Recently, Life cycle assessment(LCA) has been attracted attention in the manufacturing fields. Some consumption devices has been designed considering LCA. Therefore, we start a study about the miniaturization of the machine tool with LCA. In this study, we focuses on the miniaturization and multifunction in a cell production system. In the present report, we consider about a phase of "heat-treatment process of the small cell production system" from a view of power consumption to estimate its LCA

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A simulation system for chatter vibration has been developed by calculating an end milling process in time domain with considering a regenerative effect which is a kind of nonlinear behavior. An influence to the chatter vibration of a cutter runout is also analyzed in this paper. Consequently, the vibration changes according to the radial runout offset, but the cutter runout doesn't affect the occurrence of the chatter vibrations.

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A new scheduling method, in which the load balance of each process can be considered, in a flow shop type production for a wide variety of products is proposed. In this method, a production schedule is generated under consideration such as a work breakdown structure, processes and processing time required for each product. Processing time of all operations is represented by a discrete unit time, and the load distribution of each process is identified easily. GA (Genetic Algorithm) is applied to generate product plans and the most suitable plan, in which the maximum load satisfies the process capability, is selected.

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In machining process, especially multiaxis NC machining, it is necessary to simulate the motion for confirmation of NC data. Recently, machine tool systems consist of not only machine tools but also auxiliary devices such as robots, then the systems are complicated. In such case, there are two problems; 1) There is no common integrated model of kinematics and shapes for machine tools and robots. 2) There is no unified solving method of inverse kinematics with machine tools and robots. In this paper, to solve these problems, an integrated model of kinematic model and shape model for machine tools and robots based on STEP(ISO10303) is proposed. A motion simulation system including a unified solving method of inverse kinematics using Groebner Basis is also developed. Then, an example of the integrated model and solving inverse kinematics for machine tools with robots using this model are also demonstrated.

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The paper describes the conceptual design study on the process planning support system for machining parts of machine tool systems. The system aims the full and direct utilization of 3D solid model part data obtained in the design process of a machine tool and the realization of computer based processing chain to generate the process and operation plans to machine parts as well as all necessary information for CNC parts machining operation including CNC programs and machine set-up data). The paper contains the background of the study, the concept of the system and the expected outcome to be obtained from the study, and general flow of the proposed process planning support system.

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In recent years, five-axis controlled machine tool attracts attention from the increase in the demand for the improvement of productivity. A square end mill is often used for rough cutting, because it has much removal rate. However, five-axis controlled machining with the square end mill is more difficult than in case of ball end mill. In this report, we will propose the tool path generation method for five-axis controlled machining with square end mill. By using this method, the position and the posture of end mill which were near the interference surface as much as possible were searched along the character line, and the tool path which moved the square end mill near the character line was generated. As the result of simulation, we confirmed the generated tool path was able to minimize the cutting remains near the character line.

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The study deals with automation of deburring by industrial robot. The study focused on automation of deburring with positing error. While general, deburring system using industrial robot decreases error using force control and path based on the CAD data, the system uses displacement sensor to measure trajectory error. From the experimental result, the system is found to be improvement of path compensation accuracy in corners.

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The paper discusses micro cutting of ultra fine grain steel with measuring the cutting force, the shear angle and the shear stress on shear plane. The cutting tests were conducted in a planing manner on the developed machine tool. The dynamic component in the cutting force of the ultra fine grain steel is less than that of the normal grain steel. The shear angles were measured with changing the cutting depth. The shear angle increases with the cutting depth. The shear angle of the ultra fine grain steel is larger than that of the normal grain steel. Although the effect of the grain size on the shear stress on the shear plane is not large, larger scattering is observed in the shear stress of the normal grain steel for the cutting depth.

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The micro drilling is difficult to put the cutting chips. Therefore, the drill can break a large torque. To solve this problem have been developed to put out chips causing the cavitation in the hole by ultrasonic vibration. This report is a comparison of reports from the surface roughness and processing time for this method.

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In order to extend operating life of artificial hip joint, new manufacturing process of micro-crater on Co-Cr-Mo alloy surface using electron beam-irradiation and polishing have been proposed. The electron beam-irradiation could form micro-craters with 60 micrometers in average-diameter and about 10 micrometers in maximum height for 10 minutes. These micro-craters would have the similar shapes of live hip joints. The pin-on-disk friction tests were carried out for evaluating the lubricity.

