This paper presents the results from an experimental study about high speed turning of stainless steel with the primary focus on the influence of changing shape of tool inserts upon the tool life. In the experiments of the present study, stainless steel SUS304 was turned under jet coolant conditions with three different shapes of inserts at a cutting speed of 300 m/min. The tool life was not as much extended as was expected when the shape of tool flank was changed under pressure 0.3 MPa. The results indicate that the size of film boiling area is the chief factor on the tool life in this case, and changing shape of the flank face will not lead to an reduction in film boiling area.

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Inconel 718 is wildly used and catalogued as one of the different-to-cut materials in aerospace industry. Recently several papers reported that micro-texture fabricated on a tool insert is able to improve the mechanical and thermal conditions at the insert faces. The purpose of this paper is to investigate the effect of micro-texture at the insert flank face on the evolution of flank wear in turning of Inconel 718 under different coolant supply methods. Four patterns of micro-texture were fabricated on the flank face of the coated cemented carbide insert at three levels of texture depth. After the finish-cutting experiments and measurements, it was found that micro-texture consisting of 10 m-deep microgrooves vertical to the cutting edge enhanced the cutting performance and exhibited the longest tool life.

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In order to enhance cutting performance of a CVD diamond coating tool, short-pulse laser processing is applied to edge sharpening of a commercially-available CVD diamond coating tool. Cutting performance for the sharpened CVD diamond tools was estimated by face turning of cemented carbide (more than HRC 60). By sharpening with the short pulse laser, only uniform flank wear gradually progressed without chipping and crack propagation as is in the case of cutting metals with good ductility. Consequently, the proposed sharpening process with short pulse laser has a high potential to improve cutting performance of CVD diamond coating tools.

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High-speed cutting, if feasible, may improve the efficiency of machining. Since the higher the cutting speed, the larger the temperature rises, the high-speed cutting should considerably promote the thermochemical wear and then drastically reduce the life of tool. In this study, we focused on extremely short time cutting. In this method, tool temperature can be considerably suppressed by controlling the thermal diffusion time between a cutting tool and work piece, i.e., thermochemical wear can be suppressed by far less level. Through experiments, the effects of the cutting period during a single pass on the tool temperature and tool wear were investigated.

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In this study, the failure process of a diamond-coated ball end mill was investigated. For a cutting tool, a two-flute ball end mill coated by a multi diamond layer with a total thickness of 20μm was used. For work specimens, four types of WC-Co blanks with different WC particle diameters and Co contents were used. Through cutting experiments, changes in cutting forces were monitored. In addition, microscope images of flank and rake faces were also obtained every scheduled cutting volume. From experiments, it was found that the failure undergoes two steps of development. Furthermore, by comparison between the results in different work specimens, it was found that the larger WC particle diameter and the lower Co content, the higher wear rate of diamond coating on the flank face.

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Along with the expansion of a recent power demand, the production of the steam turbine blades has increased, and a lot of forged materials of 12Cr steel, the ferritic heat-resisting steels have become widely used for this usage. However, although this material seems an excellent one as the heat-resisting steels, it necessitates correcting the deformation after machining, and, thus, lowers productivity. Therefore, we started a basic experimental research, and through a series of tests, we could find that 12Cr steel is a sticky material, that the residual stresses after machining concentrate on the surface neighborhood, and that this influences the deformation of blades.

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This paper proposed a new cutting method employing ultra-low-frequency (ULF) vibration of less than several Hz generated by an NC program in order to achieve high performance dry machining of titanium alloys. The results of turning experiments at a cutting speed of 100 m/min showed that the developed method significantly reduces crater wear in machining of Ti-6Al-4V even under the machining conditions. Moreover, the mechanism that ULF vibration affects and the influence caused by actual cutting time and non-cutting time in each individual vibration period on the amount of crater wear were investigated.

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In driven rotary cutting, adhesions sometimes occur on the tool, causing increased wear. The influences of the coolant supplying method on adhesion and wear was investigated, because how easily adhesions can occur depends on the cutting temperature. Results showed that in a circumferential velocity ratio of 1.0, there is no adhesion on the tool after cutting. In a circumferential velocity ratio of 2.0, adhesion occurred with overcooling of the flood coolant, and wear increased by adhesions to the rotating tool.

