, which is the conventional method used in manufacturing plants to detect grinding burn, has a number of problems as follows: (1) detection level varies depending on the operator and the equipment used; (2) the tested pieces must be scrapped as it is a destructive inspection; and (3) outflow of defective products cannot be prevented perfectly as 100% inspection cannot be carried out. This study was performed to develop a non-destructive inspection system to detect grinding burn, which can be used to perform quantitative 100% inspection within a production line. For this inspection, an eddy current sensor is selected because of its short measurement time and low cost. In this paper, a new method that simultaneously measures eddy currents of two different frequencies is proposed. This method reduces the misdetection of grinding burn by eliminating the effect of variance in base material.

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In this study, we performed ELID grinding on surgical steel and evaluated the processing characteristics and resulting surface properties. In particular, we used different alumina abrasives to investigate the effects of grinding parameters on the surface hydrophilicity of the processed workpiece. The results confirmed that a surface processed with amorphous aluminum abrasives in grinding fluid at temperatures over 50℃ have the highest hydrophilicities. Moreover, they also exhibit excellent corrosion resistance. It is highly significant that the amount of abrasive components diffused into the workpiece surface can be adjusted and that surface properties such as hydrophilicity and corrosion resistance can be controlled by appropriate selection of the type of abrasive, crystallization conditions, and processing conditions, as described in this paper. Furthermore, the present technology has potential for application to various other fields, such as improving stain resistance, if used for manufacturing ultra-precision molds made from materials such as stainless steel.

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The influence of tool form and cutting conditions on the machinability of carbon fiber-reinforced polymer (CFRP) materials was examined using two-dimensional cutting visualization equipment. Orthogonal cutting equipment was improved to CFRP materials. The experiments involved changing tool form and cutting conditions, and evaluating cutting force as well as examination of processing side, scraps, and cutting action. While clarifying the machinability of cutting at the time of processing of CFRP material, a tool form suitable for CFRP processing is proposed.

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Glass and ceramics are typically hard, brittle materials, so if the depth of cut is less than the ductile/brittle transition critical depth, dc, it can be machined in a ductile mode. This paper describes the development of an ultra-precision lathe to achieve ductile mode cutting of glass. To achieve ductile mode cutting of glass, the machine tool must have positioning resolution and motion accuracy at the level of several tens of nm with high rigidity and high stability. We developed an ultra-precision lathe to clarify the techniques necessary to achieve the above performance. We examined combinations of existing technologies and developed basic elements. Finally, we succeeded in the development of an ultra-precision lathe that can machine glass in ductile mode.

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