In the grinding operation, residual stock removal of the workpiece by abrasive grains occurs by elastic displacement of the abrasive grain and elastic deformation of the workpiece. Therefore, investigation of the elastic displacement and deformation allows quantitative determination of the amount of residual stock removal of the workpiece in the grinding operation. This study was performed to estimate the ground depth of cut of the workpiece taking into account the elastic displacement of abrasive grain and the elastic deformation of the workpiece in single abrasive grain grinding. Here, grinding operations with the settled depth of cut of 1μm for abrasive grain grade 60, 80, and 100 were carried out, and the ground depth of cut was examined quantitatively.

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An optical microgauge system using near-infrared spectroscopic measurements was proposed as a thickness-monitoring tool in the silicon wafer thinning process. Fabry-Pelot interferometry and Lambert-Beer's law were employed as the principles of the system for extracting the wafer thickness from optical spectroscopic system prototyped in this study. The specifications of the system, such as the thickness range (0.2μm at the minimum end) and resolution (0.2 nm) were estimated on the prototyped system. The field test verified that the developed system was available for monitoring Si wafers as thin as 8.4μm.

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The multi-wire saw is a processing method to slice solar cell wafers using wire and suspension of abrasive grains. Therefore, this method requires high-precision processing to improve the conversion efficiency or to reduce the production costs of solar cells. This study was performed to decrease the kerf loss and work damage layer as well as to study the slicing characteristics using diamond slurry and resin-coated wire. And, the result indicated that the mirror surface wafers got by this wire slicing method using diamond slurry.

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This paper deals with laser forming procedure to bend pure titanium sheets along arbitrary curved shapes. In preliminary experiments, single-straight-line bending was carried out, and the relationship between angle of bend and laser irradiation condition was investigated. The angle of bend could be controlled with the scanning velocity and the number of scanning passes. Using the experimental formula obtained by single-straight-line bending, we attempted to bend titanium sheet along a given parabolic shape with multi-straight-line bending. The experimental results corresponded well to the target shape. This paper proposed a laser forming procedure for curved shapes, including both convex and concave curves. The bending direction was controlled by defocus length of laser beam and pre-bending direction.

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We propose a new ELID grinding technique using electrolyzed reduced water as the grinding solution and conductive rubber bond grinding wheel. In this study, we performed grinding experiments on pure Ti using this system, and the fundamental characteristics of the system were investigated. The results showed that mirror surface finishing can be achieved, with a rich layer of Ca and reduced water components on the workpiece surface. Biocompatibility of the workpiece after grinding using this system was superior to that of the conventional ELID grinding system.

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