Material Removal Rate of sapphire CMP using silica slurry with the fullerenol increase as the higher concentration of the fullerenol in the slurry. The surface roughness of the sapphire substrate gives the influence against the MRR of sapphire CMP. Raman spectra indicate that molecule structure did not change during CMP process. The structure of fine particle by silica particle and fullerenol in the liquid characterize using DLS method. As results, two layers fullerenol molecules are adsorbed on the silica particle. And we discuss on the fine particle with the fullerenol based on our results.

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The effects of conditioning ring groove shape at polishing using conditioning ring type polishing machine have not been fully elucidated. In this research, we aimed at optimizing conditioning ring groove shape and improving polishing performance. In this paper, we carried out the image processing using the transparent polishing machine and investigated the relationship between the pixel value and the concentration of abrasives. Using the above relationship we varied the conditioning ring groove shape and compared the concentration of abrasives between work and surface plate.

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For increasing the integration density of semiconductor devices, there is growing demand for achieving high global flatness and site flatness especially near the wafer edge in polishing of silicon wafers. In this study, polishing conditions in double-sided polishing process were optimized to uniform material removal distribution on wafer and polishing pad properties for decreasing edge roll off were investigated.

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The parameters that the effecting wear mechanism of cBN tools on the hardened steel (SCr420) turning was investigated. In the previous report, it was suggested that wear damage pattern on flank face changed from mechanical damage to thermal damage at above certain cutting speed regardless of cBN content and that the cutting fluid did not effect on flank face. In this paper, the crater wear damage pattern was investigated using scanning electron microscope and confocal laser scanning microscopy. As the result, it was found that cutting speed had an effect on volume of crater wear and the cutting fluid had an influenced on rake face of low cBN content sintered compact.

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The high precision technology for small optical components has been already established in the optical manufacturing fields. On the other hand, in recent year, the high precision geometric shape and surface roughness are required for large glass components molding process. In the comparing of a glass optical component and a metal one such as aluminum, the cost of glass optical component is lower than metal one. In this research, the polishing process of stainless steel molding dies that are used to form thin glass components is investigated. As a result, a stainless steel molding die surface are polished to the surface roughness of below 200 nm(P-V) with 0.5% - alumina polishing liquid. Then, in the case of a polishing process with only own weight of molding die and polishing pressure of 0.5 kPa, those polishing time is approximately 60 hours and 20 hours respectively.

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Machined parts of stainless steels as difficult-to-cut materials are widely used in many industries, which are transportation equipment, electrical machinery, automobile and aerospace industry. This study describes that the characteristics of machined surface by end milling and burnishing process for SUS304 austenitic stainless steel on the machine tools. Moreover, the difference in the influence of cutting conditions such as up-cut and down-cut processes on the machined surface is discussed. As the result of experiments, feed rates in end milling and burnishing process influences the machined surface texture. Hardness of machined SUS304 as workpiece materials is remarkably much higher than hardness of non-machined SUS304 as raw materials. Finished surface of SUS304 has a hardness of 300 HV or higher in terms of Vickers hardness, which is over twice up to three times higher than the hardness of SUS304 raw metals.

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The material adhering to the cutting edge of a cermet insert was evaluated by the profiles of machined surface in turning of SUS304. Height of adhered material depends on shape of chamfer especially in high cutting speed range.

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Inconel 718 is widely used in industry for the sake of its desirable properties. However, it also is typical difficult-to-cut material. To improve its machinability, this study proposed ultrasonic turning by applying elliptical vibration on the base plane. Experiments were conducted on a commercial ultrasonic cutting unit installed onto a commercial NC lathe to investigate the fundamental machining characteristics of Inconel 718. As a result, the cutting forces were found to be lower in the new method than in conventional turning. Furthermore, the flank wear of cutting tool used in conventional turning became heavier; in contrast, less flank wear were found on the cutting tool used in ultrasonic elliptical vibration turning.