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The paper discusses wettability of micro-scale structure on surface. The micro-scale structures are manufactured in the following processes: (1) machining of the structure tools in FIB sputtering, (2) incremental forming for structured molds and (3) plastic molding. The micro-scale structures promote hydrophobicity on the polyethylene surface. Then, the structured surfaces are treated to change the wettability in plasma irradiation. The plasma treatment changes hydrophobic structured surfaces to hydrophilic ones. The wettability of the treated surface reaches the steady state after 120 hours. The contact angle decreases with the solid fraction on the hydrophilic structured surface. However, the most hydrophilic surface appears on the flat surface treated by the plasma irradiation. The droplet tests were performed to verify the edge effect of the micro pillars with measuring the change in the contact angle with the amount of the liquid.

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This paper discusses the patterned self-assembly of fine particles and its application to grinding tools. By combining dipenser and stage control, aqueous colloidal suspension was deposited on the required portion of a substrate. With the evaporation of solvent, dispersed particles made-up packed structure. Simple patternings of lines shows that thin line as 20μm width can be patterned. Then, spiral pattern was attemped as a tool considering flow of the coolant and space for chips-pocket along with the rotaion of tool. Finnaly, self-assembled particles were transferred to another substrate using Photopolymer to keep the tool height at constant independent of the layers of assembly in addition to the fixation of the particles.

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In this paper, fabrication of a 2D ordered nano-dot array using the combination of Nano Plastic Forming and annealing processes is reported. Experimental works are conducted to confirm its feasibility. First, quartz glass substrate is coated with a thin layer of gold (10nm). Second, a knife edge diamond tool is utilized in the Nano Plastic Forming process to fabricate cross pattern with various pitch settings on quartz glass and gold layer surface. Third, the substrate is annealed at 700℃ for 10 minutes to induce self-organization. As a result, 2D gold nano-dot array down to 100nm size with 250nm pitch is successfully obtained on the surface of quartz glass.

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The paper presents a micro dimple machining on the cylinder surface with combining rotations of the workpiece and the milling tool. The cutting parameters are determined so that the removed areas are not overlapped. A ball end mill is positioned at an orientation angle of 45 degree from the top of the cylinder to incline the cutter axis with respect to the tangential direction on the cylinder surface. The mechanistic model is also presented to simulate the shapes of the dimples with the cutting parameters. The presented machining is verified by the dimples in cutting tests and simulation results.

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Plastics are regarded as proper materials for microfluidic chips, and, in particular, biodegradable plastics will be more appropriate from the viewpoint of environmental friendliness. In addition, when they are utilized as chip substrate, biochemical machining can be applied. Biochemical machining is a process which utilizes enzymatic biodegradation. For practical use of biochemical machining, it is necessary to develop arbitrary shaped fabrication methods. This paper proposes an application of gel electrophoresis to shape control method of biochemical machining of (poly(L-lactic acid) (PLLA) by enzyme (proteinase K). With current, proteinase K moves in the direction of cathode, and then, the gradient of enzyme concentration occurs in the gel. This gradient generates the difference of degradation amount, depending on position. This result means electrophoresis has feasibility for shape control method for biochemical machining.

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In general, it is known to be able to control the tribological performance by generating a microsurface texture on the surface of the sliding parts. However, effective method that enables the generation of the microsurface texture of the inner hardened sliding parts of small hole is not considered. Thus, as an efficient method to fabricate a microsurface texture for hardened sliding parts, "Electrical discharge texturing (EDT)" was examined. A more efficient approach, "Whirling electrical discharge texturing (WEDT)" method was developed. And the fundamental characteristics of WEDT were clarified.

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The new texturing method named an Electro-Chemical Discharge Texturing (ECDT) was developed in the present study. The crater was formed on the glass surface using the ECDT instrument developed. At First, the influence of electric conditions on the formation process of the crater was clarified in order to control the crater shape. Then, it was found that the textured surface was obtained through the patterning experiment using ECDT instrument. As a result, the possibility of the generation of microsurface texture with the ECDT method was shown.

