In this study, the relation between tool flank temperature and surface roughness in turning of sintered steel was examined. The tool flank temperatures of CBN and ceramic tools were measured by a two-color pyrometer with an optical fiber. In dry turning, the CBN tool in turning of sintered steel showed a higher temperature by 50°C－120°C compared with that of carbon steel. The higher thermal conductivity cutting tool showed lower tool flank temperature. The temperature mitigation effect of coolant was remarkable in turning with the higher thermal conductivity cutting tool. The surface roughness decreased with tool flank temperature. At the same tool flank temperature, smaller surface roughness was obtained in wet turning compared with dry turning.

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We investigated the use of data mining methods to help engineers decide on end-milling conditions. The aim of our research is to find new knowledge by applying data mining techniques to a tool catalog data. We used hierarchical and non-hierarchical clustering methods as well as principal component analysis and multiple regression analysis. We used the K-means method and focused on the shape presented in the catalog data, and grouped end-mills from the viewpoint of the tool shape, i.e., the ratios of its dimensions. We decreased the number of variables by variable cluster analysis. In addition, we found an expression for calculating cutting conditions and compared the calculated values with those in the catalog. There were three end-milling conditions: conditions recommended in the catalog, conditions derived by data mining, and proven cutting conditions for die machining (rough processing).

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The grinding process is a very efficient machining technology because innumerable abrasive grains are fixed on the surface of the grinding wheel. In particular, the distribution and shape of the cutting edges, which directly affect the grinding process, have a big influence on accuracy. Thus, it is very important to measure the wheel surface topography from the viewpoint of evaluating the wheel life and the performance and the relation between the topography and the roughness. In this study, a three-dimensional measurement system of a grinding wheel surface with image processing is developed. In this system, the distribution and height of cutting edges are analyzed because only cutting edges can be selected from among all abrasive grains.

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A viscoelastic polymer with high scratch resistance was developed as a product coating material. However, it is difficult to finish the polymer-coated surface due to its characteristics, such as viscoelasticity. Thus, polishing is carried out by trained technicians and depends on the skillful adjustment of the polishing pressure according to the situation. To realize automation of polishing, high-precision and highly responsive force control is required. Typically, force control is done with force sensors. However, use of external sensors is associated with problems, such as high-cost, reduction of machine stiffness, and thermal drift. The thermal drift, which is caused by polishing heat, prohibits accurate measurement of force. The purpose of this study was to develop a polishing pressure control method without any additional sensors. In addition, the control method was applied to a buffing machine, and buffing performance of viscoelastic polymer was experimentally analyzed.

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Cutting and friction experiments were conducted in various atmospheres to investigate the chemical effects on textured cutting tools. Cutting experiments of aluminum alloy indicated that the atmosphere affected the machinability of the textured tools; a larger effect was observed in the presence of gases, such as oxygen. A ball-on-disk friction apparatus was developed and used for the friction experiments. The texture effect was observed in the presence of oxygen－this trend was similar to that observed during the cutting experiments. These results indicate that oxidation is an important factor in determining the texture effect for machining aluminum alloy.

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