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This paper describes micro-drilling processes for printed writing boards (PWBs) containing fillers with high hardness and high thermal conductivity. Inspired primarily by devices such as digital cameras, laptop computers, and wireless communications devices, the electronics field today is continuously demanding smaller, lighter, and more technologically advanced high performance devices. However, that the increase in semiconductor-generated heat tends to affect such devices negatively. Additionally, from the viewpoint of environmental problems, electric vehicles and LEDs are being developed actively. PWBs are one of the principal components for building such devices. In recent years, PWBs containing alumina fillers with high thermal conductivity have been developed and begun to be widely used. However, when processing these PWBs, the drill tools become severely worn because of the filler's high hardness. We therefore examined the drill wear characteristics. The results show the filler is the main factor that causes drill wear, while the increase in cutting force does not affect it. The cutting force increases with the drill wear linearly. Moreover, the characteristic of PWBs with higher filler content rates is close to that of in organic material like ceramics.

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CFRP(Carbon Fiber Reinforced Plastic) is widely used for airplane, automobile and general machinery because of its high specific strength and modulus of elasticity. CFRTP(Carbon Fiber Reinforced Thermo-Plastic) is especially attracting the attention of the viewpoint of recycling and molding speed. In machining of CFRTP, softening of matrix resin causes burrs because of cutting temperature. In this study, side milling tests are carried out by changing cooling condition (Dry/Cryogenic). Liquid nitrogen is used as coolant for cryogenic machining. Cutting force, surface integrity and tool wear are examined. The employment of cryogenic milling effectively suppresses burrs. It is also pointed out that the tool wear is larger than that in dry milling.

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The CFRP pipe that attached a semicircle of ψ2.0mm rib internally was made for trial purposes by using the silicone rubber mold. Strength has increased by increase of the number and the number of rolling of ribs. Bend strength of the pipe without the rib of the commercial item is 42.0MPa, that of the pipe that applies the rib that comes to this four by one volume is 80.0MPa, and bend strength has increased by 90%.

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The direct metal lamination is one of the additive manufacturing processes using the arc welding technology; where the molten metal made by the arc discharge is accumulated successively in this process. In this study, two kinds of dissimilar metal fabrication were conducted. One combination is an aluminum alloy and a titanium alloy. Another is a stainless steel and a Ni based alloy. The boundaries of dissimilar metal structures were investigated. As a result, the potential of the fabrication with more than one kind of metallic material by direct metal lamination is shown.

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Because the demand of multi-axis controlled machine tool is increasing recently, the new interface functions for the machine tool are needed, which allow us the institutive, safe and accurate operation. The final purpose of our research is development of interface which operates a multi-axis controlled machine tool directly by Haptic Device. However, in the developed interface, operator's tremor disturbed tool path, and disorder of tool path deteriorated the appearance of machined surface. This report introduces the interface function that reduces disorder of tool path by approximating tool path as sets of curves and straight lines. The most difficult part in the approximation is the determination of segmentation point. In this research, segmentation points are determined by corner points of tool path and speed at the tip of device. As the result, we confirmed the decrease in disorder of tool path and the improvement of appearance of machined surface.

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A new methodology to automate machining operation planning is proposed. A new machining operation plan is reconfigured from past case data or past machining operations. Machining information, e.g. cutting tool, cutting conditions, tool path pattern, is associated with a machining feature. A machining feature to be cut is related to 3D CAD model of workpiece. Sets of machining information and a 3D CAD model is stored as the past case data. In order to generate a new process plan of a new workpiece, machining features are recognized first. Then, each of machining feature is compared with machining features contained in 3D CAD models of workpieces stored as the past case data, and the most similar machining feature is selected. The machining information associated with the selected machining feature can be applied for each of machining feature consisted in the new workpiece.

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Reduction of calculation time of tool path generation for complex 3D models is an important issue in development of CAM applications. In this study, cutting point dependent progressive mesh is applied for the models which are represented by meshes. This method maintaines history of symplification of the 3D model with hierarchical structure. 3D model can be refined and simplified by using the cutting point dependent progressive mesh. Therefore, the tool path is safely generated by reducing the number of meshes appropriately. Moreover, calculation time can be reduced. In this paper, a tool path is generated by using cutting point dependent progressive mesh, and the calculation time and the result of tool path generation are evaluated.

