This paper deals with the machinability of BN Added Steels in turning with several cutting tools. The highest Al content TiAlN coated carbide tool showed smaller flank wear and crater depth than those of the other TiAlN, TiC, TiN and TiCN coated carbide tools. It shows that these tool wears depend on the affinity between tool surface and adhered layer including AlN. The wear of the alumina ceramic tool in turning BN added steel was smaller than that in turning standard steel. However the wears in turning low Al content BN added steel and high Al content carbon steel were almost the same as that in turning standard steel. It shows that appropriate Al and BN in work material are necessary to obtain the longer tool life. The wears of the TiC added alumina ceramic tool and the CBN tool in turning BN added steel were also smaller than those in turning standard steel.

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A multilevel computer generated hologram (CGH) was made on a parabolic copper mirror for laser beam shaping. The CGH consisting of eight height-levels with 0.94μm in step height has been fabricated with a laser-beam direct writing lithography and the mask-electroplating method. The CGH was designed for laser surface modification with a high-power CO₂ laser. The Gaussian distribution of an incident laser beam was shaped into a Rectangle-Gaussian distribution on a focus plane of the parabolic mirror. The diffraction efficiency was 68%. When the shaped laser beam of a 1.5kW CO₂ laser irradiated a steel surface, a uniform melting layer was obtained.

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Deposition of Diamond-Like Carbon (DLC) films at atmospheric pressure is one of promising techniques to achieve in-process coatings regardless work sizes. This research aims at synthesis of DLC films under atmospheric pressure by nanopulse Chemical Vapor Deposition (CVD) method using unique power source system that consists of a static induction (SI) thyristor and an Inductive Energy Storage (IES). In this report, we realized synthesis of DLC films in open air (101 kPa). Deposition rate was as high as 0.4μm/min, and the hardness of the film was 20.6 GPa. From Raman spectroscopic analysis, quality of film significantly depends on input power and deposition time.

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The bending acts on the bolt further with tension and torsion by tightening of the threaded fasteners. The bending moments of the bolt shank caused by the asymmetric shape of the screw threads and the tightening on the inclined bearing surface are examined analytically and experimentally. The value of bending stress within the bolt which produces by the asymmetric shape of the screw threads is very small. However, the maximum value of the bending moment of the bolt shank caused by the tightening on the inclined bearing surface increases proportionally to the angle of inclination. The value of that bending moment is large. The validity of the analyzed result is confirmed by some experiments. Furthermore, it is revealed that the bending moment of the bolt shank influences the torque coefficient for tightening of the threaded fasteners.

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This paper describe precision polishing of the silicon wafer using dilute NaCl electrolytically reduced water, instead of conventional polishing with slurry which is environmental load increase and cost overrun. First, by the comparative experiment about the etching operation of electrolytically reduced water, NaOH solution and pure water to the surface of silicon wafer, it clarified the etching performance of electrolytically reduced water. Next, it experimented in the polish about the wafer which has oxide film (SiO₂) and the wafer which removed oxide film (SiO₂) by HF. It clarified the polishing characteristic of silicon wafer when using electrolytically reduced water by the experimental results. Moreover, when using electrolytically reduced water as polish solution, it clarified relation between the removal rate and polishing condition of the silicon wafer. It proved that electrolytically reduced water didn't have a bad influence on the polish pad last. By the result of this research, it proved that dilute NaCl electrolytically reduced water had an enough performance as the polishing solution of the silicon wafer.

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The development of recent semiconductor industry depends greatly on the innovation of the technology. Silicon chips used as semiconductor element, etc. require higher accuracy. Presently silicon wafers with diameter as large as 300mm are generally used. On the other hand, the improvement in flatness and roughness is required in order to use lapping process in large diameter wafers. Generally, the lapping is performed using a “4 way lapping” system. In 4 way system, several wafers can be lapped simultaneously by rotating and revolving the several wafers and rotating the lapping plate. However, various problems are pointed out when large diameter wafers are lapped in 4 way system. Therefore, the single wafer lapping method which uses the small diameter tool has been discussed, recently. This paper describes the basic characteristics of the oscillation controlled lapping method based on a series of experiment and the computation results. Besides, the consideration of traction expressed by the Preston's equation is used to the computation. Moreover, the method in this paper uses the genetic algorithms for deciding the oscillation controlled conditions. As the results, we can get the good agreement between the theoretically aimed profiles and the experimental results.

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A bio-chemical treatment system was developed to reutilize the spent water-soluble coolant as a diluent of renewal coolant. The bio-chemical treatment using oil-decomposing microorganisms and a biological activated carbon filtration method showed a high recovery rate of water resource from an emulsion-type coolant. The water-soluble coolant can form the uniform micelle colloid in the recovered water and showed no quality change during the nine months standing at ambient temperature. The processing cost, around 35 yen/L, was equal to or less than current disposal cost. No difference was shown in the chisel and flank wear of machine tool after 100 holes drilling between the water-soluble coolants diluted with recovered water and service water. These facts indicated that the proposed treatment system must be an effective way to reutilize the water-soluble coolant as the diluent of renewal coolant.

