Reduction of surface roughness was experimentally investigated for mold material by controlling the pulse duration and the waveform of microsecond pulsed Nd:YAG laser with 532nm wavelength, which stabilizes the absorption of laser energy to material. In the case of rectangular pulse waveform, the range of power density without the edge formation becomes wider around 4.5 μs pulse duration. The wider range of power density without the edge formation can be achieved by controlling the pulse waveform, and the surface roughness can be reduced by apporoximately 1/4.

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The surface modification of CVD diamond with femto-second laser irradiation has been studied. CVD diamond films grown on cemented carbide tools were irradiated with 550 fs laser pulses. At higher fluence, CVD diamond has ablated. At lower fluence than ablation threshold, appearance of CVD diamond surface hasn’t changed but the surface quality has changed. The effect of surface modification is observed by Raman spectroscopy. The results of Raman spectroscopy show increases into both crystalized diamond and I_D / I_G ratio.

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Manufacturing technology for three-dimensional nanostructures has been required. In this study, we proposed a laser additive processing method in vapor phase aiming for fabricating three-dimension structures with nanoscale resolution, by utilizing optical trapping potential to confine particles in a range smaller than diffraction limit of laser beam. In this paper, we developed the equipment for basic experiments of which the intention is to investigate the relation between the shape of optical trapping potential and the performance of particles confinement. We would use Bessel beam, which propagates without changing its intensity distribution in a certain length, for particles confinement in this basic study. We conducted microparticles confinement experiment in liquid phase as a basic examination.

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We propose a laser slicing technology which is a new precision cutting technology for a semiconductor substrates. In this method, micro laser marks are created inside material by focusing laser beam. A scanning laser beam, then, connects the laser marks so as to realize cutting semiconductor materials with small material loss. In this report, in order to clear the characteristics of the technology, three materials which have different crystal structure and material property such as Si, SiC, MgO were compared. We found that the slicing mechanisms of each materials were different because of the crystal structure．

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In recent years, portable information devices have rapidly advanced in performance and miniaturization. The build-up process is often used in the manufacture of printed wiring boards (PWBs) for high-density circuits. Presently, CO2 laser beams are generally used in the build-up process to drill blind via holes (BVHs) that connect copper foils. Cu direct-laser involves complex phenomenon as a result of drilling copper and resin, with different decomposition points, at the same time. However, only few studies have been made in this field. This report focuses on monitoring Cu direct-laser drilling with a high speed camera. We have drilled with 2 different laser power outputs of 75 W, 95 W, and analyzed the temperatures of the scatter of the resin during drilling process. In this report, image two-color method was used. As a result, we have established a method to determine inflection point of hole diameter and inner layer penetration time.

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This study focuses on Powder Bed Fusion (PBF) technique, which is one of the process of the metal-based Additive Manufacturing (AM). In PBF technique, the metal powders are melted by a laser irradiation and solidified as a built structure. However, the spatter particles are generated from the melt pool during the PBF processes. Spatter particles causes deterioration of building accuracy due to the adhesion to the surface of the built structure. In this study, the laser irradiated area is observed by using a high-speed camera, and the melting and solidification of metal powder during PBF process are investigated. The influence of surface roughness in the substrate on the scattering ratio of spatter particles is evaluated. As results, the size of droplets generated around the melt pool was influenced by the surface roughness of the substrate, and the scattering ratio of spatter particles increased with decreasing the surface roughness of substrate.

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[in Japanese]

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This study presents investigation of simulation method using SPH method and FEM for waterjet penetration .Waterjet is used for processing various materials, but simulation method of water jet has not been established. In this study, motion of water was analyzed by the smoothed particle hydrodynamics (SPH) method and deformation of solid body was analyzed by the finite element method (FEM). Validity of analysis results was examined.

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Carbon fiber reinforced plastic (CFRP) is an attractive material because of high-strength and light-weight. Drilling or laser processing are generally employed to form holes, of which performance is not necessarily satisfactory. In this research, the feasibility of ultrasonic punching technique was assessed for thermoplastic and thermosetting CFRPs. It was found that the softening of a resin by frictional heat becomes the key to pierce the CFRP plates with a punching tool.

