Hobbing is an efficient method to manufacture high quality gear. It is difficult to understand the hobbing mechanism. So there were some researches of hob cutter wear using a flytool. However in these researches, V shape grove were produced which is not an actual gear shape. In this study, new experimental method is proposed. New experimental apparatus was developed. Blank material was cut with a single cutter using a horizontal milling machine. The blank material was moved by a linear slider and a rotational motor. This gear shape was an actual gear shape with involute. The relation between the tool wear and the cutting distance was investigated in this method. And the chip formation was observed.

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Dry hobbing, which is a gear processing method wihout cutting oils, is useful for cutting cost and reducing environmental pollution. However, the dry hobbing has problems, for example, increase of the cutting temperature, cutting surface damage by the chips, and so on. This study produces a new gear processing method for dry hobbing. The method, "a vibration dry hobbing", gives axial micro vibration to a rotating hob. The vibration is provided by an oscillator. This paper explains the structure of the vibration hobbing machine which we developed, and shows the effectiveness of the machine by using experimental results. The vibration dry hobbing mehod was carried out for the HRC55 materials as finish machining under the following conditions : the cutting depth is 0.34 mm, the hob frequency is 1,034 Hz, the hob total amplitude is about 5μm, the cutting speed is 40.8m/min, the feed rate of hob is 1.0mm/rev and the hob module is 1.75. As the result, the black chips were changed into the white chips by the vibration. This result shows that the vibration dry hobbing method reduces the friction between hob and work, and decreases the processing temperature.

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Whiling is applied to helical plate machining with controlling the spindle speeds of the workpiece and the tool. When the ratio of the tool spindle speed to the workpiece one is 2, a plate type blade is machined. Then, a helical blade is machined with changing the ratio a little and feeding the tools in the direction of the workpiece axis. A mechanistic model is presented to simulate the machining shapes with the edges motions during machining. The machining shapes and the surface finishes were measured by a coordinate measuring machine. The curvature of the plains on the blade decreases with the rotation radius of the tools; the blade thickness becomes large at the end of the workpiece due to workpiece displacement; and the surface finish around the center is better than the side of the blade.

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One of the most critical issues in cutting of ductile metals is chip adhesion to tool surfaces, leading to tool break age and deterioration of finished surface roughness. The present study proposes a novel strategy for removing the adhesion layer from the tool surface and recovering the cutting tool performance without detaching the cutting tool from the machine tool; namely, an on-machine tool resharpening process. To achieve efficient removal of the aluminum adhesion layer from the tool surface, the phenomenon of liquid metal embrittlement (LME), which is defined as a brittle fracture, or loss in ductility, of a ductile material in the presence of a liquid metal is employed. A series of experiments showed that the newly developed strategy employing LME is highly effective in removing the adhesion layer without damage to the tool substrate and has great potential for addressing the issues related to the dry machining of aluminum alloys. In addition, the removal performance of the developed resharpening process for steel materials is discussed.

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In machining of difficult-to-cut materials with end mill, High efficiency machining is difficult because work material have high adhesion and heat resistance. So tool need high adhesion resistance performance. Conventional technologies have a smooth coating surface with polish of blast, but this technology is damaged to the cutting edge. SMART MIRACLE has new surface treatment technology, what can realize smooth surface with keeping sharp cutting edge. SMART MIRACLE achieves 3 times efficiency of conventional with developed coat and geometry.

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Recently, high-combustion-efficiency jet engines have become required in the aircraft industry. High burning temperatures are necessary to maximize the combustion efficiency of jet engines. Inconel 718, which has excellent mechanical and chemical properties, has been selected for use in many jet engine parts. However, Inconel 718 is a difficult material to cut because of its low thermal conductivity. Consequently, wet cutting is typically used to reduce the heat generated in cutting Inconel 718. In this report, we experimentally examined the tool wear characteristics of cemented carbide tool.

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For better selection of coated cutting tools, TiAlN (Ti50Al50N) and CrAlN (Cr50Al50N) coatings were deposited onto ball-nose and square end mills using arc evaporation, and their cutting performances were evaluated using steel workpieces of various hardnesses. In particular, cutting tests were performed on three types of workpieces, made from S50C, SKD61, and SKD11 steels, having Brinell hardness numbers of HB220, HRC40, and HRC60, respectively. The results of the cutting experiments were elucidated and discussed in terms of the mechanical properties and anti-oxidation resistances of the different coatings. The results revealed that TiAlN-coated square end mills at high cutting speeds (V=200 m/min) had superior performance when used on steels with high hardness, whereas CrAlN-coated ball-nose end mills were superior when used on low hardness steel. Therefore, CrAlN-coated ball-nose end mills are concluded to be suitable for the machining of low hardness steels, whereas TiAlN-coated square end mills are preferable for the machining of high hardness steels.

