There is increasing demand for micro-lens molds. A desktop machine tool for machining of micro-lens molds is required. However, when a grinding wheel with a small diameter is used, the ELID grinding method experiences problems related to installation of the negative electrode. In this study, for the purpose of machining of a micro-lens mold, we developed a system to realize electrolysis using a small type ELID grinding wheel that did not require use of the negative electrode. The results indicated the successful development of an ion shot dressing grinding system that uses a nozzle type electrode. The use of a #4,000 wheel produced a finished roughness of Ra 1.5 nm, with good form accuracy of P-V 0.8μm.

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The fundamental characteristics of the natural diamond milling process were investigated using 30 keV Focused Ion Beams. The processing yield of milling diamond with normal incidence was 0.08μm³/nC. There was no difference in yield between the diamond crystal orientations (100), (110), and (111). The dependence of yield on the incident angle was also measured. The maximum yield was observed at an incidence of 87°, and was sixfold greater than the value at normal incidence. When the H₂O-assisted etching process was used, the yield increased by fourfold, and the roughness of the processed surface was smoother in comparison to the process without the gas assist. The practical processing rate was estimated to be 0.14–1.1 m³/s at a beam current of 1.6–17 nA without gas assist.

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A high-precision milling process of natural diamond was developed using Focused Ion Beam (FIB) technology. The FIB diameter determines the limitation of the 3-dimensional milling process edge sharpness. This report presents a comparison between the beam diameter obtained by actual measurement using the frame scan edge shape and the theoretical calculation values. In addition, an AFM cantilever with diamond probe (DCL) was developed by transplanting diamond to the cantilever after pre-processing the small diamond selected from abrasive powder. This DLC enables repair of chrome residue of advanced photomasks with excellent performance applicable for practical use. This new method can produce a probe shape such as a 20°tip, overhang tip, etc., which are difficult to make by mechanical polishing. In addition, as it is lightweight, the DLC has a high resonance frequency (fc).

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A ball-end mill is generally used for cutting of curved surfaces. As the contact point between the ball-end mill and the workpiece depends on the normal direction of the cutting point and each cutting point of the cutting edge has different cutting conditions in ball-end milling, it is difficult to predict tool wear due to the complexity of wear form. Here, ball-end mill tool wear distributions were examined and the characteristics of tool wear progress are explained to derive a tool wear prediction equation based on the tool wear characteristics. A system to estimate tool wear distribution of a ball-end mill based on the tool wear estimation equation, defined with the real cutting length and cutting conditions at each cutting point, was developed. The usefulness of the system was confirmed by experiment.

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Burrs are formed at the edges of machined workpieces in most metal cutting processes. These burrs cause problems in production lines in terms of added cost and time required for a deburring process. The purpose of this study is to investigate the influence of workpiece hardening on burr formation in face milling of carbon steel JIS S45C. Before machining, laser hardening using a CO₂ laser is conducted on the side face along the line where burrs formation is expected. The laser-irradiated area of carbon steel has high hardness and brittle characteristics in comparison with the mother phase. When machining laser-hardened workpieces, the burr height is smaller compared with standard steel. By controlling laser irradiation conditions, burrs are not observed, and chipping (negative burr)-like chamfering occurs. Even when burrs are formed before finish cutting, only laser heat treatment along the last depth of the cut line could prevent burr formation. The surface roughness is hardly influenced by laser heat treatment. These results indicated that laser hardening is effective to prevent burr formation, and this technique will be applicable to high efficiency processing.

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The removal properties of lamination on multilayer LSI using an AFM mechanism with machining cantilever with two types of flexural rigidity were investigated to determine the depth of removal, wear of diamond tips on the machining cantilever, and scratched surface of the multilayer LSI using a diamond tip on the machining cantilever under several scratching conditions. The results indicated that it was difficult to obtain good surface integrity on the multilayer LSI, favorable wear resistance of the diamond tip and sufficient depth of scratching using a machining cantilever with low flexural rigidity. On the other hand, when a machining cantilever with high flexural rigidity was used, the wear of the diamond tip was increased. However, the maximum depth of scratching on multilayer LSI reached more than 3 ?m. Therefore, each wiring layer in LSI controls the scratching load on the machining cantilever.

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