Dry cutting technology without cutting oil is required in order to decrease environmental burden and to reduce processing cost. In this research, for the purpose of establishing dry drilling process with indexable insert drill, we investigated basic characteristics of dry drilling and experimented several methods to suppress tool wear. As the results, in drilling conditions where the initial feed rate change to low near the exit of the hole during the drilling processes, the highest temperature of the inserts goes down, and a minimum point of the highest temperature of the inserts was shown at the optimal change position of feed rate. In these minimum points, the rake face wear became minimum, and was influenced to the highest temperature of the inserts. It is thought that the change position of feed rate at the minimum points are determined by the drilling depth.

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A new high-performance lapping tool consisting of short metallic fibers and epoxy resin was developed to overcome the low lapping performance of conventional tools for grinding difficult-to-cut materials. The short metallic fibers were compressed and impregnated with epoxy resin to produce the new lapping tool. By using these different wear-resistance materials, the tool surface could maintain the uneven shape continuously even when its surface was worn and this makes it possible to maintain long-term high lapping characteristics and enough effective slurry supply. In this research, we examined the optimization of the shape and the material of fibers. Moreover a 40 vol% fiber lap could be produced by using a coupling agent. The results of the tests showed that the lapping efficiency was improved by 28 % and that the durability was equal to that of the conventional cast-iron lap.

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The quality of the machined surface of low-rigidity elastomers by cutting under room temperature is generally considerably poor due to a large-scale viscoelastic deformation occurring around the cutting edge. In order to improve the cutting performance, this study examined the possibility of the indirect suppression of the large-scale deformation by controlling the friction properties for the rake and the flank faces by the parallel micro-grooves. The workpiece was an ester urethane rubber with a Shore A hardness number of 50. This study experimentally investigated the influences of the orientation of the grooves and the interval of a groove on the cutting performance under the cutting speeds ranging from 5 m/s to 10 m/s. The following findings were obtained; the grooves on the rake face reduce the cutting force significantly. For the flank face, the groove orientation affects remarkably on the contact state between the flank face and the machined surface. The grooves fabricated perpendicular to the cutting edge on the flank face is able to improve the shape of the machined surface. Parallel micro-grooves on both the rake face and the flank face improve significantly cutting performance of low-rigidity elastomers performed under a cutting condition with a cutting speed of less than 10 m/s and with a temperature of room temperature.

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The effect of cutting parameters on machinability of an amorphous nickel-phosphorus (Ni-P) alloy in microfabrication processes was studied. Burr and chipping generation phenomena in the microfabrication processes of Ni-P were observed and compared with those observed in microfabrication of oxygen-free-copper and aluminum alloy 7075. Experimental results demonstrate that slippages during the chip formation processes play an important role in the burr and chipping generations. Under a condition generating less slippages, the related deformation zone expands and partially protrudes along the tool-passing path. The protruded area remains on edges of generated patterns or removed, which form burrs and chippings, respectively. The deformation expansion decreases the stability of the slippage occurrence, which thus also causes unstable burr and chipping generation. The slippage occurrence in the microfabrication of Ni-P alloy is confirmed to be small, stable, and periodic. All experimental results indicate that Ni-P has an excellent machinability.

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This study deals with a sliding burnishing process with driven rotary tool used to generate smooth surfaces and enhanced layers. In conventional burnishing, a diamond tipped tool is used. In this investigation, coated carbide tools are proposed as an alternative. A previously developed hybrid-type parallel mechanism is used as a burnishing machine. Uncoated carbide tool, titanium nitride, and diamond-like-carbon coated carbide tools are used, and a stainless steel with a flat surface is targeted. The burnished surface characteristics are mainly evaluated by analyzing the surface appearance, roughness, glossiness, and residual stress of the surface layer. The tool wear behavior of the diamond-like-carbon coated carbide tool is also clarified. It was found that sufficient surface appearance, roughness, and glossiness can be obtained by using the diamond-like-carbon coated tool, which has smooth surface, high hardness, and low chemical affinity with workpiece material. High compressive residual stress can also be achieved with the diamond-like-carbon coated carbide tool while martensitic transformation of the workpiece material is prevented. The occurrence and growth of the partial multiple peeling are observed in diamond-like-carbon coated tool, and the burnished surface roughness and glossiness is drastically deteriorated by contacting between the workpiece and base material of the tool.

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The measurement of the inner surface profile of a straight pipe by using multi-wavelength digital holography has been proposed. To illuminate the inner wall of the straight pipe, a cone-shaped mirror(CSM) is inserted in the pipe and the reflected light from the mirror becomes the object wave and is recorded as phase shifted hologram. When the center of the CSM deviates and/or inclines from the pipe axis, the asymmetric distribution of optical path length around the mirror center is superimposed to the net profile of the pipe inner surface and that causes a crucial error for the inspection. To correct the error, we have proposed the correction method in which both the deviation and the inclination the CSM was taken into account. In this paper, we propose the new automatic error correction method in which the evaluation of the mirror center in the reconstructed image has been improved. We have also performed the experimental verification for the proposed method by using a ring gauge with an inner diameter of 13.97 mm.

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For use as a drive motor in a high precision NC machine tool feed axis, a permanent magnetic synchronous motor (PMSM) requires a highly responsive current control loop. Without consideration of the PMSM electromagnetic characteristics such as voltage saturation and magnetic saturation, the current control loop may be unstable. This paper proposes a method for determination of the PMSM current control parameters providing such high response, while avoiding voltage saturation by inverter output voltage constraint or declination of inductance by magnetic saturation. Experiments were done using two representative PMSMs alone and also using a machine tool. Testing confirmed that the proposed method is effective for achieving a highly responsive current control loop and making the cutting surface smoother.

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