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The paper discusses tool wear characteristics in drilling of CFRP stacked on Ti-6Al-4V. A cutting simulation was applied to prediction of the cutting force, the cutting temperature and the tool wear. The flank wear progress on the end of the lips, which finish the surface in the hole, was measured in the cutting tests. The wear characteristic constants in the tool wear model were identified to minimize the prediction error in the cutting simulation. Based on the wear characteristic constants, the control factor in the flank wear progress is discussed. The flank wear progress of CFRP largely depends on the stress with abrasive effect; while, the wear in drilling of Ti alloy is sensitive to the temperature.

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This research focuses on machining error due to the workpiece elastic deformation and investigates the influence on the machining error. Orthogonal cuttings by a straight edge end-mill of the elastomers are carried out. Displacements of workpiece during processing are measured by using a high speed camera. Furthermore, workpiece surface is measured by the scanning laser displacement sensor. Influence of cutting condition on the machining error and the workpiece elastic deformation is investigated by comparing the relationship between the deformation and the machining error.

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This paper studies the deformation of a thin wall during milling process. First, cutting experiments are presented to investigate the influence of the workpiece thickness on its deformation and the cutting force. Then, this paper presents a FEM-based model to simulate the deformation of thin-wall workpiece during milling process. With a tool rotation, cutting force is distributed along the helical cutting edge, and the workpiece deformation is calculated at each time interval with tool rotation. The simulated result is compared with a simpler model where a constant cutting force is uniformly distributed on an oblique line representing the material removal by a cylindrical tool.

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Micro cutting technology is one of the important methods to fabricate micro-sized precision components in the semiconductor, electronics, and electro-mechanics industries. However, high productivity and high precision machining is difficult, because a micro end-mill has a very low strength and stiffness. Therefore, there is a cutting force measurement as one method to solve this problem. In this paper, position errors, one of the geometric errors of a groove for an epoxy/glass laminated substrate are discussed experimentally during full tool-width milling using a high frequency response dynamometer. As a result, the cutting force becomes large in a glass part. In addition, the difference of the cutting force between epoxy parts and glass parts become small when feed rate is large.

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A flexible circular saw, which can be used in a novel machining process for high-speed carbon fiber-reinforced plastic (CFRP) cutting, was developed. This process can carry out high-speed curved-line cutting with a feed rate of 3 m/min. However, the minimum radius of the target curve that can be cut by this process was limited to larger than R3200 mm. It couldn't meet the demand for small radius curves. In this research, in order to apply to small products, micro sawing machine for flexible circular saw was developed. The minimum radius of the target curve depends on the diameter of the saw. The micro saw with the diameter of 50 mm can realize the radius of R205 mm. Then, the feasibility test of the micro saw was carried out.

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Recently, radius end mills have been developed to machine highly accurate and efficient three-dimensional shapes. But the cutting edge shape is complex and there are few papers that focus on the radius end mill. Therefore, in this paper we geometrically analyze the theoretical roughness for inclined surface with the scanning method. At first, the equation for theoretical roughness is shown. Secondly, the surface roughness is measured by cutting tests and compared with the experimental results. Finally, it is shown that the estimated values of the theoretical roughness are almost coincident to the experimental values and analytical method for calculating the estimated theoretical roughness is highly accurate.

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Microchannel chips used in micro total analysis systems are attracting attention in the medical field. The photolithography technology used in semiconductor manufacturing is generally used to manufacture microchannel chip dies. However, this technology requires many processes, such as mask fabrication and the application of photoresist to a substrate, as well as expensive clean room facilities. So, this study examins how to form a fine groove by cutting with micro endmills. This report experimentally examined cutting performance of tool run-out. As a result, effect of tool run-out on micro endmilling, such as decreasing cutting force was clarified.

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Recently, increasingly high efficiency and high performance have become to be required of information equipment. As a result, optical scanning parts that reduce optical aberrations, scatter, and diffraction are required in laser printers. It is therefore necessary to improve the geometric surface roughness achieved in mirror cutting of Al alloys and eliminate tear-out marks and scratch marks that can be created during the cutting process. In this study, we investigated the effect of feed speed on the occurrence of surface discontinuities in ultra-precision cutting of Al alloys.