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Stainless steel machined parts are widely used in semiconductor manufacturing, automobile and aerospace industry and so on. This study describes about the characteristics of SUS304 austenitic stainless steel machined surfaces by end milling and burnishing processing on the machining center. It is found by metallographic structure analysis by X-ray diffraction test for surface-hardened layers of steel that SUS304 which have originally austenitic structure before burnishing process is changed to martensitic structure. In this paper, relationship between burnishing conditions and metallographic structure was experimentally evaluated. As a result, relationship between hardness and martensitic structure of SUS304 is clearly observed by the ratio of austenitic and martensitic structures.

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When cutting freeform surface using NC machine tools, two problems occurred. The first arises because the actual feedrate deviates from the command feedrate. The second is the decreasing surface quality due to the large acceleration and deceleration of the control axes. The main cause is the fact that the toolpath of the NC program does not consider control characters .In this paper, an automatic identification method of a sampling time and a generation method of an NC program that considers sampling time are proposed. In addition, a system is proposed to estimate the machining time. The effectiveness of the proposed methods is confirmed by experiments.

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In the machining process of medical products made of polysulfone material, it is strongly required to reduce the surface roughness and burr. It is well known that tool mark is the primary cause of surface roughness on the slot shape generated by the machining process. The type of tool mark on the machined surface is usually determined by the trajectory and shape of the cutting edge of the end mill. Therefore, in this study, we proposed a new shape of cutting edge with a flat profile. The proposed shape is generated by grinding process, by modifying both concave angle and the amount of ground area. In this study, we investigated the relationships among cutting conditions, surface roughness, and tool mark with the ground end mill.

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This paper highlights the influence of tool wear on the energy balance in precision hard turning using CBN cutting tools. Experimental plan includes continuous measurements of the tool nose wear VB_C and the corresponding changes of component forces F_c , F_f and F_p . Variable factors were feed rate, depth of cut and tool nose radius. The experimental data were recorded during wear test duration of maximum 100 min. As a result, the specific cutting and ploughing energies were determined for all measuring points. It was reasoned that the balance between the specific and ploughing energies can effectively be used to optimize hard machining operations.

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Chatter prediction requires tool-tip FRF to be identified for every tool clamped on the machine. To avoid repetitive time-consuming tests, receptance coupling approaches are used to predict tool-tip FRFs: experimental dynamic behavior of the machine is coupled to a numerical model of the tool. To achieve required accuracy, such techniques require joint rotations to be identified. This procedure is usually carried out via calibration testing, increasing machine downtime. In this work a calibration-free novel receptance coupling technique is developed: tool and machine are connected in two points with only translational DOFs. Proposed technique was experimentally validated on different case-studies.

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The efficiency of high-speed milling process is often limited by the occurrence of chatter. Active control systems seem to represent a suitable solution for chatter suppression, because of their high adaptivity. Nevertheless, efforts still need to be made for the definition of the best control strategy. Accurate simulation tools are therefore necessary, in order to take into account the effects of the actuating system on the cutting process. In this paper an efficient full-discretization method for active chatter mitigation simulation in milling process is presented. The time domain model has been developed considering an active workpiece holder driven by piezo actuators. The proposed simulation tool has been experimentally validated on a milling test case.

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This study presents an analytical model to predict cutting force in hypoid gear cutting, in which the gear grooves are machined by sets of inner and outer cutting blades. Both of the blades finish the side and the end faces in the gear grooves. Different chip flows occurs on the end and the side edges on the blades. The chip flows are modeled by piling up orthogonal cuttings containing the cutting and the chip flow directions, where the chip flow direction is determined to minimize the cutting energy. The cutting forces loaded on the inner and the outer blades are predicted in the chip flow models. The presented model is validated in the cutting tests with measuring the cutting forces.

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This paper describes the analytical results of spindle displacement and excitation current in time and frequency domains, measured during the real-time simulation of regenerative chatter by using a magnetic excitation device. The measured vibration amplitudes were analyzed based on the stability lobes estimated from the spindle system compliance. The chatter frequencies were found to closely approximate the estimated values. In addition, chatter vibrations, the frequencies of which were not predicted, were observed at high cutting stiffness values. A shift in frequency was observed, wherein the chatter started at a higher frequency and shifted to a lower frequency.