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Composite abrasives have been developed for improving the dispersibility and cleanability of the conventional glass polishing that uses cerium oxide abrasives. The composite abrasives are fabricated by adhering cerium oxide abrasives to the surface of polymer particles using a hybrid mixer. In this report, the effect of retention of composite abrasives on the polishing performance are investigated. The composite abrasives exhibits higher removal rate by up to 50 percent than the conventional glass polishing. The waviness and edge characteristics of glass surface are also improved using composite abrasives.

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Cerium oxide (CeO_2) abrasives are conventionally used for polishing process of hard-brittle materials, such as crystal and a glass FPD panel. However, the process with cerium oxide abrasives has some problems (1) hard to invade polishing fluid to the center of workpiece in case of large sized panel during processing and (2) hard to cleaning the surface of workpiece after processing and this causes the high processing cost. In order to solve these problems, an abrasive-free pad etching process of glass mirror polishing has proposed for the purpose of replacement of the cerium oxide abrasives. As the result of a series of pad etching tests on the glass workpieces, we have obtained high removal rate and the surface roughness of under 20nm Ra.

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Copper (Cu) have been conventionally finished by the chemical-mechanical planarization/polishing (CMP) method with abrasives for obtaining the ultra-smooth surface. The method, however, has serious problems such as scratches and projections caused by the abrasives. To overcome this problem, the abrasive-free polishing (AFP) method utilizing vacuum ultra-violet (VUV) light irradiation and electrolyzed water was applied to the finishing process after the Cu-CMP. As the experimental results, the ultra-smooth surface less than 1 nm Ra (average roughness) and 10 nm Rp (peak valley) in the relatively-large area 700 x 500μm square can be achieved.

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Cerium is one of rare metals to have high risk so that it is strongly required to reduce the usage quantity. As the usage of cerium, the ratio used as an abrasive grain is high. Cerium oxide is a polishing agent of glass to use commonly. Then we started the research project to improve the removal rate. When an epoxy-resin polishing pad was employed instead of an urethane polishing pad, it was found that the removal rate exceeded the twice of conventional polishing. In this paper the reason of high removal rate was investigated. As the result dynamic friction coefficient of epoxy-resin polishing pad was extremely high in wet state so that abrasive grain was difficult to move. The inclination experiment confirmed that it was difficult to flow the slurry on the epoxy pad. Next an alternative abrasive was examined. Commercial zirconia abrasive grain had the possibility to become a substitute abrasive when epoxy resin pad was used as a polishing pad.

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Authors have been developed a novel polishing method using functional fluids which are dispersed abrasives with silicone oil. This fluid shows active reciprocate motion between electrodes under AC electric field at very low frequency. In this study, we have reached the 3 times the polishing rate using controlled slurry under AC electric field for the substrate of silicon carbide, as the next generation power electric devices.

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This study deals with polishing using abrasive water jet for corner parts of a mold. In general, abrasive water jet is applied to cutting process of various material. In our past report, the surface roughness of 0.058μm(Ra) was achieved on polishing for plane surface of mold. This report shows result of experiments to investigate relationship between injection pressure of abrasive water jet and the incident angel from workpiece and relationship between incident angle and abrasive energy which is thought to affect erosion on polishing surface using abrasive water jet.

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In machining process of glass component, some extent of residual stress is necessarily introduced in the component. The affected layer influences the profile accuracy of the component. However, it is difficult to measure thickness of affected layer on amorphous material. In this paper, we propose new method to evaluate thickness of the affected layer on glass surface. The proposed method is based on deformation of material according to removal of material surface. In order to verify applicability of the proposed method, we measure residual stress of soda-lime grass and BK7. As a result, we found condition for the stable etching of soda-lime glass and BK7. And the proposed method was applied to glass material, and thickness of residual stress layer was evaluated.

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In recent years, since electronic devices become smaller, it is required that microparts should be machined accurately. CAM systems generally focus on generating NC data. Consequently operators have to make the process planning by considering the features of the machining process. The process planning is more important when microparts are fabricated. This study deals with the development of fundamental CAPP/CAM system, which can automatically detect high-aspect-ratio structures, offer suitable cutting conditions and generate tool paths by calculating the bending moment induced by cutting forces.

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This paper dealt with the relationship between tool wear properties and internal defects of diamond tools.FT-IR analysis were done to determine qualitative amount and kind of internal defects. The analysis suggested that N_2 impurities as an internal defect affected the crater wear significantly.

