For brittle materials, there is a critical depth of cut between ductile mode and brittle mode. However, the critical depth of cut is very small. In order to increase the critical depth of cut, ductile mode cutting of single crystal silicon was realized using ultrasonic vibration. The ultrasonic vibration of 27kHz was applied to a diamond tool in the cutting direction. In the case of conventional cutting without ultrasonic vibration, the critical depth of cut was 0.15μm. On the other hand, in the case of ultrasonic vibration cutting, the critical depth of cut was increased to 8.5μm. The mechanism of material removal in the ultrasonic vibration cutting of single crystal silicon was also discussed.

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This paper deals with development of an extremely high frequency ultrasonic transducer of magneto-striction type with vibration frequency of up to 400kHz and its application to ultrasonic grinding. The developed transducer provides longitudinal, torsional and complex vibration modes. When the transducer is applied to boring for ferrite and alumina ceramic workpieces, grinding force becomes stable and chipping is reduced, especially in the complex mode vibration.

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Pneumatic vibration table was originally developped to improve defect for forming segmentalized chips of small hole drilling. The pneumatic vibration table is also utilized for grinding process, and chip conveying owing to its simple structure and small sizing. This paper describes applications of pneumatic vibration for mechanical processing

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As one of the core technologies of the one-stop grinding machine forφ300mm silicon wafer manufacturing, a precision positioner using Giant Magnetostrictive Material (GMM) has been successfully developed to control infeed and posture of the grinding head. With the closed-loop feedback control, the actuator is able to move half a ton of payload at the resolution of 6.25Å. The first trail test has shown the result of surface roughness Ra less than 1nm and global flatness less than 0.2μm.

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A machining system of diamond turning based on the fast tool servo technique has been constructed for generating micro-patterns. To accurately generate the micro-pattern and understand the nano-cutting phenomenon, it is desired to monitor the machining force in the machining process. In this paper, an instrument was designed and fabricated to moni-tor the machining forces during diamond turning of the micro-pattern. Instrument design and measurement results are presented.

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Si (100) surface anisotropy etched in aqueous KOH exhibits the fractal characteristics. But the formation mechanism of the fractal structure of etched surface has not been made clear. Therefore, the simulation of the surface growth was carried out using Monte Carlo method, and the results were compared with the experimental data. The simulation demonstrated that the artificial surface roughness was similar to the etched Si surface roughness in its time, concentration and temperature-dependent fluctuations. This proves that the Si surface showing self-affine characteristics is formed by the selective dissolution of Si atoms and the selective stick of micro masks.

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In this article, we report on the length and angle measurement methods using a regular crystalline lattice as the reference and a scanning tunneling microscope (STM) as a detector. (1) An absolute length measurement method with mm order range and sub-nm accuracy by combining a regular crystalline lattice and a laser interferometer is proposed, Optical fringe nλ(n : integer, λ : laser wavelength), which is determined with pm order accuracy by the interferometer, is used as a coarse scale. Lattice spacing on highly oriented pyrolytic graphite (HOPG) crystalline surface (∿0.25nm) is utilized as a fine scale. (2) A unit-angle measurement with nanoradian resolution by referring atomic structure (=crystalline axes) on crystalline surface is proposed. A design and operation method of a unit-angle measurement machine using the HOPG crystalline surface and the STM is discussed.

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We have been developing the new probe technique for the nano-CMM, that is called the laser trapping probe whose principle is based on single-beam gradient-force optical trapping techniques and microscope interferometers. The work reported in this paper deals with fundamental characteristics on the practical positional detection and measurements of a glass microsphere with National Institute of Standards and Technology (NIST) traceable mean diameter of 168±8.4μm using the laser trapping probe based on Linnik interferometer. Positional detection is based on displacement of a microprobe sphere caused by external forces at the position where it approximates to a workpiece. Linnik interferometer performs sensing this displacement with high accuracy. Measurement results of the glass micro-sphere demonstrate a potentiality of the laser trapping probe as a positional detection probe for the nano-CMM.

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This paper describes surface interpolation method using spline function and definitions of 3D surface parameters. A surface which can be differentiated mathematically is made by interpolating a discrete and quantized measurement data. B-spline is used in the interpolation. The 3D surface parameters, slope parameter and local peak, are calculated uniquely by mathematical and computational way. The presented method has advantages of current surrounding 4 point method or 8 point one. The spline interpolation can be linked to the spline filter, then the presented evaluation scheme is general and systematic.

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These days Aspheric Lens is much used in a variety of areas such as Visual, Information and Medical Instruments et al., and it is getting more complex and high accurate. This paper describes Ultrahigh Accurate Measurement Technology supporting development and production of Aspheric Lens and application of this technology in measurement of Wafer for next generation mass-storage semiconductor.