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Machinability of Inconel 718 is remarkably poor, so cutting is carried out in the low speed region at the production site. On the other hand, in recent years, high-efficiency cutting by using a ceramic end mill has been put to practical use in rough machining, but there are some problems such as welding on tools, short tool life, poor finished surface. In this study, the influence of gas blow supply to cutting point on welding and tool life in high-speed cutting of Inconel 718 was investigated.

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On the machining of CFRP with conventional tools, there are problems such as delamination and fiber out. Then woven metal wire tool with electrodeposited diamond grains was proposed by the author’s research group. However, the mesh of the wire netting is copied on the machined surface in the trimming process on the periphery of CFRP plate. If the axial vibration to the grinding wheel at some amplitude and frequency can be given, it is thought that the surface roughness can be improved. Influence of vibration condition on machined surface was investigated by experiment and simulation.

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On deep cylindrical inner surface with a small diameter, diameter of the grinding wheel and tool shaft are restricted by the inner diameter. As the grinding wheel diameter become large, contact arc length and grinding force become larger, and tool shaft deflection and grinding heat also increase. These cause the inner surface diameter error. Then the simulation was developed estimate the inner diameter error based on the size of the grinding wheel diameter and the tool shaft diameter and the grinding heat. From the grinding experiment, it was shown that the error of inner diameter was improved by 2.5 μm when the wheel diameter was changed from 9.3 mm to 8.3 mm. The error was also improved by 5.5 μm when the shaft diameter was changed from 7.0 mm to 8.0 mm.

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This paper presents a novel surface finishing technology for free-formed surfaces of three-dimensional (3D) printed resin organ models. Demand for the medical applications of three-dimensional layered fabrication technology such as organ models is increasing. Surface integrity deteriorations due to laminated micro steps formed on the surface is a significant problem. In general, material removal of layered micro step is performed manually, hence automation technology is desired. In the present study, we proposed a quasi-constant machining force grinding / polishing by use of 3-axis CNC machine tools. The workpiece is fixed to the flexible mechanical structure, whose translational flexibilities are designed to be identical regardless of contact directions and low spring rigidity. With the developed machining system, the liver model processing was demonstrated. Experimental results verified the feasibility of highly-efficient abrasive machining.

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In the present study, to improve the surface characteristics of magnesium alloy, the joining of hard ceramic powders on magnesium alloy by shot lining method was investigated. Shot peening was performed with a centrifugal-type machine using cast steel ball. The lined material was aluminium foil with hard ceramic powders, and the workpiece was the commercial magnesium alloy AZ31. The lining experiment was performed at 573 K in air. It was confirmed that the present method could be used for the formation of hard films on magnesium alloy.

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The effects of projection conditions on the surface characteristics of stainless steel were investigated. The equipment were used an air-type machine and ultrasonic peening machine. The microshot media used were high-carbon cast with an average diameter of 0.1mm. The surface hardness data showed that, in the case of microshot peening, work hardening extended deeper than the mean diameter of the media. In addition, in the case of ultrasonic peening, the surface hardness increased slowly with the projection time. Improvement of the fatigue strength was observed by both treatments. The higher effect was found in the ultrasonic peening treatment, because a work-hardened layer was formed deeper in the material.

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Powder jet deposition (PJD) is a technique to deposit material on the target under atmospheric pressure and room temperature. It has been tried to apply on dental treatment by using particles of hydroxyapatite (HA), the main component of human teeth. Prototype PJD equipment was developed in the previous research, but problems such as unstable and inefficiency jetting of HA were confirmed. In this research, we developed HA compacted powder-adopted PJD system to realize quantitative jetting of HA particles. Moreover, shape optimizations of the internal flow path were tried in order to solve the problems of PJD systems. As a result, it was confirmed that particles scattering causes particles to adhere to the wall, and that the collision of HA particles to the wall surface can be reduced by applying the expansion-and-reduction section at curving part of the flow path.

