Restraint of burr and deburring are important problems for the establishment of fine machining technology to the austenite stainless steel. Basic investigations are conducted in this study in order to resolve these problems. Formation conditions are examined by cutting of SUS304, and the comparisons of hardness distributions on formed burr and the results of cutting simulations by non-linear finite element method are carried out in this report. As the results, it is not able to completely restrain the burr however the undeformed chip thickness is decreased, and the good agreements are analyzed between the distributions of equivalent plastic strain and the distributions of hardness on burr.

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The effect of cutting fluids on the brittle-ductile transition in micro ball end milling is investigated as a basic study for efficient fabrication of micro structure of brittle materials. Because material removal process with a ball end mill varies widely with tool tilt angles, the effect of tool tilt angles on the transition is also examined. The workpiece is borosilicate glass. As a result, it is found that the critical depth of cut, at which the brittle-ductile transition occurs, increases with the tool tilt angle if the angle causes down milling. It is also found that cutting fluids have a significant but sophisticated effect on the transition.

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

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The in-process measurement method of the temperature distribution on the tool rake face including tool-chip contact area is established. The micro regions temperatures of the tool rake face are measured simultaneously by the Nickel and Nickel(80wt%)-Chromium(20wt%) thin film thermocouples(TFTs). Three types of the tool inserts with built-in TFTs were developed and the cutting temperature experiment was carried out. In this paper, the principle of the measurement and the calibration methods are shown. The sensitivity and response of the TFTs are investigated and the comparison between experimental results and the results of the numerical simulation are discussed.

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MQL cutting was applied to finish-turning of a nickel-base superalloy, Inconel 718. When turning a bar of Inconel 718 with CVD TiCN/Al₂O₃/TiN coated carbide inserts at a cutting speed of 1.0 m/s, tool life in MQL cutting was the same as that in wet cutting. When measuring the surface finish obtained at a cutting speed of 1.0 m/s, the surface finish in MQL cutting was the best. When changing the pressure of the air supply from 0.3MPa to 0.6MPa, tool life of 0.4MPa was longer than both at 0.3MPa and 0.6MPa. When the cutting speed was increased to 1.5 m/s, the tool life by MQL decreased drastically.

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The minute parts cutting technology with nano-order accuracy has been developed and used for producing the high precision parts like fresnel lens, prism and non-spherical lens. In these case, the high machinery material like oxygen-free copper and injection technology are commonly used. In order to improve the productivity of injection, the steal materials should be used for the molds and dies materials. In this sturdy, non-rotational cutting method applied the ultrasonic vibration method has been developed to realize the diamond mentioned above. Single crystal diamond tools can be used for mirror finishing and micro cutting the steal materials. These experimental results show the possibility of manufacturing the metal molds and dies for high precisions parts molding like optical components with high productivity.

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The titanium alloy which has low thermal conductivity causes the tool wear, because the cutting heat concentrates on the tool tip. The purpose of this study is to decrease the tool wear and to realize the dry cutting of the titanium alloy by ultrasonic vibration. Cutting conditions were optimized using the combination of a cutting simulation software and parameter design method in quality engineering. Ultrasonic vibration cutting tests of titanium alloy were conducted without cutting fluid. The cutting force and the tool wear were evaluated.

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Recently, a lot of attention was given on the cutting of hard and rigid material precision parts. Since it is a brittle material, conventional processing method is not applicable and a different processing method is needed. Among the most advantages method is to use the vibration cutting method. This study reports the experiment done on the use of twist ultrasonic vibration cutting method on the hard and rigid of material of precision parts.

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This paper deals with the fabrication of micro flat drills with a diameter of 7 μm by precision grinding and their application to micro drilling into duralumin with or without ultrasonic vibration. Micro flat drills were made of ultra-fine grained cemented carbide which contained WC particles with a diameter of 90 nm. The drills with thick or thin web were used in the drilling test. The life of the drill in the drilling with ultrasonic vibration was shorter than that in the conventional drilling under the condition of using drills with thin web. On the other hand the life of the drill in the drilling with ultrasonic vibration was longer than that in the conventional drilling under the condition of using drills with thick web. With the drill which had thick web and with ultrasonic vibration it was possible to make the most holes in this experiment.

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Diamond tools have superior characteristics such as high hardness, high thermal conductivity and others. But the diamond tool is not suitable for grinding of steels because diamond is worn out due to heat chemical reactions with steels during grinding process. In this study, high precision grinding for die steels that uses electro-deposited diamond tool with 60kHz longitudinal ultrasonic vibration was tried to avoid manual finishing of die. And grinded surfaces and tool wears were measured, and practicality of ultrasonic grinding for die steels was evaluated.