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This paper describes a high-precision coordinate measurement machine, which we call "A-Ruler." It will be used to measure the shape of freely curved surfaces with an accuracy of 5nmRMS at a measurement volume of 350×80×50mm^3. Studies on margin of error indicate that the measurement of a spherical surface is influenced by almost all types of errors. This indicates taht the performance of A-Ruler can be assessed by measuring a spherical surface. The influences of scanning velocity and the sphericity of the tip-sphere are also investigated using a concave sphere workpiece made of Zerodur^<TM>. Its curvature radius is 104.508mm. The repeatability is 3.8nmRMS perφ120mm area. The accuracy is assessed by comparison with an interferometer. The difference between A-Ruler and the interferometer is 4.5nmRMS perφ120mm area.

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This paper describes the machinability evaluated by mechanical strength of workpiece when wire electrical discharge machining, cutting, grinding and polishing of titanium aluminide intermetallic compounds. The results obtained from this study are as follows : Surface defects and edge breakouts are formed along the layer direction of lamellar structure. Bending tests whose specimen are machined by the four methods are conducted. Grinding and polishing specimens have superior strength to cutting and wire electrical discharge machining specimens. In the case of lower strength specimens, the breakouts or crackes are observed at edge. It is proved that the strengths are related to formation mechanisms of surface and edge defects correlated with machining method.

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In industry there are many ring-type machine parts such as the inner and outer lace of bearing, the inner diameter (ID) and outer diameter (OD) of which need to be ground precisely. Usually in order to grind these parts two grinding processes are necessary. One is for OD grinding using a cylindrical grinder, and another is for ID grinding using an external grinder. Thus for reducing process cost and improving machining accuracy the simultaneous-ID/OD combination centerless grinding is expected to be suitable. However the ID and OD rounding mechanism in this process are very complicated because of its complicated geometrical arrangement. In order to investigate the ID/OD rounding action, a computer simulation method is developed in this work. This paper deals with the development of simulation method and reports some simulation results.

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This report deals with the possibility of ductile mode grinding of optical glass BK7 by means of the metal bond diamond wheel with #140 coarse grain seize. Although the grinding modes such as ductile, ductile & fracture, and fracture modes are affected by the depth of cut, table speed, and grinding speed e.t.c, measuring the topography of working wheel surface just after the dressing is a key factor performing ductile mode grinding of BK7. The detailed observation of the behavior of cutting edges and the cutting edge distribution was examined under various grinding conditions using the newly constructed equipment. As the result, the optical surface in surface roughness was 43nm rms, 207nm Ry in ductile mode grinding.

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In this study, a new technique of in-process characterization of the grinding wheel surface is proposed. Some reference topographies of the wheel surface are formed by different dressing conditions. and the condition of the wheel surface is discriminated where the dynamic fre-quency spectrum signals of grinding sound and/or vibration are analyzed by a neural network technique. In the case of conventional vitrified-bonded alumina wheel, both grinding sound and vibration can be identified under the optimum network configuration in such that learning rate is 0.003 and number of hidden layer is 160. Accordingly this system can recognize the differ-ence of the wheel surface in a good degree of accuracy insofar as the micro-topography of abrasive grains are relatively widely changed.

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The IT industry prospers with the development of the electric technique. The electric technique stands up in the high quality of the electronic part. The part manufacture is looking for the high precision and the low cost. New vitrified bond Wheel meets those requests. The good point can do low Grinding force and do continuation grinding in fine abrasive. In this paper, it introduces the grinding case of the silicon. Moreover, it reports the optimal design guide of the wheel.

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Abrasive jet machinig which is typically blasting is rough working as deburring and rough finishing. But otherwise it has been increasing that the materials used for semicondector, electronic devices and LCD parts are worked by micro abrasive jet machining, because it is a method of dry manufacturing and high productibity. According to their requests we have developed the micro abrasive jet machining equipment which is a blasting equipment used micro abrasives and is able to work hard and brittle materials for uses of uses of semiconductor, electronic devices and LCD parts in high accuracy. The micro abrasive jet machining equipment which is called MICROBLASTER has an abrasive feeder which is able to supply micro abrasives constantly. We introduce an outline of this equipment and machining characteristics of hard and brittle materials for microblasting technology in this report.

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In the case of the internal finishing of a bent tube by a magnetic abrasive finishing process, the magnetic field, therefore the finishing force, is non-uniform in all finishing areas due to the geometry. This affects the abrasive behavior against the inner surface of the bent tube, changing the finishing characteristics. This paper discusses the effects of the orientation and position of the magnetic poles with respect to the bent tube on the magnetic field, the abrasive behavior, and the finishing characteristics at the bent section. The finishing experiments of elbows indicate that the non-uniformity of the finishing characteristics at the bent section can be diminished by offsetting the axis of the poles' rotation from the elbow axis.