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The large deformation that occurs while the turbine blades of forged material are machined, with another generation of the chatter vibration, are an embarrassing problem for turbine blades manufacturer like us, and what is more, appropriate information on this field is few. Then we decided to look for the solution experimentally considering such a current state. In the experiment, the influence level was examined about various factors on the cutting resistance. As one of the results, it has been understood that the number of cutting teeth of the tool greatly influences the machining accuracy.

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Fluctuation in the chip flow velocity on the tool with time affects heat generation on the rake face of the tool, tool temperature, tool wear, tool life and surface quality of the workpiece. In the conventional cutting theories, chip flow velocity is assumed to be constant under constant cutting speed. Although a considerable number of studies on the cutting force have been made over the past decades, there have been little studies that tried to observe the chip flow velocity with time. This paper evaluates the effect on thermal fatigue of tool of the fluctuations of chip flow velocity and the cutting force through cutting experiments with a high speed camera and tool dynamometer. Changes of tool temperature and stress distribution during very short time, which are considered to have significant effects on the tool wear mechanism, are also quantitatively analyzed by finite element method.

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Recently, β-type titanium alloy exhibiting super-elasticity and super-plasticity was developed. The excellent characteristics of this alloy indicate its likely application in the field of oral surgery. However, super-elasto-plastic titanium alloy is difficult to cut because of its high adherence and low thermal conductivity. In this study, the effect of tool coating on the tool life and surface roughness were investigated in milling of super-elasto-plastic titanium alloy with a small ball end mill tool. Tool life of AlCrSiN coated tool is longer than TiSiN coated tool and DLC coated tool. The tool wear progress of TiSiN coated tool with flaking. The thickness of DLC coating film is thinner than that of AlCrSiN coated tool. Therefore, the flank wear of DLC coated tool was large. On the other hand, the surface roughness of AlCrSiN coated tool is approximately 2.0 μm in initial cutting. However, it becomes less than 0.8μmRz with increasing cutting length. Thus, AlCrSiN coated tool is expected in view of the tool life and surface roughness.

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High-efficiency and high-precision machining technique of the Ni-based heat resistant alloy like Inconel 718 is important concern in the aviation industry. The study deals with the turning of Inconel 718 with SiAlON ceramics and polycrystalline cubic boron nitride (PCBN) tools in the cutting speed range from 200 to 400 m/min. The PCBN tool, which is made of cBN and new ceramic binder, have long tool-life with good surface integrity compared with SiAlON ceramics and conventional PCBN, because of the advantage in terms of its mechanical properties and low-affinity to heat resistant alloy.

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This paper deals with the cutting mechanism of cemented carbide by using a diamond coated carbide end mill. Geometry of the chips, tool wear behavior, and machined groove integrity were investigated experimentally. R3 ball end mill was applied under supplying air blow. As a results, saw-tooth type chips were generated even in the cemented carbide cutting. The diamond coated tool was fractured when the groove length was 80 to 100 mm in the high feed rate (f=30 μm/tooth). The width of machined groove decreased with the flaking of the coating film on the bottom flank face.

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An abrasion resistance, heat damage resistance and hardness of cemented carbide are better than high hardened steels. Therefore cemented carbide is expected for die and mold. But cutting of cemented carbide is quite difficult by carbide tool. So we usualy cut cemented carbide by diamond tool. For instance, PCD tool is used for surface finishing. Although cutting edge of PCD square end mill is brittle. Therefore we developed high stiffness cutting edge of PCD square end mill. We obtain sharp coner and exellent surface by using developed PCD square end mill, and achieve longer tool life with arc shaped cutting edges.

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In this paper, the influences of the protrusion length of tool on the dynamic characteristics of the spindle system are examined experimentally based on the impulse response method. From the experimental results, the following are clarified: In case of shorter tool protrusion, the compliance of primary vibration mode of the spindle system is proportional to 3rd power of protrusion length likely to cantilever bending. In case of the length over the critical length, the compliance remarkably increases, and then, it becomes proportional to 6th power of the length. Such remarkable increase indicates that the vibrational of chuck body cannot be neglected. The critical protrusion length and the compliance increasing characteristics vary corresponding to the type and mechanism of chucks.

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We propose the smart test-tool using strain gauges for evaluating and measuring the distribution of tool chucking force. The configurations of the smart test-tool determined by finite element method and experiments have been carried out to create a prototype. As a result, the following conclusions were obtained: The strain gauges fitting multi points in axial direction make the smart test-tool determine the distribution of tool chucking force. The chucking force distribution can be identified from the continuous strain distribution determined by spline interpolation of measured strains at 5 discrete points. The measured results of the smart test-tool indicate that the nearer the chuck exit the stronger chucking force acts in case of collet chuck.