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The present paper deals with the fabrication conditions - current density, electroplating time and grit diameter - of Ni-W electroplated micro diamond tools with a diameter of 100 μm and the grooving characteristics - tool life and machining accuracy - into silicon without and with ultrasonic vibration.

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High-speed and low-cost texturing technology is required in various fields. It is already known that fine ductile micromachining of brittle material such as glass is possible with ultrasonic vibration tool if the depth of cut is small. Applying horizontal vibration (70-280Hz) to the vibrated tiny tool, surface micro texturing, as transcription of the horizontal tool locus, is expected. This paper demonstrates the texturing on glass surface with multi-axes vibration tool (f0.1mm), and effects of tool shape and frequency of tool vibration on machined groove are made clear.

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A polishing system assisted by the ultrasonic vibration has been studied. A felt buff is attached on the polishing tool top and loose abrasives in slurry are supplied there. The polishing tool can be rotated independent with the ultrasonic movement. Some different conditions have been applied in experiments, and the polishing process which utilized the elasticity of a fiber was confirmed. It is found that the management of the distance between the workpiece and the tool top is difficult, and the future task has been identified.

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We investigated characteristic of micro-sized holes on hard and brittle materials using ultrasonic machining. However, chippings are generally observed around the edge of the machined micro-holes. It was found that the convergence of abrasive grain around the interface between the tool and the workpiece. It is reason to eliminate chippings. We applied an electrorheological fluid assisted method to a micro ultrasonic machining system. Using electrorheological fluid assist, micro-sized holes′ edge chippings drastically reduced. And we also achieved high aspect ratio micro-sized holes.

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It was confirmed that CVD diamond film could be polished by polishing method without abrasive grain assisted by ultrasonic vibration which generated frictional heat. And it was confirmed that polishing was done smoothly by spreading oil on polishing surface. In this paper the selection of the best polishing condition is discussed by examining surface roughness of CVD diamond film polished by changing tool feed, number of polishing repetition and a tool diameter for improving condition of polished surface.

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Recent researches on machine tools, end mills, machining strategy and end milling process have been surveyed. The latest trend on machine tools is a development of small size high-speed machining center. Its maximum spindle speed reaches 400,000min^-1 and a linear motor type table is employed. On machining strategy, new machining system without NC program is proposed. This system is based on digital copy milling system and CAD data of parts. Furthermore, a chatter prevention system is reported. The characteristics is that cutting condition is automatically modified to a stable condition if the chatter stability of a programmed NC data is unstable. Last, machining errors in ball end milling of spherical surfaces are described.

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Cutting processes with cBN ball end mills are discussed to machine hard materials. Cutting tests are performed to show the maximum depth of cut in grooving with observing the machined surfaces. Some machining examples are shown to use the cBN milling tools in the practical machining operations.

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This paper discusses cutting forces in the milling processes of brittle materials with cBN tool. Micro grooves 20μm deep are machined on cemented carbide and ceramics. Three components of the cutting force are measured with a set of piezo dynamometers. The noise signals induced by the vibration of the fixture, the tool, the spindle and the table are removed with the filters in the frequency domain. The measured cutting forces show that the cutting processes in machining of cemented carbide and ceramics are the same manner as that of machining of metals; and the cutting force also changes with the uncut chip thickness. The cutting area with the cuter rotation is analyzed to show the effect of the tilt of the tool on the actual cutting time. The actual cutting time, which is the time for contacting with the materials, reduces with increasing the tilt angle of the milling tool. It leads to a long tool life with enough cooling in water.

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Fused silica is machined to manufacture micro grooves on micro TASs with ball end mills made of cBN. The tilted ball end mills, whose diameter is 0.4mm, are examined to machine the glasses at a rotational speed of 20,000rpm and in an axial depth of cut of 20μm. Machined surfaces are observed to show the effect of the feed rate and that of the tilt angle of the tool on the cutting processes. The crack free surface can be finished at a feed rate of 0.12mm/min or less. The machined surface is improved by the tilt of the tool because the glass can be machined at a high cutting speed on the edges. The cutting forces are measured with changing the feed rate by a set of piezo electric dynamometers. The noise in the cutting force signal is eliminated by the filtering operation in frequency domain. The cutting force increases with the feed rate though the increasing rate is small.

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In this study, cutting performance of a small-end mill tool in high-speed milling of the austenitic stainless steel (SUS304) was investigated. As a result, the tool life was remarkably improved at a high-speed of 16.7m/s compared with 2.5m/s. In addition, the effect of improvement in smoothness of coated film on tool life was also examined. It is clarified that tool life of coated tool without droplet was twice times in that of commercial coated tool with droplet.