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The purpose of this study is the realization of the high precision measurement technology (accuracy : 0.01%) of the large diameter lens for ultraviolet rays(wavelength:193nm). Transmittance measurement method with photoacoustic spectroscopy is proposed. This technology depends on only photothermal effect at a local minute area and is independent of lens size. Therefore, this proposed method can be applied to large diameter lens. Further, measurement time at one point is extremely short. So the features of this new method is that the transmittance distribution in-plane can be easily measured in a very short time. Using the small diameter lens, we obtain the equation of the relationship between the absorption coefficient and the amplitude of the photothermal effect by the conventional calorimetric measurement. And, based on this equation, it was experimentally verified that this photoacoustic spectroscopy could be applied to large diameter lens.

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The vibration / noise of gears in production is one of the serious problems for e.g. vehicles and other machines. Characteristics of vibration / noise of gears are strongly influenced by tooth flank form deviation of sub-micron meter order. The quality of product gears is controlled by gear measuring machine and it is calibrated with involute artifact. However, the current calibration method of involute artifact can not achieve enough accuracy and its traceability is not guaranteed. In this report, the method to measure the involute artifact directly by laser interferometer is proposed. Following fundamental experiments are carried out and the influence of surface condition of target object to be measured, and the effect of driving system of artifact are investigated. The difference of measured profile forms is approximately 0.1 μm when the measurement of artifact from tip to root is executed. It is confirmed that the proposed method has a potential to accomplish a highly precise measurement of involute artifact.

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One of the authors has proposed an efficient design method of time-varying gain type controller using the solutions of time-varying Riccati equations (TVREs) and its application to a positioning control problem of a time-invariant vibration system. The responses of this method become similar to the responses of conventional nonstationary optimal regulators (NORs) which are effective controllers for positioning of vibration systems. This method generates the solutions of a TVRE and the responses of a controlled object simultaneously. The time-varying gains are obtained by real-time computations in actual implementations. This feature is convenient for the realization of some adaptive control. This study applies an adaptive nonstationary control method based on the feature of the previous study to the positioning control of a time-varying vibration system whose natural frequency is time-varying. The effectiveness of the method is verified theoretically and experimentally.

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A low-pass filter is applied frequently to finite length data. Because of this finite length data, unexpected vibration which is called an end-effect occurs at the end of data as an output of the low-pass filter. To solve this problem, a spline filter which uses a smoothing spline has been proposed. The smoothing spline is one of the natural spline functions that interpolate given data most smoothly and minimizes a bending energy of its function. By using a natural boundary condition of the natural spline, this paper proposes a natural spline filter that generates no end-effect and is applicable to low-pass filters with different various transmission characteristics. A few experiments demonstrate the effectiveness of the natural spline filter for the reduction of end-effect.

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The distance between corneal vertex and spectacle lens is called vertex distance. It is important to adjust this length in optometry to obtain the right correcting vision when we wear spectacles. In conventional evaluation of vertex distance, the optician measures it from the upper side and horizontal side of the face. Therefore, the measuring accuracy is influenced by the optician's skill. In this study, a new method for measuring vertex distance using three dimensional measurements of the face is proposed and verified by experiments. Experiments of three kinds of lenses such as plane, concave and convex were carried out. The result agreed well with the theoretical value.

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In semiconductor lithography equipment, overlay errors are caused by various factors such as poor adjustment of the equipment, wafer deformation through the process, and environmental unstability of atmospheric pressure and temperature. To explore key factors of overlay errors, this paper proposes a method of performing detailed analysis of overlay error variance. In addition, new analysis method is explained, and an actual example of the analysis is shown.

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The measuring system for particles with diameter of nanometer order sizes on a Si wafer surface using a laser light-scattering method has been developed. To estimate this measuring system, the measurement of a standard particle on a bare Si wafer was attempted and it was verified that this measuring system could measure particle size with a sensitivity of about 24nm. And, the washing for the Si wafer by using a wet cleaning method was attempted to estimate the wet cleaning effect for nanoparticles on its surface. Consequently, it could be verified that the wet cleaning is an effectual method to remove standard nanoparticles of less than diameter of 30nm on Si wafer surface.

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For the users of automatic control valves, leakage of the fluid from the gland packing portion has been a problem as main cause of failure. In this research, the measuring method of the radial pressure of the gland packing, which is directly related to the sealing characteristics, is proposed. The semiconductor pressure transducer is attached to the bonnet, and through the grease filled in the hole in the bonnet, the radial pressure was directly measured. First, the validity of the proposed method was confirmed by comparison of the result to the pressure value expected from the strain of the bonnet. Next, this measuring method was applied to the model system. The radial pressure distribution of the piled packing and its dynamic behavior under conditions the stem was driven was successfully observed. Consequently, the method was shown to be useful to observe the radial pressure distribution, especially in dynamic conditions.

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