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This study aims at contributing to higher performance for manufacturing process of semiconductor by improving CMP technologies. Chemical Mechanical Planarization (CMP) is one of the most important process to get high performance and miniaturization for semiconductor. We use pad to polish silicon wafer as semiconductor substrate, but we need to polish surface of pad because the surface is going to get worse during the process. To polish pad, we use a gadget called diamond conditioner. We tried to clarify their best moving condition, less grinding resistance and better surface roughness, of pad and diamond conditioner by using CMP machine. We changed rotational speeds of pad and diamond conditioner and oscillation speed of conditioner. The result of the experiments, oscillation speed of conditioner is the primary factor in determining grinding resistance, and both rotational speeds don’t affect it so much. The most important moving condition of conditioner is conditioner’s oscillation speed. When it moves fast in the outer area of pad, its grinding resistance is small. However, too fast oscillation speed causes bad surface roughness.

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In cylindrical grinding, dimensional error occurs due to thermal deformation of a workpiece. Therefore, to improve the accuracy of the ground workpiece, it is necessary to develop the grinding system that can consider the thermal deformation of the workpiece. In this study, a new grinding system is developed, in which thermal deformation of the workpiece can be calculated using simulation analysis from the power consumption of grinding wheel motor. The developed system can estimate the net stock removal that is defined as the stock removal after the workpiece shrunk. The grinding experiments were carried out to verify the grinding system under various dressing conditions.

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In recent years, the development of sustainable renewable materials by natural resources has been progressing in response to global environmental destruction.The authors have been focusing on the fact that there are many natural and fast-growing species in Japan, and research on sustainable production systems The bamboo fiber was extracted by a machining center and the forming of the spur wheel was carried out by the hot press method.This paper describes the bamboo fiber We used the gears to carry out the test, and measured the rotational direction vibration.

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In this research, we aimed to prepare a hemispherical shell molded body by a new one step simple hot press molding method. As a result, we succeeded in making a hemispherical shell molded body by a simple hot press forming method with one step using bamboo powder, the fiber length of bamboo powder to be used is small, the larger the bulk density is, the more It can be formed.It was also confirmed that bamboo powder flows in the direction of the die end for the hot press molding method by measuring the pressure at the time of molding with the pressure sensitive sheet and measuring the density of the molded body. It was found that a pressure of 10 MPa or more was exerted on the part where the hemispherical shell molded body turned black.

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To decrease the environmental load and waste cost of water-soluble cutting fluids, we have focused on the water recycling system for waste water-soluble cutting fluids. In earlier studies, we found that some waste-water soluble cutting fluids can be processed in the recycling system. Especially, an amine-free cutting fluid showed good recyclability in lower costs and has better or equal cooling and lubricating performance compared with other types of coolants. However, the amine-free water-soluble cutting fluid showed poor corrosion inhibition performance in general machining operation. Moreover, the surfactant used in recycling process worsening the corrosion inhibition performance of the recycled water-soluble cutting fluid. In this study, we employed three types of surfactant for a corrosion inhibition performance improved amine-free cutting fluid, and examined the changes of corrosion inhibition performance of the recycled coolant.

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Organo-chlorine compounds have widely been used as an effective extreme pressure (EP) additive in metal working fluids because of their excellent performance in various metal working operations. However, environmental and safety issues demand to replace these chlorinated oils by chlorine-free oils. One of the major replacements would be organo-sulfur compounds combined with overbased sulfonates. It has been well known that, this combination shows the higher performance than that of organo-sulfur compounds alone. Regarding such high performance, in this study, we showed that calcium carbonate greatly contributed to the synergistic lubrication effect. We further found that the combination lubricant provided much low friction compared with organo-sulfur compounds alone.

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Because of effective machining operations with a very small amount of cutting fluids, near-dry machining attracts increasing attentions for environmental and economical benefits. MQL machining has so far been recognized as the most representative near-dry method and it is highly successful in machining of most ordinary steels. Recent concern for environmentally friendly manufacturing further encourages the attempts at applying near-dry operations to machining of difficult-to-cut materials. Since titanium alloys are typical difficult-to-cut materials, this paper investigates the cutting performance of various near-dry methods in turning of a titanium alloy from the view point of elongating the tool life. As a result, coolant mist supply provided longer tool life than that of the regular MQL operation or dry machining.