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It is strongly requested to develop a new CAM system to shorten the drill fabrication time, to reduce material costs, and to create a new drill configuration by predicting its characteristics. Current drill shape prediction system cannot necessarily treat drill cross-section shape including the cutting edge, groove and so on, mathematically. The system becomes practical if these drill specification is mathematically formulated. The study reports the development of a system to predict not only cross-section shape but also various parameters from grinding wheel data of drill making.

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In general, products with complex shape and unstable shape are manufactured by assembling simple parts after their machining. In place of such a production method, the study proposes the machining of products having complex and unstable shape without breaking down into simple parts, which is named "Dexterous Machining". "Dexterous Machining" allows for improving the accuracy of the products and the lead time. In the study, the purpose is to machine an unstable shape having high-aspect ratio and a large mass at the tip by providing three support pillars for applying "Dexterous Machining".

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The initial position errors that could be generated while setting the cutting tools can deteriorate machining accuracy. However, it is difficult to prevent the tool setting errors during the manual setting process, which may increase in accordance with the number of the control axes. These errors make it difficult to locate the tool accurately at the right position during multi-axis control machining. Therefore, this study aims at achieving 5-axis control ultraprecision machining by using a non-rotational cutting tool compensation. From the experiments, it is found that the proposed method is effective for the compensation.

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It is difficult to precisely machine soft objects such as rubber or sponge which have completely different characteristics compared to metals generally machined by machine tools. The study deals with the first trial of creating an artistic product shape of soft objects by employing an aqueous solution of sodium acetate to fix a workpiece and to improve the stiffness. As a result of conducted experiments, it is found that the usage of the aqueous solution of sodium acetate has the potential of realizing "Dexterous Machining" of soft objects.

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Recent, for equipment loading in factories and plants, path planning is done by using shape information of the existing equipment. As the posture of the loading product is determined directly on the scene, an efficient pre planning approach is required. In this study, a 3D measurement of the route (circumstance) is carried out under no shape information, and a method for planning route and posture without interference is developed. In this paper, a method to perform point cloud data correction obtained from infrared 3D measurement sensor is proposed. The sensor used in this study is able to collect depth value and color value (RGB) simultaneously. Therefore, by utilizing the color value, an interpolation for deficient depth value is performed.

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In order to shorten the design and development time, it is required to evaluate design product in various aspects in the conceptual design stage. This paper aims to propose a method for supporting conceptual design in the aspect of processability. First, the outline and characteristics of a design support system considering manufacturing that the author previously proposed is explained. Then, based on the existing processability evaluation methods in the downstream stages of the product design, the elements that should be handled in the conceptual design stage are discussed.

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[in Japanese]

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The drilling of microholes in brittle materials was carried out using diamond micropins fabricated by electrical discharge machining as micro-grinding tools. They can be employed because the convex parts of discharge craters formed on the tool surfaces serve as cutting edges of abrasive grains of grinding wheels. In drilling of crown glass by ultrasonic grinding using diamond tools, an increase in grinding force and the generation of cracks and chippings at the hole 〓s edges were suppressed owing to the high wear resistance of diamond. Drilling was successfully performed also in silicon, holes drilled in which are apt to have cracks and chippings at the edges, with proper drilling conditions.

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In this study, the movement of tungsten wire electrode during fine wire EDM was investigated by the direct observation using a high-speed video camera. Then, a high-speed observation model consisting of a running tungsten wire of 50μm in diameter, metal mold steel workpiece of 1mm in thickness and an acrylic small tank was built. The wire movements were observed from the rear and the side of the wire by the camera. The analyzed results showed that the amplitude and the frequency spectrum of wire vibration during wire EDM varied significantly with the machining positon of workpiece between the upper and lower wire guides. Also, the amplitude envelope of wire electrode during the process was clarified.