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The test cutting process is indispensable especially for small radius ball end mill operation due to problems such as machining error and tool breakage. This test cutting, however, requires a lot of time and experiences. In order to solve the problem, a simulator that can predict the cutting force has been proposed. But, an equation of the uncut chip thickness is issues in the conventional model. This paper describes theoretical analysis of uncut chip thickness in small radius ball end mills. The feasibility of a new geometrically equation of uncut chip thickness is proposed in this paper.

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The objective of this research is to reproduce the cutting sound according to a machining status in virtual environment. This research is made to a feature analysis of cutting sounds in end milling. As a result, a tool runout is not influenced to a cutting sound's amplitude, and then the cutting sound is proportional to the cutting force value. There are also three special frequencies in the analyzed cutting sounds. One may be caused by a spindle speed, and others might be caused by a friction between a cutting tool and a workpiece. It is founded that these frequencies are very important to reproduce the cutting sounds due to the machining process through this analysis.

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Dynamic behaviours of a metalic material under high speed loading, such as in the case of high speed cutting, have a close relationship with the rate dependent microstructure evolution during plastic deformation. This fact is not taken into account in the conventional phenomenological modelling like Johnson-Cook (J-C) model. Gao-Zhang (G-Z) model, which is based on thermally activated dislocation motion theory, has thus been proposed to characterize the mechanical behaviours of material at high strain rates even beyond 10^4s^<-1>. This paper aims to compare the G-Z and J-C models over a wide range of strain rates. It was found that at a low strain rate (10^3s^<-1>-10^4s^<-1>), both the models give results close to the experimental; but that only the G-Z model makes correct predictions when the strain rate is greater than 10^4s^<-1>.

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This paper describes the effect of cutting edge angle on the machining accuracy of drilling holes on CFRP (Carbon Fiber Reinforced Plastic) plates. In order to improve the CFRP drilling technique, in this study, ball-nose end mill which has cutting edge angle 90 degree is used in several drilling tests with compressed air. Consequently, it is found that wear rate on bottom cutting edge depends on cutting distance and don't be affected by cutting conditions.

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The metal cutting process remains one of the most widely used methods in manufacturing. Computer simulations of metal cutting are a valuable tool to understand the physics involved and to predict the outcome of such processes. One of the most important results of such simulations is the prediction of process forces. However, there is a general trend of the normal forces being underreported, independent of the numerical method chosen. Supposed factors which affect the normal forces are the material compression underneath the rounded cutting tool edge and the springback accompanied by the compression. The focus of this work is thus to simulate the process forces and the springback employing mesh free methods. The results are verified using experimental data. Predicted process forces and springback show good agreement with the experimental data.

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This paper presents molecular dynamics simulation on nanoindentation of diamond indenter on a copper workpiece. Surface damages of the workpiece are caused in the contact detection process for ultra-precision fabrication and form measurement of surface by using a force sensor-integrated fast tool servo. Molecular dynamics simulations are carried out in this paper to theoretically investigate the geometries of the damages due to the contact deformation. Taking into consideration of the holding period at the maximum indentation depth between the loading and the unloading processes, the dependence of the indentation geometry on the holding time are observed. Based on the simulation results, physical properties of the workpiece are also analyzed.

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This paper investigates deformation mechanisms and surface quality of porous carbon in diamond turning process. Experiments were performed based on L_<16> Taguchi method for design of experiment (DOE), and the effects of three variables including feed rate, depth of cut and cutting speed were investigated. Three types of deformation occurred in the diamond turning process, which were influenced by feed rate and depth of cut. Feed rate had dominant effect on surface roughness followed by depth of cut. By controlling the feed rate and depth of cut, surface roughness of the machined surface were controllable. There was 25% decrease in the percentage of porosity after the machining process.

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In infrared spectroscopic analysis of the structures of protein crystals, a micro-flow cell made of single crystal calcium fluoride (CaF_2) is needed. In this research, fly cutting of micro grooves on a CaF_2 substrate was conducted using a single-crystal diamond tool. The effects of cutting direction, up/down cut, and tool rake angle on ductile-brittle transition of cutting behavior were investigated. Based on the experimental results and analysis, optimal cutting conditions were selected which enabled ductile machining of CaF_2 . As a result, a 10μm deep micro-flow cell was successfully fabricated with surface roughness of 2.4 nmRa. The availability of the flow cell was confirmed by visible absorption spectroscopy of protein.

