[in Japanese]

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Surface-roughness can be seen on many types of materials by using special microscopes or can be quantitatively measured with various optical and mechanical profilers. There are instruments that measure total integrated scattering and angle-resolved scattering and then appropriate theories can be used to relate these measured values to surface roughness. Roughnesses that can be measured have heights that range from less than atomic distances to many microns. Surface spatial wavelengths, i.e., the spacing between roughness height features, are also important.

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This study aims at clarifying the relationship between the surface integrity of PTFE finished by an ultra-precision diamond cutting and the adhesion strength of a metal thin film. As.the first step of this study, the basic properties such as surface integrity in the diamond cutting of PTFE and the effect of the surface roughness on the textile water repellency are demonstrated in this report. The following remarks were found. The measured roughness of finished surface largely exceeded the theoretical roughness, while the cutting force was very small comparing with aluminum and the flow type chips were formed. The surface with a smaller roughness tended to repel water.

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A very small depth of cut has achieved the crack-free removal of brittle materials, known as ductile mode machining. Because a ball end mill has complex shape of cutting edge, cutting situations vary widely according to the change of tool-workpiece interference region. It hasn't been, clarified how the change of cutting situations of a ball end mill affects brittle-ductile transition. This report investigates inclination and tilt of a micro ball end mill affects to the brittle-ductile transition in machining of the borosilicate glass. As a result, it is found that inclination and tilt of a micro ball end mill have a significant effect on the brittle-ductile transition. Deep depth of cut with good finished surface by ductile mode cutting is obtained using a ball end mill vertically to the workpiece surface at a tool feed rate 0.078mm/s.

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A finite element analysis of end milling a nickel-base superalloy is presented for aiming at understanding its cutting performances, and improving cutting conditions, cutting efficiency and machined surface integrity. A formulation coupled with radial return method for thermo-elastic plastic finite element method, penalty methods, mass scaling, subcycling gave chip formation and cuttig processes of Inconel718. Calculated and experimental results on. end milling of S45C with HSS tool agreed well in cutting forces and shapes of chip. From calculated results on end milling of Inconel718, it was found that cutting speed had a great influence on the cutting temperature on the rake face.

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Surface roughness and the dimensional accuracy have been focused as a research object in these days, but surface hardness and residual stress induced within the machined surface layer by the machining process should be another important topic if we want to add some valuable feature to machined surface. In this study, the test cutting conditions were arranged by using the experimental design, and the mechanical properties on machined surface are correlated with the cutting conditions by using the response surface methodology. Then, it becomes possible to. predict the mechanical properties on the machined surface from that relationship. Also we proposed the simulator which can predict the mechanical property of the machined surface against the input of NC program.

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This paper deals with the cutting force monitoring for intelligent end milling operations. A monitoring method, which utilizes sensitive displacement sensors, is discussed. The sensors are installed in X Y directions near the front bearings of the spindle, to detect the small displacements of a spindle caused by cutting forces. Cutting forces are estimated from the displacement signals by the simple signal processing technique. Impact hammering tests and cutting tests are conducted to validate the monitoring method. The test results show that the dynamic force can be estimated from the signals of the displacement sensors.

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This paper proposes a new centerless grinding technique using surface grinder. It is a technique that centerless grinding operations are performed in low cost by installing a compact centerless grinding unit consisting mainly of an ultrasonic elliptic-vibration shoe, a blade, and their respective holders on the worktable of a multipurpose surface grinder without the employment of a costly centerless grinder. The function of the shoe is to hold the cylindrical workpiece together with the blade, and to control the workpiece rotational speed with the elliptic motion on its end face during grinding. In this report, the design and manufacture of a centerless grinding unit, and several grinding operations on the produced unit using a surface grinder are described.

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Recent machine tools have been required both high-efficient and high-precision machining. The increase of a calorific amount due to the speed-ups of the rotational speed and the feed rate becomes one of the major cause of the machine tools' thermal deformation. The authors have proposed an efficient reduction method for the machine tools' thermal deformation. This method is aimed to collect and remove the heat, which have generated inside the machine tools, before it is spread over the adjacent components. For the basis of establishing the method to.reduce the thermal deformation, this report indicates the experimental results of the insulation effects of an insulator being sandwiched between the contact surfaces and clarifies the effects of both material and thickness of the insulator and the contact surface pressure on the thermal contact resistance. The experimental results show that the thermal contact resistance of CFRP with 1mm in the thickness was about 10 times as much as the resistance of the direct contact.

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This paper deals with the PCD ball nose end mills were manufactured by a CNC tool grinding machine with EDM function. The EDM function of this machine was determined to use for machining the large amount of rough portion of PCD in order to reduce final grinding operation using diamond-wheel and to make the cycle-time shorter. On the other hand, In order to minimize damage to the cutting edge of the EDM process on PCD, it is necessary to be able to simply produce a higher peaks of minute electrical current. That is why the power supply using the condenser circuit method is practical, as it is relatively inexpensive.