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In a large-area EB irradiation method developed recently, high energy density EB can be obtained without focusing the beam. Then, large-area EB of 60mm in diameter can be used for melting or evaporating metal surface instantly, and the surface smoothing of metal mold can be performed efficiently. When the large-area EB is irradiated to a sharp edge, the material removal remarkably progresses at the edge. By using this phenomenon of preferential removal at the convex part, it is expected that micro-deburring by the large-area EB irradiation would be possible. When the large-area EB was irradiated to a rollover burr generated in face milling, the burr height could be reduced. In this study, the shape changes of rollover burr were experimentally investigated by SEM observation of the cross sections. Also, unsteady heat conduction analysis in this deburring method was done with considering the movement of melting part.

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During EDM of the permanent magnet, a second magnet for the external magnetic field was set up, and the internal temperature and surface magnetic flux density on the opposite surface of the permanent magnet during machining were evaluated. It was found that even though the internal temperature of the magnet remained unchanged, the surface magnetic flux density changed when the external magnetic field was varied. In addition, the magnetic field generated by the magnet changed when a plate with high permeability was pressed onto the surface of the permanent magnet.

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This paper observes the material removal phenomena in electrical discharge machining in order to discuss the mechanism of material removal in the EDM process. Time when material removal occurs, as well as temperature of the discharge point, size and scattering speed of removed debris particles, was obtained from the observed results using a high-speed video camera. It is found that small debris perticles are removed from high-temperature discharge point and scattered at high speed during the discharge duration, whearas large debris particles are removed from low-temperature discharge point and scattered at low speed after the discharge duration.

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This paper discusses the electrode wear in electrical discharge machining (EDM) of carbon fiber reinforced plastics (CFRP) in order to clarify the mechanism of low electrode wear. Sinking EDM of CFRP using EDM oil or deionized water was carried out, and the electrode wear rate and the waveform of discharge current were measured. It is found that low electrode wear is realized in the case of EDM oil. The reason of this is carbon adhesion due to long pulse discharges. It is also found that when long pulse discharge does not occur, low electrode wear is also realized, because of increasing the gap length.

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In micro electric discharge machining, the machinability can be improved by vibrating the electrodes. However, the mechanism of vibration assisted EDM has not been clarified due to the difficulties in direct observation of the discharge area. In this study, we investigate the effect of vibration methods on machining efficiency and electrode wear by direct observation of the discharge region through a glass plate, As a result, we found that in z-direction vibration, which has been widely used in small-hole EDM, discharge is concentrated at the center of the workpiece, while by using zx vibration, the discharge distribution becomes uniform with a high material removal rate.

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It is necessary to machine holes of complicated shapes for building pipelines of hydraulic or pneumatic equipment. However, the degrees of freedom of machinable hole shapes are limited, since holes are generally fabricated by drilling. To enhance the degrees of freedom of these shapes, the authors have aimed to develop a device which can fabricate a hole on the inside wall of another hole by means of electrical discharge machining. Although it was proven that the last device developed has the ability to machine such a hole, it was found that this device has the weak point that the length of its machinable hole is short. To overcome the weak point, the improved device has been developed which is equipped with a supporting apparatus. The experimental results indicate that the improved device can make such a hole lengthened.

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Electrical Discharge Machining (EDM) has been used in micro-fabrication because of its low reaction force. We proposed a new micro-pin forming method in which a rotating electrode scans towards a forming plate. As the processing area in this method is large, a higher removal rate is achieved compared to the WEDG method. And forming of the micro-pin of 8μm diameter and 250μm length is done easily by this method. The rotational speed of the micro-pin reached critical in the process of high aspect ratio of the micro-pin forming. We consider the micro-pin rotation effects on miniaturization limits. In this study, we investigate micro-pin forming method considering the natural vibration frequency of the electrode.

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In this research, micro-pin fabrication by scanning electrical discharge machining was carried out according to two machining processes. As the first process, the shape of a groove is fabricated by scanning electrical discharge machining under the conditions of minus of electrode polarity. As the second process, electrode polarity is made to change and a micro-pin is fabricated for this machining groove as a base level. This report describes the forming characteristic of the micro-pin by this method.