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FEM simulation for the cutting of Ti-6Al-4V alloy was investigated. As for the constitutive law, the Johnson-Cook model that applied a reported parameters by Meyer-Kleponis was used. At the first, the calculated results were compared with the results of the cutting test such as the cutting force, cutting temperature and shape of chips. The calculated results for the cutting force, cutting temperature and the shape of chips nearly corresponded with the experimental results. The second, the cutting test using the restricted tools which reduced cutting force by shortening the contact length of the rake face of the tool and the chips was carried out. The cutting force was decreased as approximately 10%. These results showed that the computer simulation was effective for the design of the tool shape.

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In the present report, we focus on finishing of bottom surface on micro channel by magnetic polishing process with a ball-nose-shaped tool. The end milling and polishing processes were integrated with a desktop-sized machine tool. We investigated influences of polishing conditions on the amount of polishing, surface roughness, and mirror state for various groove shapes. Polishing condition for groove shape was determined based on experimental results on plane surface polishing. We implemented some experiments to evaluate influences of the condition on polishing effects of grooves. A proper polishing condition was derived from the experiments.

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Minimal quantity lubrication (MQL) machining has so far been recognized as a representative near-dry machining operation and it has demonstrated successful results in a number of practical applications, becoming common technology mainly for machining of steels. Recent concern for environmentally friendly manufacturing further encourages the attempts at applying the MQL operation to machining of difficult-to-cut materials. Since titanium alloys are typical difficult-to-cut materials, this paper investigates the cutting performance of MQL methods in turning of a titanium alloy from the view point of elongating the tool life. As a MQL lubricant, the investigation uses such oxygen-including compounds as a synthetic polyol ester, which presents the successful cutting performance for MQL machining of steels, oleyl alcohol and oleic acid. The MQL operations have provided considerably long tool life compared with that of dry machining and oleyl alcohol has demonstrated the excellent cutting performance particularly at the small depth of cut.

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This paper deals with the influence of various coating films of high-speed steel tool on tool life (flank wear) in hobbing with dry cutting and minimal quantity lubrication (MQL) system when changing the hob feed. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The results are summarized as follows. (1) In the case of hob feed of 1.5 mm/rev, TiN-coated tool is effective for dry cutting and AlCrSiN-coated tool is effective for MQL system. (2) With 4.0 mm/rev, TiSiN-coated tool is suitable for dry cutting and TiAlN and AlCrSiN-coated tools are suitable for MQL system. Especially, an AlCrSiN-coated tool showed the tool life obtained with MQL system more than twelve times compared with dry cutting.

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This paper deals with the influence of cutting speed and feed rate on tool wear in the end milling of CFRP. As a result, in dry cutting, the tool life increases with decreasing the cutting speed, and the cutting speed of 69 m/min is suitable. The tool life obtained with the feed rate of 100 mm/min is longer than that obtained with 200 mm/min. It was found that the supply of water as a cutting fluid prolongs the tool life at a high cutting speed of 126 m/min, although the water is ineffective at the cutting speeds of 69 and 93 m/min.

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Oil with an effective chlorinated extremely pressure additive (EP-additive) has widely used for severe metal forming like ironing of stainless steel, because this chloride-oil is superior to the chloride-free oil in an anti-galling property. Environmental and safety issues, however, demands to replace this chloride-oil by chloride-free oil. Particularly, higher performance chloride-free oil is strongly required for ironing of stainless steel. In this paper, the anti-galling performance of oil with organic-sulfur has estimated by an inner-cup ironing test to develop high performance chloride free oil. Furthermore, a series of tests with 10,000-shots ironing in manufacturing showed that the developed oil is as excellent as the conventional chloride oil.

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In recent years, there are various ways of determining the cutting conditions. In this study, we focused on the cutting sound. Peripheral turning of carbon steel (C0.45%) by using a lathe were carried out in order to examine relationship between tool wear and waveform. Characteristic signals were extracted by FFT analysis of the waveform. As a result, it was found that the sound pressure of a specific frequency range is increased during cutting process. Moreover, sound pressure rise factor on the hypothesis; (1) frictional sound of the tool flank (2) frictional sound of the tool rake face (3) Sound from the shear deformation. We considered the generation mechanism of cutting sound.