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This report deals with a precision machining of harden stainless steel by use of a cBN micro milling tool. A cBN micro milling tool with 8 cutters was .developed. In this study, a basic cutting characteristics were researched and aspherical harden stainless steel was tested. From the experimental results, it was clarified that cBN micro milling tool was useful for ultra precision cutting of aspherical harden stainless steel.

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In the present research, a ultra-precision diamond cutting of thermo-plastic materials, polycarbonate (PC) and cyclic olefin polymer (ZEONIX), is carried out by applying a method named ultrasonic elliptical vibration cutting developed by the authors. It is experimentally proved that good-optical surfaces are obtained by applying the elliptical vibration cutting in cases of machining of symmetrical and dissymmetrical V grooves as compared with the conventional diamond cutting. The surface roughness of dissymmetrical V grooves obtained by the ultrasonic elliptical vibration cutting is 10 nmRz and 41 nmRz for PC and ZEONEX, respectively.

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Single-crystal InP is a new compound semiconductor material. In the present work, diamond turning experiments on InP (100) were conducted to examine its machining characteristics. The surface texture was found to change significantly with workpiece crystal orientations. Three kinds of surface textures were observed during the brittle-ductile transition of machining mode. The critical undeformed chip thickness at which completely ductile-cut surfaces were obtained on all orientations was approximately 20〜50 nm. A smooth surface of 26 nmRy was obtained with generating continuous ductile chips. These results provide feasibility for high-efficiency fabrication of InP substrates by diamond turning.

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Vacuum chucks are usually used in ultra-precision turning of thin plates like magnetic aluminum discs, for which high machining accuracy is absolutely important. Especially, high form accuracy of machined discs can be expected of porous vacuum chucks because they are superior on uniformity of supporting rigidity to other types of vacuum chucks. Consequently, final purpose of this study is to develop a new porous vacuum chuck suitable for ultra-precision turning of thin plates. As a first step, the new porous vacuum chuck was designed with reference to previous studies, and was made on an experimental basis. Furthermore, important functions of porous sintered fluororesin adopted as holder material were investigated. As a result, it was demonstrated that the chuck made from porous sintered fluororesin had holding forces enough to machine discs and deformation of discs when mounting them could be smaller than other chuck made from the porous sintered ceramics or metals because modulus of elasticity of porous sintered fluororesin is fairly smaller than the other porous materials.

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Study on attempts to develop novel fine fabrication processes combined with ELID is being conducted. In this paper, examples on novel combined/ hybrid processing for high-quality and micro-level fabrication are introduced, and a new finishing method called magnetorheological finishing (MRF) of ELID grinding surface is introduced.

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To achieve the manufacturing of disks of the accelerator structure for the high gradient field, KEK develops to manufacture high precision disks. In manufacturing high precision disks, it is important for us to make sure the process sheet of the disk and report actual evidence. By this study we report how to manufacture the disks and the criteria of disk.

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Electron element develops into high speed, high performance and high function, caused by the rapid development of the information technology. As that representative, the wafer becomes a big diameter, and moreover high precision, high quality and a low cost are demanded. It is difficult by the lapping of slurry to satisfy those requirements. A demand for the ultra-precision processing by grinding has been rising. We developed the fine diamond grains wheel of the new concept to process Ultra-precision grinding. Therefore, it is reported about the Ultra-precision grinding that high precision is realized.

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This paper deals with the separation of Pt/C multilayer from an electroless nickel mandrel for making replicated hard X-ray telescope mirrors. There is no example of this technology in the world, though the separation of Pt/C multilayer from glass cylinders can be successfully operated. Using an intermediate layer between the electroless Ni mandrel and Pt layer, the separation has succeeded. The surface roughness of 0.12nm Ra was obtained on replicated Pt/C multilayer surface, which was left from the polished electroless Ni plate of 0.11 nm Ra in surface roughness. Conical Pt/C multilayer X-ray mirrors can be obtained using Ti thin layer as an intermediate layer.

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We have developed a new system to perform the outline measurement of micro parts. The system consists of a laser prove 3D measuring equipment and a rotation table and astitching software. It can measures the diameter and the outline of small parts of it diameter is less than lmm and a high NA aspherical lens of it has an angle over 60 degrees.

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In order to facilitate the advancement of micro machine technology and to encourage its use across a wider range of industrial fields, measuring technology appears to be essential To this end, we have developed a small three dimensional form measuring apparatus which has non-contact probe detecting proximity to measuring object through tunneling effect. In this study, we have introduced dual servo control system to realize a high resolution and wide measuring range in sur&ce roughness measurement of micro-components on the inkro-3D-CMM.