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In this paper, cutting experiments on a single crystal silicon substrate under high hydrostatic pressure are carried out and discussion from crystallographic aspects is reported. For this purpose, a lathe type machining device which can withstand high hydrostatic pressure up to 400 MPa is specifically designed and developed. Using this device, damage free machining of hard-brittle material is possible. Experimental works are carried out on silicon substrate under 0-100 MPa and its surface roughness is measured. It is found that the surface roughness on machined surface to <110> direction is higher than to <100> direction. Effects of hydrostatic pressure medium and crystallographic orientation on this phenomenon are discussed.

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Lubrication is a key issue in diamond turning of hard materials. In this paper, the feasibility of nanoparticle lubricated tool-swinging cutting of SiC and WC was investigated. Four kinds of nano particles were dispersed in lubricating grease and then applied on workpiece surface. Results showed that the type and the concentration of the dispersed nano particles significantly affected the lubricating performance. Base grease containing 10% Cu nano particles produced the lowest surface roughness and the smallest tool wear. The lubrication mechanism was discussed from the viewpoint of solid lubricating film formation at the tool-workpiece interface.

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Plated alloy have been attempted to improve heat and wear resistance and insulation properties of machine parts. Particularly alloy of nickel and phosphorus(Ni-P) have benefit for the mold of glass or plastic lens which have property of highly heat and wear resistance. Ordinarily the plated Ni-P is made by a process of electroless plating. In this study, I used the plated Ni-P which made by a process of electroplating. In this process, a plated alloy can contain more amount of phosphorus. Single crystal diamond turning experiment for the cylindrical end face plated electrolytic Ni-P was carried out, and analyzed the potential of ultra precision cutting of electrolytic Ni-P and the effect of amount of content phosphorous. It was turned out that Electrolytic Ni-P have potentiality to be worked as electroless Ni-P, and to improve the surface roughness by the increase of the amount of content phosphorous.

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The lead magnesium niobate-led titanate (PMN-PT) piezoelectric single crystals were ground by a ultra-precision surface grinder with various cup-type resinoid-bonded diamond wheels under a wide range of grinding conditions in order to obtain thin plates for ultrasonic transducers. As a result, thin PMN-PT crystal samples of 4μm thickness were obtained by this grinding process.

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Demands of the production of the wide area lens array mold, such as Wafer Level Lens Array, are increasing strongly. In addition, it becomes to be one of the essential factors that not only the quality of each lenslet but also the location accuracy and the stability of the manufacturing process would be achieved. In this study, the optimized process is proposed that the strategy using B table enable more precise and stable cut location accuracy. In the result approximately 0.2μm as cut location error could be obtained over 120 hours lens-array cutting examination.

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In die production of seat and film for optics aimed for diffusion, demands of high precision machining increase to make three-dimensional micro-pattern, recently. When irregular micro-pattern is processed by piezo-dirve stage with the cutting tool, there is the problem that a cutting tool contact, because it is impossible with a random command signal by noise to predict a tool trace. In this study, it tried to examine an effect by machining designed complicated micro-pattern.

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Needs of aspheric lenses are increasing for digital cameras or mobile phone. In the conventional fabrication process, molded axis-symmetric aspheric lenses were assembled on the CCD chip. In this conventional process, productivity was not high and new assembly process is required. Recently, WLC (Wafer Level Camera) fabrication process is proposed. In this report, precision machining of micro lens array mold is examined. Electronless Ni array mold is machined with micro milling tool made of single crystal diamond and the accuracies of the array mold are evaluated.

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It is known that tool-work thermocouple method is convenient and effective to measure cutting temperature. However, the EMF characteristics between tool material, and work material has to be measured with special equipment before cutting tests. The EMF characteristics between tool and work estimated from EMF characteristics of tool material and work material obtained by using dynamic measurement method was compared with actual EMF obtained with special equipment. As a result, it was demonstrated that the estimated EMF characteristics between tool material and work material was similar to actual EMF characteristics although the estimated EMF was a little larger than the actual EMF.

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Demands for measuring three-dimensional (3D) micro-geometries over a large scanning range have recently increased in a various industries such as aerospace, dies and mold, energy, etc. This paper presents a newly developed 3D profile measuring system with both a large scanning range (18mm×18mm×10mm) and a nanometer resolution. The profile measuring system developed is consisted of an AFM probing system and a newly developed 3D nano-motion system with a large travel range. Eliminating motion error of the nano-motion system enables the AFM probe to scan a specimen with a nanometer resolution. The results of actual measurement for an optical lens confirmed that the developed system achieves high measurement accuracy over a large scanning range.