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As semiconductor devices have been become smaller, measurement techniques with high resolution are required for defect detection and inspection of microstructures. Optical measurement methods are effective because of being nondestructive and their wide measurement ranges. In optical measurements, resolution is limited by numerical apertures because of influence of diffraction. We have developed an optical measurement method with resolution beyond diffraction limit. This paper describes development of the method and an experiment to obtain illumination parameters prior to super-resolution processing.

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We proposed a novel optical surface inspection method to investigate the surface defects of semiconductor wafer. A novel phase characterizing method, which is based on a cross correlation frequency resolved optical gating method, is applied to evaluate the surface nano structure of semiconductor wafer. In this paper, we describe the principle of the method and the component of originally developed equipment to evaluate the nano surface texture by using hybrid X-FROG method.

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Femtosecond pulse processing enables fine processing without the thermal diffusion. In this paper we generate femtosecond pulse train beam, which has several femtosecond pulse in a few picosecond, and investigate the processing result using femtosecond pulse train beam. It is considered the coherent phonon, which is the forced lattice oscillation due to the surface electron vibration in the high electric field, is excited on the surface in the case of irradiation both the femtosecond pulse train and femtosecond single pulse. In this paper, we measure for the coherent lattice oscillation using femtosecond pulse train

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Demands for a precise plane with a large area have recently increased in a variety of industries such as optical devices, silicon wafers, precision machining devices, etc. In order to meet such demands, high speed surface measurement over a large scanning range is required. This paper presents a proposed robust surface measurement using the proposed Hyper-Multi-Point method. The Hyper-Multi-Point method uses multiple displacement sensors. This method is not influenced by the motion error, sensor noises, etc. The evaluation results confirmed that the proposed Hyper-Multi-Point method achieves robust and high speed wide-ranging measurement.

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A diamond cutting tool tip temperature in a micro cutting of zirconia ceramics was measured by a two color pyrometer with an optical fiber. A quadrangular pyramidal, single crystal diamond was used as a cutting tool. The tool has a small hole and the optical fiber was inserted into the hole. During the cutting, the fiber accepts the infrared rays radiated from the tool-chip interface and transmitted through the cutting tool. The relationship between the types of cutting grooves and cutting forces and temperature was investigated.

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The non-contact measuring machine of the mold, its utility and significance was observed, many studies have been conducted. But the example that has been put to practical use in reality very little. In this study, we report the results of re-organized from the perspective of processing and measuring each of its problems and challenges point, we investigated the guidelines for practical use.

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This work deals with effects of manufacturing conditions on strength of metal/polymer hybrids, which are processed by a direct joining method. The joining method is realized by an insert molding using a special metal piece; on the surface of the metal piece, nano/micro scale structures are formed. In this paper, we focus on pressure in a mold and length of annealing time as the conditions. To control the condition, especially the pressure, we utilized the mold that can measure the pressure. We measured the strength of the joining products, which were processed under several conditions, and discussed the effects of the condition variations.

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Research on micro component self-assembly is required to achieve fabrication of functional MEMS devices aggregated from different components of different materials. Self-assembly is a process in which components spontaneously form ordered aggregates without human intervention. In this paper, we propose DNA self-assembly in which micro components are assembled on designated locations on Si substrate, utilizing DNA base sequence complementation and hybridization for adhesion. Surface coverage of thiol modified single strand DNA on 20μm square Au binding sites on Si substrate are measured, so as to verify the number of single strand DNA involved in the hybridization bonding between component and substrate.

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In order to measure a thickness distribution of an optical thin film, we have proposed a micro-lens array (MLA) mounted on a prism in the modified Otto's configuration for observing surface plasmon resonance (SPR). The SPR is suitable for measuring a thickness of a thin layer because the SPR is high sensitivity for the thickness of the thin layer. However, the thickness distribution cannot be measured by the modified Otto's configuration because a measurement field is limited in a generated SPR field by using a lens. To overcome the problem, we focused on the MLA for increasing a number of the SPR field. A size of the SPR field depends on a lens size, namely, the spatial resolution is improved by using the lens of micron size. In this paper, we measured the thickness distribution of the Au thin film of 50nm using the MLA of the lens 300μm in diameter. Experimental results showed that it was effective for measuring the thickness distribution by using modified Otto's configuration with the MLA.