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This paper presents a compact and high-sensitive angle sensor suitable for measurement of stage angular motions, such as pitching and yawing. The compact angle sensor is based on laser autocollimation for angle detection. To maintain the high sensitivity while miniaturizing the sensor size, the relationship between the spot size on the focal plane of the objective lens and the output of the photodetector with separate elements (bi-cell PD and quadrant PD) is analyzed with wave optics. A compact sensor is also developed based on the analysis result. Experiments have shown that the compact sensor has a resolution of 0.01 arc-seconds.

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In general, the dearanoe of the die and punch has a profttund effect on the propeities of shearing work However, optimum dearanoe for metal thin sheets has not been made dear. The purpose of this study is to propose optimum dearanoe in micro punch press. The dearanoe between the die and pundi is precisely measured by image processing using a microscope. In this report a new measuring tedmique for the dearanoe between the die and pundi using image processing system is described in detail Then the validity of the measuring system is shown by results from experiments.

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Three degree-of-freedom (D.O.F.) planar motion stages for precision positioning have a problem that the motion in one-direction will interfere with those in other directions as a disturbance because of the free stage structure. A conventional PID controller does not have the function of compensateing for the disturbance of interference. A disturbance observer is thus employed in the PID controller so that the planar motion stage system becomes more.robustness to the interference disturbance. A feed forward function is also adopted in the controller for improvement of the tracking capability. The detail of the controller design is decribed in the paper. Experiments are also carried out for confirming the feasibility of the developed controller.

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This paper reports a novel method for high throughput analyzing of DNA microarray by using micro grid irradiation that is generated from LCD. The novelty lies in the capacity for fluorescence polarization measurement which enables more than 12,000 spot detection in a few seconds. The LCD matrix could control each irradiation spot respectively. The advantages of this method-are following; 1) non-scan irradiation procedure for high speed measurement, 2) high sensitive measurement by reducing cross-talk noise on neighboring spot. The experimental results shows that the feasibility of controlling grid irradiation, and simultaneous multispot fluorescent deteciton for DNA microarray analysis.

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High air tightness and little plastic deformation are required for the bonding surface of 1,000,000 accelerator disks that:compose the next generation high-energy linear collider. In this paper, the optimal diamond turning conditions are discussed to fabricated such disks efficiently. The leak tests were carried out using OFHC copper disks machined under various conditions and the vacuum level of disks was measured. The surface topography of disks also was measured and the amount of the plastic deformation was calculated from the plastic flow pressure of the copper. The optimal diamond turning conditions are derived by using concept of information amount in consideration of the vacuum level, the amount of the plastic deformation and the material removal rate.

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Depth-sensing indentation system was used to measure the residual stress in the engineered surface of stainless steel. Different with other measurement methods, such as X-ray diffraction_techniques, depthsensing indentation provides a way of accurately measuring residual stresses even with unknown material properties. Comparing the load-depth curves of residual stress existing and stress-free samples, the closed form of expression correlating the level of residual stress with load and depth shifts in the load-depth curves is given. Based on theoretical analysis, a new experimental scheme for determination of the residual stress by indentation is suggested.

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This paper reports an active air linear guide that utilizes air films generated by ultrasonic oscillation. The films on eight bearing surfaces of a horn, which is a stator, lift and guide the carriage. Moreover, the oscillation that modulates the amplitude via the positioning signal varies the thickness of the air film. Thus, this bearing regulates the position of the carriage in z direction using a PI controller with a displacement sensor so that its motion error becomes zero. Furthermore, no pneumatic plant is needed in this bearing. The motion error were 1.28 μm p-p in z direction and 1.08 μm p-p in y direction without compensation. Nonrepetitive motion errors were 0.125 μm 2o in z direction and 0.048 μm 2σ in y direction. PI feedback control, in which a fiber optic displacement sensor measures the movement of a gauge block mounted on the carriage, was performed. The settling time for 0.2-μm step positioning was less than 0.1 seconds. The positioning resolution was less than 20 nm.

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The air slider is used as a guide element for the semiconductor exposure devices. When the positioning of the table attached to the slider is fixed, mechanical clamper such as solenoid is used and exerts a high clamping force on the slider table. However, the high clamping force causes the table to be moved in micrometer order. Therefore, the development of an excellent clamping mechanism with low clamping force and the high response is hoped for. In this study, a new functional material (ER gel) is developed which can generate a variable clamping force in response to an electric field, and applied to the clamping mechanism of the air slider. As the result, the developed ERG clamper is more effective than the conventional mechanical one.

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This paper describes a design and performance of a capacitive position sensing in the axial direction of a one-axis-controlled magnetic bearing, which requires in-process displacement measurement and position control of a spindle. The rotor position is measured using a differential variation of capacitance between the rotor and stator. The measurement method is based on the Abbe's principle. A magnetic bearing structure for -the capacitive position sensing is proposed and designed. Experimental results show that resolution of the capacitive position sensing is a micrometer in 10 kHz bandwidth and 20 μm range.