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In this paper, a new temperature sensor was proposed in order to measure cutting temperature fields continuously with a quick response regardless of the conductivity of a work. It has thermocouple array constructed by a tool and sputtered metallic lines, which are embedded into a cutting tool rake face. Here is a process flow. The trenches and electrodes were milled by femto second laser. And, insulating films and metallic lines were sputtered on the rake face. Finally, unwanted films were removed selectively by polishing. The thermo electromotive force of our sensor was converted to temperature based on a calibration curve obtained by experimentally. Cutting experiment showed that cutting temperature at the rake face could be measured by our sensor.

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This paper deals with the tool feed rate optimization for smoothening of cutting force in end milling of workpiece with corner and straight parts. There is a difference between the cutting force in a corner part cutting and that in a straight part cutting. This is due to the difference in the instantaneous depth of cut in both cuttings. The scheme of this study is to prevent the generation of excessive cutting force in the corner part machining by comparison with the straight part machining. By dividing the NC cutting path of the corner part and changing the tool feed rate in each division, the cutting force in the corner part has been controlled.

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Tool wear occurs in the ball end milling, and it increases with the cutting distance. It gives undesirable influences on the machining accuracy and that prevents high accuracy ball end milling. If necessary, the dimensional accuracy of parts has to be improved by a post process such as grinding. However, the post process lowers machining productivity, machining time becomes longer and machining cost becomes higher. The purpose of this research is to investigate the behavior of machining error due to tool wear during the ball end milling of inclined plane by a long time continuous cutting and to compensate the machining error. The compensation is carried out by increasing the depth of cut in NC program when the machining error reaches a threshold value. The validity of this compensation method is confirmed by experiments.

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In this paper, a simultaneous measurement of profile and surface topography of a grinding wheel by image procession is proposed. The rough of abrasive and the successive cutting edge spacing of super abrasive electro-deposition cylindrical wheel are measured as the surface topography. The shade images of the rotating wheel are projected to monochrome CCD camera by parallel optical lighting. The image that composes of the maximum value of the light and shade value of the pixel is defined as the Maximum image. The image that composes of the minimum value of the density value is defined as a minimum image. The outline of the minimum image corresponds to the wheel profile. The outline of the maximum image corresponds to the wheel base. The maximum image is subtracted from a minimum image, and the width of a remaining image is an amount of the abrasive asperity. The edge position of the image changes along with the wheel rotation angle. The successive cutting edge spacing is derived from this change. The effectiveness of the measurement methods were verified by the experiment and the numerical simulation.

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Recently, the demand for precision machining of dies and molds with complex shapes has been increasing. Though high performance CNC machine tools are applied widely for precision machining, machining error compensation is still necessary to meet the machining accuracy requirements. Usually, for precision measurement, a workpiece must be unclamped from a CNC machine tool. Then, the workpiece is measured by precision measurement device such as 3D CMM. After the machining error is clarified according to the result of measurement, the workpiece must be re-clamped for the machining of error compensation. However, the error compensation requires a highly skill of machinists, and spends a large amount of time and cost. Additionally, re-clamping of the workpiece causes positioning errors. Therefore, demands of an On-the-machine Measurement have been increasing. This paper describes an On-the-machine Measurement device that consists of a Line laser displacement sensor. This measurement device is attached on a spindle head of machine tool using magnetic clamps, and has special features that achieve non-contact scanning measurement, multi-point measurements, high-speed measurements, and the measurement of both the vertical surface and the steep slope.

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Mitsubishi Heavy Industries developed a precision high-speed cutting processing machine for a precision die and mold, electrode, and highly accurate parts, and is selling it. We also develops"Optical image type tool measurement system" that was able to understand behavior in the bottom of tool including the thermal displacement of the machine by an operation condition, that was not able to recognize it with an usual tool measurement device. The method of measurement is measured by noncontact by putting the tool between the LED lighting and high resolution CCD camera, and taking picture of the shadow of the tool. Operator can get the best condition of the machine only input the necessary accuracy, without considering of the warm-up time.