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Fabrication process of the pad has been developed by imprint method with special zig to control of the thickness and patter and electrode structure. Movement of the fine particle is controlled by electrical field using copper wire electrode inserted in the low refractive index – transparency polishing pad. As results, we can be observe the movement of the diamond particle between the pattern structures under the pad by electrical field using digital microscope.

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In polishing of aspherical lens shape or a large diameter reflecting mirror such as astronomical observatory, "a small tool" is used, which is smaller than the workpiece. Since small tools have low polishing efficiency, we propose a novel polishing method that leads to enhanced removal rate using AC electric field. In this paper, we report a result to polish a silicon wafer with the prototype small tool of this polishing method.

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Chemical-Mechanical-Polishing (CMP) is one of the methods for polishing silicon wafer edge. However, conventional CMP using loose abrasive causes edge roll-off and deteriorate shape accuracy. Therefore, a novel CMP polishing method using ultrasonic vibration is proposed for silicon wafer edge. The experimental equipment, which has a polishing device equipped with six ultrasonic units composed of an ultrasonic spindle enabling polishing three surfaces of silicon wafer edge (upper bevel, apex and lower bevel) at the same time, was designed and fabricated in previous study. In this study, high efficiency polishing of Si wafer edge by two steps of forming process and final polishing process is reported.

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In ultra-precision machining field, it is gradually increasing a demand to manage both machining efficiency and accuracy. To achieve high machining efficiency, each axis has to move at high speed. Though, it can cause travelling error due to servo delay regarding the acceleration/deceleration after interpolation processing. This makes machining accuracy worse especially in machining of free-form shape. This study proposes a way of tool-path optimization which applies compensation for servo delay to improve machining accuracy and efficiency.

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In this paper, an influence of difference in work material on diamond tool wear in elliptical vibration cutting is discussed. Pure iron, carbon steel and martensitic stainless steel were chosen as work material to investigate influences of carbon contents and alloy element. Ultrasonic vibration cutting tests were carried out both in the atmosphere and vacuum environment. Only in the stainless steel cutting, large wear amount was measured and signature of significant chromium carbide formation was obtained by TOF-SIMS analysis.

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We have developed an automated three-dimensional information acquisition system based on consecutive precision cutting and cross-sectional image recording. In previous report, micro Vickers indentation tests were conducted at regular intervals in image recording process and the micro hardness distribution measurements of steels were performed in high-precision consecutive cutting and observation. However, the interval was 70 μm because indentation depth was almost 5 μm. In this study, on-machine measurement of micro hardness less than depth of 1 μm was examined using a micro force sensor, a piezo stage, and a Berkovich indenter.

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Scraping is manual finishing process for machined surface to obtain an ultra-high precision surface. Machined surface is shaved off by a thickness of a few micrometers from the surface with a manual tool like a flat surfaced chisel. The high level skill of expert is necessary to reduce a processing time and a processing cost required for scraping. This study evaluates skill levels of workers by measuring the processing force that a scraper gives to a workpiece during the scraping work. To scrape off necessary quantity exactly and efficiently, it is necessary to add force to the tool so that the cutting edge draws a circle. Therefore, it is necessary to synchronize a force to push the cutting edge forward and a force to push the edge downward. This study shows that the skill levels of workers can be evaluated to quantify a sense of rhythm of worker from a force waveform.

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The properties of TiN films deposited by Arc Ion Plating (AIP) and Ion Beam Assisted Deposition (IBAD) method was studied to improve adhesion strength of the film. A cold work tool steel, SKD11, was used for a substrate. The substrates were coated with TiN by AIP and IBAD process. These coatings carried out at relatively low temperatures of approximately 773K. The microstructure and crystal orientation for the TiN coatings were investigated by Scanning electron microscope (SEM) and X-ray diffraction (XRD). Adhesions of the TiN coatings were evaluated using a Rockwell indentation tester. The TiN-IBAD coating had a mixed orientation of (111), (200), (220) and (222). The TiN-AIP coating with a very strong (111) orientation shows a high hardness.