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There is a demand for an ultra precision machine in a variety of fields such as optical instruments and electronic devices. A precision aerostatic spindle having an axial positioning function is proposed for the ultra precision and compact machine. The spindle has two radial,air bearings that work not only high-precision radial ones but also a linear guideway in the axial direction. The spindle has 15rim positioning resolution at 7,000rpm in the axial direction. This paper deals with an .experimental study of precision milling of oxygen-free copper with a single crystal diamond tool. The height and surface roughness of machined steps are 200nm and 40nmRa, respectively.

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In recent years, there are increasing demands of cell manipulation in fields of bioengineering. However, the current mieromanipulation systems are mainly manual or semiautomatic, which unfulfilled the bioengineering requirements. In this research, a vision con trol scheme has been proposed and developed to identify the targets/tools and pro vide error free information for position and path control.

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We developed a high-speed vision robot system that can be applied to various types of products. The developed system consists of a robot with cameras and lights, and a computer for teaching and image processing. In the system many points on any faces of the product can be inspected without stopping with the help of the developed robot path planning and the synchronous method between robot path and image input. Moreover, we developed standard inspection algorithm and unified environment for robot and vision teaching. Therefore the teaching operation can be done without programming. This system is currently in use in our plants so that it can be helpful in keeping high quality of products.

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There are some guide mechanism of feed drive system of machine tools such as friction slide guideway, ball or roller guideway. And there are some position control systems such as rotary encoder feedback or linear encoder feedback. In both mechanisms and systems hybrid systems exist. In this report, their characteristics are considered in the point of view of motion accuracy.

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To improve the positioning accuracy of a parallel kinematic machine tool, the calibration of kinematic parmeters is needed. A method to calibrate kinematic parameters with DBB(Double Ball Bar) measurements was proposed. However, this method does not calibrate kinematic parameters defined with respect to the location of a table of the machine, and thus the manual rotation of thecalibrated coordinate is needed. Therefore, this method takes longer and it is required to be shortened. This paper presents a new method of calibration with a specialized jig that consists of a ball plate with 7 balls and stoppers to the table. With this jig, the modification of calibrated coordinates is not needed, and the time for the calibration is shortened.

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Recent innovation of the manufacturing technology of linear encoder enabled the realization of long absolute linear encoder longer than 4m. New developed 2 track absolute detection method is based on tip on board technology with image sensor. The image sensors are used to detect 18hit absolute code track and incremental track signal by new single field method. Thanks of this generated excellent analog incremental sinusoidal signal high interpolation was allowed to gibe 10nm final resolution. This over 4 m length absolute linear encoder will be expected more application adapted in electronics market with linear motor.

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In end-milling process, minimal quantity lubrication cutting exhibits friction reduction in some extent in comparison with flood emulsion cutting. However it is not completely clear how the minimal amount of lubricant reduces the friction between a tool and work. In this study, the friction force variations between a tool and work in the intermittent cutting are investigated in detail. Boundary lubrication performance is very significant for the MQL oil because the MQL oil directly lubricates on rake face similar to flood lubrication.

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Environment problems are getting much more attention than ever these days, and we are working on developing dry machining technology which requires MQL or no cutting fluid includes toxic pollutant such as chlorine. We would present newly developed MQL cutting process. After evaluating cutting performance of absolute dry cutting, dry cutting with air-cooling, and MQL cutting, we chose MQL cutting which was found to be superior in terms of the main issues, lubrication and cooling. And then, we developed new MQL cutting by adopting newly developed high lubrication cutting fluid and incidental facilities to secure same cutting tool life and cutting accuracy as those of conventional wet cutting.

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In late years, the exclusion of chlorine and PRTR regulated compounds are demanded for cutting fluid to consider environment. In addition, to prevent a fire, replacing non-soluble cutting fluid with water-soluble cutting fluid is demanded. Furthermore, for productivity improvement, extension of tool life and improvement of processing precision are demanded. In this report, we discuss the effect on cooling characteristic for tool life and processing precision for new water-soluble cutting fluids satisfying these demands.

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MQL (Minimal Quantity Lubrication) cutting uses much less cutting fluids than conventional cutting which utilizes flood supply of cutting fluids. Hence, MQL cutting is environmentally friendly and getting increasing attention. However, tribological mechanism of MQL cutting is unknown. So less understanding Tribological mechanism during MQL cutting was investigated in this paper. To understand this, it is necessary to know how any gases behave near cutting point while cutting, and which gas is effective to cutting performance. Next, it is necessary to understand how lubricant works. To achieve these, purposes, two experimental setups are made. By using these experimental setups, it can be concluded that oxide film is, good lubrication film and it can be guessed that lubricants work on oxide film.

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