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An exclusive system to generate the surface texture by machining has been developed. However the surface texture pattern created by ball-end milling on any machine tool is always problematic in light of accuracy. We are pleased to propose our approach that could precisely measure the machining accuracy by a scanned type white interferometer. The technique applied in this measurement also allows the precise estimation and analysis of the machining accuracy.

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It is said that reciprocating paths have the advantages for high feed rate machining, compared with spiral paths due to the length of segmented along the tool path. However there is few study about the affects of each path type onto the flank wear and the machined surface roughness. This paper reports the experimental results on the above affects with using small ball end mills of coated cemented carbide and material of SKD-11.

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This paper deals with cutting mechanism and cutting performance of machining for curved surface by a ball end mill. The cutting edge shape of the ball end mill is very complex, so we use 3D-CAD for calculation of chip area during machining with contour line cutter path. The chip area shows transitional phenomenon, but it is shown that the chip area and cutting force are controlled by the looped cutter path method using simulation and cutting test. And also the cutting performance is discussed using the evaluate value calculated by the chip area and the length from Z axis to the gravity of the chip area.

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Measuring system that uses a wire as an electrical contact probe in measuring the form of a ball-end mill on a CNC milling machine is developed in this study. The use of the wire as a line-type stylus rather than as a pin-type stylus, makes it facilitates the reestablishment of the contact point when the stylus generates scratches. Therefore the measurement of the profile of the rotating cutting edge can be continued in spite of wire damage. According the experimental results, form of a rotating ball-end mill can be measured precisely in contact method; the precision of this measuring is 1.9μm in standard deviation.

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In present day, Minimal Quantities of Lubricant (MQL) cutting technology is drawing attention as an environment-friendly cutting technology in the field of metal processing. In order to improve the performance of MQL cutting technology, cutting machine which has the mist through spindle, was developed. In this study, performance of high speed deep hole drilling of this cutting machine was evaluated. In the case of deep hole drilling of aluminum alloy, the effectivity of MQL cutting was shown from the results. Moreover, effective cutting method for deep hole drilling was also proposed.

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This study describes the cutting phenomenon in micro drilling of printed wiring boards(PWBs). This phenomenon is widely noted to be complicated, because the PWBs is composite material. In this paper, the cutting force, drill temperature and workload of drill were measured to make clear the cutting phenomenon. From experimental results, it has been revealed that the margin of drill elastically contact with workpiece in micro drilling and these exists a large frictional heat due to the elastic contact, and especially in the aramid fiber reinforced plastics(AFRP), the frictional heat is longer.

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In order to realize micro hole machining by EDM, minute electrode φ10 micrometers or less fabricate, and final target aim at construction of very minute hole machining technology with a diameter of 1 micrometer or less. The machining scrap metal which comes out when performing minute hole machining becomes the cause of reducing machining efficiency and machining accuracy. If this method is establishable by mass machining of roughing etc., it stops needing the mechanism for circulating processing liquid , and large cost reduction can be aimed at.

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A new multi-functional laser-guided deep-hole boring tool with a 110-mm diameter is fabricated. It can be used for boring, internal grinding and measuring hole accuracies by fixing a head for each purpose on its leading part. Until now, a laser-guided deep-hole boring tool, which is designed for boring, is fabricated and its performance is examined using duralumin (JIS-type 2017-T4) workpieces. As a result, it is found that the tool can be guided to bore a straight hole and be used practically. In the present paper, performance of the new boring tool is examined by using steel (JIS-type S45C) worpieces. Results show that the new tool can be guided to bore a straight hole.

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A new spindle unit has been developed for micro machining based on the non-contact magnetic driving mechanism. It features the on-machine, real-time monitoring of tool revolving synchronization. According to the machining experiments with the developed proto-type spindle unit, a miniature hole of 0.5mm-diameter was machined in a S50C plate with small burr. The conclusion and future studies are briefly mentioned.

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When the drill is overloaded in working with drilling machine, it sometimes breaks or tips out at its edge. This risk must be solved for operator′s safety and economy. We are going to utilize the magnetic mechanism to prevent from the potential break down. In this study, we use permanent magnets for non-contact transmission of torque. Magnets which forms a circular pipe is magnetized in multi-poles along the circle. When magnets are loaded by certain value of torque, each magnetic pole is released from its neighboring poles and it step out. By using this mechanism, the driven axis steps out and cuts off the power transmission when the tool is overloaded and prevent from the potential break down.