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Inside plastic molding products, the residual can cause the degradation and we have no available system for measuring such residual stress in non-destructive process. In this report, we propose a non-destructive method for measuring residual stress in plastic molding products by utilizing THz measurement (wavelength: 50μm〜1 mm). Plastic polymers are transmissive to THz waves and their crystalline orientations, which are generated mainly by the residual stress, are also sensitive to THz waves. Here we perform experimental analyses to confirm that our proposed method is well suited for non-destructive measurement of the residual stress.

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Quenching is a useful heat treatment which changes the mechanical properties of the steels. Because narrow laser beam is irradiated on the surface of the local region, local surface layer is quenched by laser quenching. Carbon is indispensability element for martensite transformation of iron. Laser quenching of low carbon steel with thin carbon layer was investigated in this study. The effect of carbon surface layer on laser quenching was evaluated by the hardness distribution.

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The local hardening method using resistance heating is characterized by rapid heating not only low cost but also easy control of heating temperature as compared to flame hardening. It has been reported that flat surface of die steel (SKD11) can be uniformly hardened by this method. In this report, the possibility of uniform hardening of edge part of die steel was experimentally examined. The following features were revealed. Uniform hardening of edge part is possible by application of appropriate electrifying conditions. And, required current density is relatively decreased by an increase of the size of electrode in order to expand the hardening range under fixed electrode contact pressure.

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Indirect laser peening is a new laser peening technique and modifies the mechanical properties of the surface of the substrate. Metal sheet protects the substrate surface from heat affect by a plasma with laser irradiation. Because the metal sheet absorbs laser energy and reduces the peening efficiency, the features of indirect laser peening for several aluminum alloys were investigated in this study. The changes of mechanical properties by indirect laser peening were discussed by the comparison to the mechanical properties of as-received state.

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Currently, quality judgment method for super finished surface is still carried out by visual observation. However, this method may cause some problems such as misjudgment and quality difference for each examiner. The objective of this report is the automation of quality judgment method for super finished surface. Since periodic pattern appears in defect part of the super finished surface, we proposed a quality judgment method, which judges existence or not of this defective periodic pattern using Fast Fourier Transform. Power Spectrum Picture is obtained by using Fast Fourier Transform. We analyze the Power Spectrum Picture using liner forecast, and judge the surface quality. As a result, the usefulness of devised method was experimentally confirmed.

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Carbon fiber reinforced plastic has the superior mechanical properties, and various methods have been used for the molding such as VaRTM and autoclave. It has been reported that carbon fiber sheet can be heated by induction heating. And, it is chosen as heating process of molding for CFRP. General pancake coil generates the electromagnetic within plane in the specimen. So, the specimen should have enough thickness. However, heavy thickness of specimen causes the poor reappearance of mold shape. In this report, two induction coils with 40mm gap has connected in series were used for heating. And, the electromagnetic flux pass through in perpendicular to the test piece that is set between the coils. And, experiment and molding have been carried out using these coils.

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In this paper, a new joining method using rotating tool has been developed. In this method, a tool with a shoulder and bolt-shaped tip is used. This tip rotates and plunges into the workpieces until the shoulder of the tool touches the plate surface. The rotating tool forward through the workpieces, the two plates are joined without any preprocessing. Therefore, this method is considered to have a decreased number of processes. This method was used to make lap joints, and the joint strength of the joined aluminum alloy plates was investigated using a tensile shear test. In all cases, the tool plunge rate was kept constant at 20mm/min, and the tool rotational speed was set to 765-1890r/min. The tool, which is made of SKD11, has a shoulder diameter of 10.0mm, a cylindrical tip diameter of M3-LH and a length of 4.0 mm. As a result, the workpieces are joined by frictional stir, and the maximum tensile shearing loads of all the samples in this study were more than 3.4kN, those the samples can be joined with high strength.

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