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In drilling, excessive temperature rise is known to cause various types of thermal damage to the drilling tool and workpiece. Here, we study a temperature variation of the bottom of the hole during drilling using a newly developed infrared radiation pyrometer equipped with two optical fibers. One of the optical fibers is inserted in the oil hole of carbide drill and runs through the inside of the machine tool spindle. The fiber connects to the other optical fiber, which is connected to the two-color pyrometer, at the end of the spindle. Drilling is conducted by using stainless steel plates of different thicknesses. The temperature increases with increasing drilling depth. The increasing rate of the temperature rises near the exit of the hole by the heat storage effect.

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In the machining of titanium alloy in dry condition, it is well known that the chip may spontaneously ignite and combust under the condition of high cutting speed and small undeformed chip thickness. Here, we measured the chip temperature in high speed turning of titanium alloy by infrared radiation pyrometer with an optical fiber. The cutting process is recorded by a digital camera to observe the chip combustion. When the depth of cut is 0.2mm and the feed rate is 0.01mm, the chip combustion occurs over the cutting speed of 800/min. The chip temperature is 880℃ and 950℃ at the cutting speed of 600m/min and 800m/min, respectively. The chip combustion is more influenced by the cutting speed than the feed rate.

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The dimensional accuracy of workpiece worsens because of thermal deformation by grinding heat in the cylindrical grinding. Therefore, it is necessary to understand thermal deformation behavior of the workpiece, but temperature changes in the workpiece are not clarified sufficiently. In this study, temperature distribution and thermal deformation of workpiece are simulated, and validity of these simulated results was verified with comparing to measured results by developed measurement system of temperature in the workpiece.

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The dimensional accuracy of workpiece worsens because of thermal deformation by grinding heat. In this study, to reduce the dimensional error thermal deformation of workpiece during grinding process is calculated with developed simulation analysis method. In simulation, the heat inflow and outflow are calculated with comparing the measured temperature on the ground workpiece surface. The surface temperature can be obtained easier compared with the grinding force that used as the input of conventional simulation method. By using this new simulation method, it is confirmed that the thermal deformation of the workpiece correlates with workpiece surface temperature at steady starts. The outflow heat from workpiece has constant value even if the coolant flow increased.

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Superfinishing makes fine surface because the machining state transits from cutting to finishing during short time. However it is difficult to monitor the transitions of machining condition for setting the best finishing condition. So in this study, an advanced in-process monitoring method is proposed and the measurement system is newly developed. The machining state is judged by the in-process measurement of stone head displacement with the developed measurement system attached to the machine tool. It is observed that stone head displacement decreases after the transition of machining state and critical pressure is obtained experimentally.

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These days, micro-processing has been increasingly demanded with downsizing of manufacturing products. Micro-grinding is one of methods to create a sub-millimeter size structure, such as micro-holes, micro-lenses and dental form-grinding. Due to using wheels with small diameters, ground surface textures could be worsened in micro-grinding. In this study, ultrasonic-assistance was employed on micro-grinding to improve the ground surface texture. Moreover, the surface improving mechanism of ultrasonic-assistance was considered based on the tip angle flattening effect of ultrasonic-assistance. As a result, the ground surface textures could be improved with ultrasonic-assisted micro-grinding and the surface improving mechanism of ultrasonic-assisted micro-grinding was confirmed experimentally.

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Functional surface has been required to improve optical property, contamination resistance and antiwear property. Powder jet processing is a novel machining process to fabricate functional surface because it is a low cost and highly efficient method. In powder jet processing, accelerated ceramic particles are impacted on a substrate, and particles partly remove the surface of substrate or deposit on the substrate. In this study, the effect of high speed alumina particle impact on glass substrate is studied. It is found that critical accelerating gas flow rate to crack by single particle is 2 L/min and that material removal starting point is 7.4〜15 mg/mm^2.

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Micro fabrication on cylindrical surface, e.g.fluid dynamic bearings , is mainly carried out by chemical etching. However, there exist some problems in environment load by the waste fluid processing and safety of work using chemical liquids. On the other hands, blasting is expected as one of micro fabrication methods and progresses to use for not only surface modification but also hard and brittle materials. The purpose of this study is to make clear the fundamental informations in blasting cylindrical workpiece. Therefore, machining characteristics in blasting of rotating workpieces are experimentally investigated, analyzing stock removal and surface roughness.

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