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Recently, there is a flow that applies the high hardness material to the metal mold, and the necessity of a new tool and the new processing method has risen. Then, it pays attention to the feature of the cBN tool that began to spread recently (low compatibility to hardness, wear and abrasion resistance, and an iron system material), and it aims at the thing applied to the metal mold processing that uses the system high hardness of iron material. The processing experiment of the cBN tool was done by various processing conditions, therefore an excellent cutting was shown by cutting about the die steel fee of HRC60 or more.

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Milling tests were conducted in order to investigate the cutting performances of a binder-less cBN tool in milling of Ti-15Mo-5Zr-3Al, which was a vanadium-free b type titanium alloy. As a result, compared to Ti-6Al-2Nb-1Ta (a-b type), adhesion and micro chipping were observed both on the rake face and on the flank face , however, high speed milling in cutting speeds of 3.0 – 5.0m/s could be practically performed under the condition of depth of cut of 0.2mm, pick feed of 0.5mm and feed rate of 0.05mm/tooth with a high pressure coolant. Also, it was clarified that the cutting temperature of Ti-15Mo-5Zr-3Al (b type) was higher than that of Ti-6Al-2Nb-1Ta (a-b type).

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Machining tests were carried out on the soft magnetic material using cBN tool at various cutting speed under a constant feed rate and depth of cut. The effect of cutting speed on tool wear was investigated. In the soft magnetic material, the flank wear rate shows minimum value at a cutting speed of 20m/s. However, in high speed machining of the pure iron, flank wear rate is very high in compared with soft magnetic material.

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In tapping, chips jamming in the tap′s flute or twining around the tap cause tool breakage very frequently. In order to resolve this problem, a chip-breaking tool has been developed, which forms grooves axially on the inner wall of hole before tapping. The effectiveness of the new tool has been ascertained in previous reports. On the other hand, the newly tapped thread has axial V-grooves, therefore the female thread may loose the strength. In this report, the strength of two different types of female thread, i.e. conventional thread and V-grooved thread, were compared by experiments. As a result, there was not found any difference between the strength of two types of female thread.

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A tool life detecting system using damage sensor integrated insert for face milling cutter was developed. The system had two resonance circuits. One is a series circuit that consisted of a coil, a capacitor, and an insert in a milling cutter arbor, and the other circuit in a detecting unit. The impedance of the coil in the detecting unit corresponds to substances facing to the coil such as steel part of the arbor, drive keys, and the coil of the circuit in the arbor. The system could detct the signal when the sensor pattern is damaged at the rotational speed of the abor up to 6000 rpm.

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This study deals with the machinability of steels in turning with additional current. Tested work materials were plane carbon steel JIS S45C and BN added steel which has good machinability at high cutting speed. Turning tests were performed by carbide tool P30 in order to investigate the influence of electrical conditions of closed circuit system on the cutting mechanism of BN added steel. The tool life and cutting force was investigated practically and these results were discussed.

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An Engineered Tool was developed to perform high-quality ductile mode grinding of brittle materials, overcoming disadvantages of conventional fine grit grinding wheels. The tool is designed to be used in conjunction with ultrasonic excitation. In this time, single crystal Si was machined by Engineered Tool, using nanometer-resolution machine tool: Robo-nano (Fanuc). As the result, it was found that phase shift of diamond edge sinusoidal motion does not cause any defects such as brittle fractures. And, actual cutting profile was almost equal with calculated cutting edges motion.

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Aiming at establishment of the detailed tool currently used for the detailed processing research in the nano scale in the various fields of engineering in recent years, creation and analysis of the model of a new detailed tool are performed by this research. Comparison and examination with the micro take off lever of a common detailed tool and a creation model were performed, and it inquired for the purpose of the creation of a detailed tool which found out the difference from the conventional thing, the improving point, and the problem, and improved rather than the conventional thing from the result.

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In order to contribute the stabilization of cutting performance of diamond tools, one of the factors of variation of tool wear is discussed in this paper. It is well known that nitrogen is included in the diamond lattices. Therefore, through the identification of nitrogen impurity by I.R. absorption spectrum, measurements of Hertzian strength, and measurements of tool life by machining experiments, the effect of the nitrogen impurity on the tool wear and tool life has been clarified.

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In this research work, turnig performances of a boron doped diamond bite, which possesses electrical conductivity and high oxidation temperature, were investigated. From the result of turning experiment for optical glass (BK7), it was found that the boron doped diamond bite showed considerably little flank wear at cutting tip.

