This study deals with the machinability of BN added free-machining steel in drilling operation. Drilling is one of the most important operations in machining. Therefore, to clarify the free-cutting mechanism of BN added free-machining steel, drilling was carried out and the tool wear, cutting force, and cutting temperature were measured. Use of BN added free-machining steel resulted in less tool wear, slightly lower cutting force, and almost the same cutting temperature as compared with standard steel. Therefore, in cutting with HSS drills at low cutting speed, BN added free-machining steel shows good machinability as compared with standard steel.

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Warp accuracy and nanotopography in the silicon wafer slicing process influence the final quality of the wafer. Therefore, methods to improve these factors are important. The present study was performed to assess mechanical factors, such as machine static accuracy and thermal deformation, to improve the accuracy of multi-wire saws. The results indicated that table feed accuracy is closely connected to warp accuracy. By enhancing the straightness of the table guides, we improved component deformation. Moreover, we clarified the frame's thermal deformation characteristics, and by employing low thermal expansion materials, we improved the thermal deformation characteristics.

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The grinding wheel surface topography, characterized by the distribution of cutting edges, has a strong influence on grinding results, such as surface roughness, grinding force, and temperature. Thus, to optimize the high-quality grinding process, it is necessary to accurately measure the wheel surface topography. In this study, a new measuring system was developed for evaluation of wheel surface topography by measuring numerous microscopic images of the wheel. Using this system, it is possible to measure the distribution of cutting edges, height of cutting edges, and the form of the outermost wheel surface. In addition, image processing using a newly devised diamond wheel can extract cutting edges on the wheel surface with high accuracy and in a short time.

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Manual polishing requires several days to finish a cellular phone die and form accuracy is poor compared with machined surfaces. Finishing methods without manual polishing are required to resolve these problems. This paper reports a method of finishing molding dies by ultrasonically assisted diamond grinding. Mirror surface finishing was realized and there was little abrasive wear using ultrasonically assisted grinding.

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