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Polishing of brittle material such as silicon wafer and glass disc has been conducted by using vesicant polyurethane pad which has worn with polishing of a workpiece. Polishing characteristics of a glass disc are influenced by a wear mode of the pad. Present paper focuses on finding of the relationship between wear of the pad and its visco-elastic property. Volume fraction wear of the pad is estimated with an optical microscopy and also visco-elastic property of the pad is measured with a balancing type measuring setup. It is found that the pad has gradually worn with polishing process, in which wear rate of the pad is dependent upon its visco-elastic property. Experimental data show that there is some relationship between wear mode of the pad and visco-elastic property of it. Finishing characteristics of the glass disc is closely related to wear mode of the pad.

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The aim of this study is smoothing the diamond film with high efficiency and low damage. The diamond film was polished with using glass materials and high speed polishing machine. In the process, pressure, revolution speed and slurry density were changed. After polishing, processing characteristics were examined the diamond film surface were evaluated.

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Structured surfaces create various functions such as optical filters, anti-friction and so on. Recent progress in various technologies expands the application area of such functions rapidly. This paper describes the survey on the current status and future trends in the functions achieved by processing the surface in abroad. The items about manufacturing processes and the metrology are also mentioned as well as the description of examples of various applications.

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Technology trend in some kinds of displays of LCD, TFT, FED, OELD, PDP and so on are reviewed. Some surface functions of alignment, polarization, infraction, electron radiation, and so on are demanded for these displays, and there are many tasks on production technologies for them. The overview for these tasks is shown also.

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Recently micro tribology has been recognized its important role. In particular micro dimples in a piston of an engine are known well. This paper describes periodic structures which will be adopeted into micro tribology fields. Two methods which produce micro periodic structures are introduced. They are powder beam method and laser beam method.

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Fabrication methods of micro grooves are investigated. Two types of processing methods are developed. One is laser-assisted etching, and the other is mechanical processing using a burnishing tool. In laser-assisted etching, the spiral grooves were formed on a 0.5-mm-diameter shaft. This method successfully formed grooves 8μm in width and 2μm in depth on the surface of a shaft. Next, in the burnishing method, effects of grooving conditions upon groove geometry were studied. The profiles of micro grooves less than 1μm m in depth were compared with the geometry of a diamond tool. Texture pattern with micro grooves was formed using the burnishing method.

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In the manufacturing technology and design of vacuum apparatus, the next two items on its surface function have been the subjects to be solved for a long time ; (1) Prevention of air leakage, (2) Decrease of out-gas. Practically, their phenomena have now become to understand pretty well, thanks to not noly basic researches but also a lot of information, knowledge and know-how accumulated on the way of progress and development of this technology. However, we must admit the fact that viewpoints for this phenomena, which is micro-scopically induced by atomic or molecular behavior, are separated into the two extremes : i.e., a scientific viewpoint is academic and a technological viewpoint is practical, and their combination has not discussed sufficiently so far. In this paper, the surface function o nthe gas leakage and the out-gas phenomena were experimentally investigated standing upon the mid point (engineering side) and tried to evaluate their surfaces functions. As a result, some data relating the surface topography for the gas leakage and the out-gas were obtained.

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This paper describes the instrumentation and computational conditions of geo-statistical parameters for engineered surface texture in order to analyze the correlation between surface function and its geometrical characteristics. After explaining the present state and issue of the related instruments on the market, the measuring conditions and calculation procedures are proposed for certain engineered surfaces. It extends to the practical effectiveness of multivariate analysis to combine the surface function together with the geo-statistical parameters.

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In electrical discharge machining (EDM) of die steel, a hard white layer, which is different from the base metal, is formed on the metal mold surfaces caused by rapid heating and cooling. Cracks and micro-craters appear on the surface of the white layer depending on the machining conditions used. Such heat-affected zones (HAZ) can greatly shorten the life of metal molds. In this study, the method of laser surface modification with melting has been proposed as a new surface modification method. This method can eliminate defects, such as cracks and micro-craters, by melting and solidifying HAZ using a laser beam as the heat source. As a result, the laser-irradiated surface, in the absence of an absorbent, is converted into a flat surface with neither cracks nor micro-craters that are generated by EDM. It was found that tensile stress with values ranging from 550MPa to 850MPa is retained in the irradiated surface, and the residual stress can be removed by aging treatment at 580-600℃.

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