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To understand the wear mechanism of diamond tool in machining of ferrous metals, an erosion test simulating wear process and ab-initio molecular orbital calculation are carried out. The results of the tests and analyses show that the essential wear mechanism at the temperature higher than 1000K is the dissociation of carbon atoms on diamond surface due to the interaction with iron surface. The wear rate is controlled by the removal rate of dissociated carbon atoms from the tool-work interface such as diffusion into workpiece. At the temperature lower than 900K, the mechanism involves the removal of carbon atoms due to oxidization of diamond accompanied with deoxidization of iron oxide.

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Carbon nanocoils (spiral carbon nanotubes) are expected as a highly functional material for electromagnetic components such as electromagnetic wave absorbers and field emission devices and for mechanical components, such as nanosprings. However, electromagnetic or mechanical properties of carbon nanocoils have not been fully understood. In this paper, stable structures of carbon nanocoils and their mechanical properties are predicted based on molecular dynamics simulation with Tersoff inter-atomic potential.

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This study aims to clarity the effect of the vibration assisted cutting on the reduction of plastic deformation and the improvement of machined surface. This paper reports on the result of the cutting chip formation process obtained through the molecular dynamics simulations in the vibration cutting process of pure aluminum. From the simulation results, it is verified that the shear angle of cutting chip becomes larger with the increase of advancing speed in the advance cycle of cutting tool.

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Nanoimprint process is being proposed because pattern forming by present semiconductor lithography needs enormous costs. By using this process, nanostructure could be formed without expensive euipments and incidental process. Molecular dynamics simulation is carried out in this research in order to clarify conditions under which microstructures can be formed on the top surface of resin on a substrate by pressing a mold to the heated resin and then by cooling resin and pulling up the mold. It is shown that patterning capability depends largely on the size of the pattern and difference of the cohesive energy between mold and resin.

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Dip-pen nanolithography(DPN) is a method that do patterning directly on a substrate by using a scanning probe microscope (SPM) having a tip with molecular ink. Although physical properties of substrate and molecular ink are important, the mechanism of patterning has not been clarified yet. Then, to examine this mechanism, DPN is simulated by using Molecular Dynamics for various interaction between substrate and ink atoms. The influence of atomic interaction on pattarning performance is discussed with respect to ‘wetness’ of the ink.

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Although simulations of EDM(Electric Discharge Machining) have been carried out using various methods such as FEM, behavior of machining liquid is difficult to simulate in these methods because density of liquid changes widely. In this paper, simulation of EDM is carried out using SPH(Smoothed Particle Hydrodynamics) in which a wide change of liquid density can be handled. It is shown that at the time when 16 micro sec has elapsed from the beginning and when the discharge channel has diminished, heat is not yet transmitted enough from the heated liquid particles to the solid particles. However, a high pressure continues to act to the work surface even after the end of the sigle discharge pulse.

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The micro-machining technology of a nanometer scale is focused in various fields of engineering increasingly. In this paper, the nano-meter processing characteristic in the processing machine using the AFM mechanism is clarified by using FEM analysis. FEM analysis of nano-meter processing of the metal using the micro cantilever tool was performed. And comparison with the processing experiment by the AFM processing machine was performed. As a result, presumption of the processing depth in FEM analysis was attained. Moreover, we clarified influence which the contact angle of a tool has on processing.

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In the mature industrialized society, it has become difficult to perform profitable mass production — facilities with high productivity and flexibility are necessary. For machine tools which are core to such facilities, multi-tasking machines which can perform multiple processes by a single machine are the most suitable. The development trend of multi-tasking machines will be described.

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In this research, a polar coordinate desktop machine tool (P-DMT) was developed combining two rotary motions and one linear motion. The P-DMT is suitable for the machining and measurement of free form surface such as sculpture. However, it is difficult to assemble without alignment error and to control maintaining high accuracy. Therefore, a compensation method to eliminate alignment error was proposed here, based on the error transfer function in coordinate system. In addition, application of the P-DMT to actual wire cut machining and on-machine measurement were carried out. Through the experimental results, the availability of compensation was found.

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The need to reconfigure mass production machining lines, such as automotive part production lines, as changes are made to the part or as production level increases is recognized. However, the cost and labor involved in reconfiguring these lines is large, and so the desire for a machine capable of flexibility and ease in line re-configuration has developed. In response, a concept for an easily re-configurable production line composed of machines, including vertical and horizontal machining centers and a vertical turning machine, compactly developed to match the work size and built on a common base width and depth has been developed. For example, when part revision drives a line change from a horizontal to a vertical machining center, if the machines are of the same size and line interface, the line layout and work transport system would not require modification. Also, production level changes could be implemented by adding machines into the line. Because the line is composed of compact, equally-sized machines, overall floor space requirements are minimized. A production line composed of these machines is developed and discussed.

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