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The c- or β-C₃N₄ phase in the amorphous carbon matrix has been obtained by low energy nitrogen implantation into graphite and unbalanced magnetron sputtering. These results indicate that ion impact is important for the growth of super-hard carbon nitride. It is important to clarify the effect of ion impact on the growth of crystalline carbon nitride for the synthesis of super-hard carbon nitride. In this study, we investigated the structure and composition of carbon nitride film prepared using g-C₃N₄ as an evaporation source for ion-beam-assisted deposition. Carbon nitride was deposited by ion beam assisted deposition. The graphitic carbon nitride as an evaporates source is obtained by heating the melamine at 550℃, and then it was formed pellet by press molding. The film was obtained by the evaporation using the pellet molded at 200℃ as the evaporation source. The films contained the carbon and nitrogen were obtained by ion beam assisted deposition from g-C₃N₄ evaporation source. In addition, it was suggested that the C-N bond formation in the deposits can be easily obtained using the g-C₃N₄ in comparison with graphite.

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To improve the performance of magnetic drive torque actuator that consists of a superelastic material and a ferromagnetic material, it is necessary to increase the operation torque, and to reduce the gradient of torque in a superelastic region. The structure of the composite material which consisted of soft iron and superelastic wires were examined by the FEM analysis. To increase the operation torque, the superelastic wires were arranged in two rows. As a result of the FEM analysis, the operation torque when the superelastic wires are arranged in two rows compared with the case arranged in a row has increased greatly. Furthermore, it became clear to be able to decrease a gradient of torque by increasing the number of superelastic wires of the inside row than an outside row. In addition, we carried out the analysis that the number of superelastic wires changed in the longer direction of the composite. In conclusion, the operation torque decreased by gradually increasing the number of superelastic wires from the revolving shaft side towards a peripheral side, but it became clear to be able to decrease a gradient of torque.

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Wasted tubes from a nuclear power plant must be axially split without generating by-products in order to assess the radioactive contamination before disposition. In this research, cutting method using a driven rotary tool was attempted to apply to it, following our previous study of radial-direction cutting. The cutting behavior with plastic deformation was examined in plate and tube specimens. It was essential that a material pushed out by a tool edge flows perpendicular to the cutting direction and does not bulge outwards.

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When the fracture splitting method is applied to aluminum alloy die-cast connecting rod, the ruggedness on the splitted surface may crash while driving the engine. A fatigue endurance test was conducted by repeatedly applying a load to a connecting rod fabricated by the fractured splitting method. That was investigated whether it could be safely used during driving the engine. As a result, when the load amplitude was severer than the actual working load, the connecting rod ruptured from the small end of the connecting rod before crushing occurred on the splitted surface. There was also a trace like rubbing on the splitted surface. As a result of FEM analysis, it was found that if the load does not exceed the driving load, there is no gap between the splitted surfaces and aluminum alloy die-cast connecting rod can be safely used.

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There is a possibility that the roundness of the big end hole changes when the fracture splitting method is applied to the aluminum alloy die-cast connecting rod. In this study, it is examined by FEM analysis whether the roundness of the big end hole is kept by tightening the bolt after the process of the fracture splitting. As a result of the analysis, the big end hole was axially extended with the plastic deformation by the fracture splitting process. In addition, it became clear that the connecting rod was deformed by the bolting in elasticity and the big end hole shortened axially. As a result, the possibility that the fracture splitting method was able to be applied to the aluminum alloy die-cast connecting rod was shown.

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Friction welding method was applied to improve the productivity in manufacturing for a dissimilar pipe joint. In this research, a joining experiment for using a circular pipe of A5052 Al alloy and SUS304 stainless steel was conducted and the effects of the welding condition on the joining phenomena and the joint strength were investigated. Even if the thickness changes, good joints with fracture on the A5052 side are obtained by setting suitable friction welding conditions.