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In cutting process, cutting condition has a strong effect on tool life and machining speed. It is required that high production system which balances tool life and production efficiency in factories. In this study, we focused on heat energy generated by cutting as the cause of tool wear. In order to equalize a cutting energy, cutting tests which at a certain material removal rate and wear mode of tool was estimated. In addition, two dimensional cutting was performed to calculate cutting energies. Furthermore, cutting temperature in each condition was measured by tool-work thermocouple measurement. At the these results, we clarified the correlation between the tool wear and cutting temperature and consider the effective search method for an optimum cutting condition.

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In order to alternate a high precision grinding of hardened steel with high precision cutting, it is proposed to form cutting edge of a CBN tool by using a nanosecond pulse laser. However, in order to process the components with good shape accuracy, it is necessary to suppress tool wear. In this paper, ultra-precision cutting experiments of hardened steel with coating CBN tools was carried out, and its tool wear was verified. As a result, coating CBN tools were able to suppress the flank wear. And surface roughness was smallest BNC 100 as compared to BN2000 and BNC200.

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A reduction in cutting force achieved by using the textured tools was confirmed even under dry conditions. The results of orthogonal cutting tests for carbon steel with non-textured and micro textured tools indicated that both of cutting force components definitely reduces through reduction in tool-chip contact length at cutting speeds higher than 150 m/min. In addition, tests employing various textured tools suggested that effective textures possess ridged patterns perpendicular to the chip flow direction. Moreover, from results of the tests using tools with sectionally textured surfaces, it was revealed that the textures located at an area where friction state changes from adhesion friction to sliding one bring about the cutting force reduction.

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Powder jet deposition (PJD) is a coating process through the use of high speed particle impact. The authors have proposed a new dental treatment method by using this process with hydroxyapatite (HA) powder, which accomplishes cavity protection, caries prevention, and tooth color improvement. The coating principle of PJD is accumulation of chemical bonds among impacted particles. Hence it is estimated that the fractured HA particle crystal architecture affects the deposition property. In this study, PJD coating experiments were conducted with two kinds of HA particles. It is found that the mechanical strength of the formed films depends on the density of the chemical bonds among the crystal grain boundaries in the films and HA particles suited for PJD can be designed with the control of the powder thermal treatment condition.

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Various functions can be adapted to a surface by depositing functional materials as well as applying micro-structure. However, general methodology to obtain specified functions has not been established. This research demonstrates such functionalization as abrasive tool, light transmittance, heat dissipation, antibacterial function, and piezoelectric functions. Finally, functional design methodology is discussed.

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This study introduces laser-assisted roller nanoimprinting of light-excitation films for flat illumination devices or flexible displays. In the laser-assisted roller nanoimprinting, the mold surface is directly heated by laser irradiation and the structures of mold are thermally replicated on thermoplastic polymer films. The conventional roller nanoimprinting method in which the whole mold is heated causes losing the shape of replicated patterns because the heat remains in the polymer after demolded. In order to prevent from the shape losing, we have proposed the thermal roller nanoimprinting with the mold surface heated by laser-scanning. On the other hand, a flat illumination device of an organic light-emitted diode (OLED) has interesting properties such as flexible, eye friendly, and energy saving. A microscale concave-and-convex surface with the lens array enhances the light emission from the light source because the ratio of the total reflection to inside can be reduced. The roller imprinting is useful for mass production of the large-area light-excitation film because of the low-cost setup, high-throughput, and continuous process.

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This present study fabricates an array of micro-beams by transfer-print of Au thin-film on a micro-ridged substrate. The production yield of micro-beam is strongly affected by the surface properties of thin-film on the stamp. A hydrophobic surface of h-PDMS stamp allows Au thin-film to have surface asperities with tens nanometer in height, so that it enables the thin-film to be easily released from the stamp. Higher production yield of micro-beam can be achieved by transfer print of a multi-layered thin-film, which is composed by vapor-deposited Au and sputtered Cu and Al. A surface modification of Au thin-film, which is covered with 4-mercaptopropionic acid self-assembled monolayer, also improves the production yield of micro-beams fabricated by transfer-print because of an enhancement of adhesion force to the substrate.

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A new fabrication method for realizing ordered nanopillar array is developed. In this method, firstly, a nanodot array is fabricated by combination of Nano Plastic Forming (NPF) and thermal dewetting, which does not involve costly and complicated processes such as EB-lithography. Then the Au-capped nanopillar arrays are produced by reactive ion etching (RIE). Finally, an Ag film is deposited on the nanopillar array. It is found the nanopillar arrays with Ag coating show good performance as a surface-enhanced Raman scattering (SERS)-active substrate.

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