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Linear friction welding machine with simple components system was developed to join the square members. Reciprocating motion of linear friction welding was produced by two cams which were placed on outsides of specimen chucking vice. It was found that this machine was able to perform linear friction welding when the experiments of joining pure aluminum were carried out by changing the friction pressures variously.

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The formability of corrugated cup was investigated by deep drawing process using roller die. To form the corrugated shape on side wall, the bearing balls were set on the shoulder of a die. In addition, the balls rotate freely during forming. The test material was a rolled thin plate of commercially extra-low carbon steel SPCC 0.3 to 0.5 mm, punched out to a diameter of 85 mm. The deep drawing process was performed using an oil hydraulic press. The bearing balls were tool steel SUJ2 with a diameter of 10 mm or less. The lubricant used was the solid powders of molybdenum disulfide. The metal sheets were successfully drawn without the cracks. It was found that the corrugated cup having small wave shape was successfully formed by using the roller die.

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The formability of the laminated sheets was investigated to control the ears in the deep drawn cup. Planar anisotropy causes ears to form in drawn cups. To control the occurrence of the ears, the deep drawing of the laminated sheet in consideration of anisotropy was carried out. In the experiment, the blank was pure titanium JIS1 and pure aluminum A1050. The initial thickness of the sheet was 0.5 mm. The blank diameter was 70 mm. The laminated sheets were constituted in two sheets. Two sheets were located in the direction where varied in a rolling direction. Lubricant was also applied alumina powder on the contact planes of sheets. A punch diameter is 40 mm, and the drawing ratio is about 1.7. The clearance between the punch and die was set to be equal to the thickness of the laminated sheets. For the prevention of seizure in contact area between a drawing tool and blank, Teflon (Polytetrafluoroethylene, PTFE) is used as lubricant. The number of ears produced were four. When it was located in the 45-degree direction for a rolling direction, the ears of the drawn cup were controlled most. In addition, the height of the ears decreased with increasing surface roughness and blank holder force.

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Deep drawing is a process for making a seamless hollow there dimensional cup from a single blank. Cups made by deep drawing are used in various field such as living goods such as aluminum cans and industrial goods such as automobile parts. Therefore, improvement of the cup itself is required. We attempted to form a corrugated cup with a wave shape on the side wall by using a mold in which hard steel balls were arranged without gaps in the shoulder of the die. The blanks were commercially extra-low carbon steel SPCC. The initial diameter and thickness of blank are 70 to 95 mm and 0.5 mm. The metal sheets were successfully drawn without the cracks. It was found that the corrugated cups were successfully formed by using the roller die.

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The formability of the rectangular cup by deep drawing process was investigated, to expand the functionality of the titanium drawn cup,. Forming of titanium sheet was tried by multistage deep drawing. In the experiment, the material was pure titanium sheets of the JIS grade 2. The initial thickness of the blank was 0.5mm in thickness. For the prevention, pure titanium sheets were treated by heat oxide coating. The effect of the plastic anisotropic on the occurrence of seizure in square cup deep drawing was also examined. The square cups were successfully drawn by heat oxide coating. The coating of titanium sheet has sufficient ability in preventing the seizure in multistage deep drawing operation. It was found that the square titanium cups were successfully formed by using heat oxide coating treatment.

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The Formability of titanium alloy sheet in the multistage deep drawing was investigated. In the titanium alloys, the beta titanium alloys have good cold workability in the metal forming. However, a seizure tends to occur during metal forming due to high reactivity with other metals. In this study, to improve the formability of titanium alloy sheet, the formability in multistage deep drawing process of beta titanium alloy was investigated. The blank used was the commercial beta titanium alloy Ti-15V-3Cr-3Sn-3Al. To prevent the occurrence of seizure, the blank treated by oxide heating was used. The effects of the surface roughness and hardness on the formability in the multistage deep drawing processes were examined. The improvement of surface roughness of drawn cup was also attempted by using heat treatment. A long titanium alloy cup was successfully formed by intermediate annealing at the 3rd stage. It was found that the drawn cup by multistage deep drawing could be formed to the 6th stage.

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