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This study proposes a new polishing method using MCF (magnetic compound fluid) slurry for ultra-precision and high-efficiency polishing of fused silica. A semi-fixed abrasive tool called "MCF wheel" was proposed that is in practice produced by putting MCF slurry on the outer surface of ring-shaped permanent magnets. In this paper, method of a certain number of water supplying to MCF wheel in the polishing process is proposed. In the result, prolongation of wheel life is realized because of inhibition of polishing temperature by maintaining of optimal construction of MCF wheel. In addition, ultra precision smooth surface is manufactured.

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This paper presents an experimental investigation of ductile cutting of silicon by using a diamond tool with a negative rake angle. A diamond cutting tool with a zero rake angle is inclined to form a negative rake angle for a better performance in ductile cutting. A high-sensitivity force sensor is integrated with the tool holder for detection of the tool-sample contact and monitoring the thrust force in the cutting process. The unavoidable sample tilt was probed by using the force sensor integrated diamond tool as a stylus, so that microstructures can be directly fabricated along the tilted workpiece. With accurate tilt compensation, a microstructure array with a good uniformity was successfully fabricated on the silicon surface.

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In cylindrical grinding for a long workpiece, the elastic deformation of the workpiece reduces the shape accuracy because of its low stiffness. Therefore, it is very important to analyze the elastic deformation of the workpiece during grinding process. In this study, an advanced analyzing method of the shape error in case of a long workpiece was proposed. In the proposed method, the normal grinding force, which is the important factor for the elastic deformation of the workpiece, was estimated from the power consumption of the wheel motor. To evaluate the proposed analysis method, the analyzed shape error was compared with measured shape error obtained by grinding experiment.

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In machining of CFRP, the delamination occurs at interfaces between matrix resin and carbon fibers due to the machining heat causes a deterioration of the surface quality because of poor heat resistance of matrix resin. However, the thermal environments of CFRP at the machining point haven't been made clear enough. In this study, the grinding temperature is measured in grinding of CFRP under dry and wet with vitrified bond diamond wheel. Furthermore, variations of the instantaneous heat transfer coefficients at the grinding point are calculated based on the grinding temperature data, and the effect of grinding atmosphere on the heat transfer characteristics at the grinding point is investigated experimentally.

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Chemically strengthened glass plate is very hard. Machining is difficult for its hardness. In this study, the miniature drilling method was established to achieve high quality of the drilled hole, by drilling a chemically strengthened thin glass plate using an electroplated diamond tool with a diameter of 1mm or less. The developed tool with a diameter of 0.5 mm succeeded in a through-hole drilling of chemically strengthened glass plate. In the case of tool with a diameter of 0.5 mm, we succeeded in through-hole of chemically strengthened glass plate with a thickness of 1 mm. The maximum chipping size of the outlet hole by tool with a diameter of 0.5 mm was larger than that of the inlet hole.

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A high-quality machining method for polycrystalline diamond (PCD) with high efficiency is required. In this study, the authors developed a high-speed constant-pressure grinding method, and the grinding characteristics of PCD using a diamond grinding wheel were investigated. An improved removal rate and surface roughness were obtained by increasing the speed of grinding wheel and processing pressure. In addition, the effects of the coolant flow rate and the bonded materials of the grinding wheel on the grinding characteristics of PCD were examined.

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In this study, we aimed to develop high performance slurry for polishing glass. The characteristics of a soda-lime glass polishing were improved by the addition of a metallic salt into ZrO_2 slurry, which affected the workpiece surface. The removal rate of silica glass polishing was improved by the addition of zinc-oxide particles into ZrO_2 and CeO_2 slurries, which affected the abrasives. These results can be used to reduce CeO_2 consumption or develop substitute materials for CeO_2.

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A lot of highly precise surfaces are needed at the semiconductor and the medical field. For removing the machining traces of plane surfaces, magnetic abrasive finishing (MAF) is an effective method in which magnetic brush that formed by magnetic particles and magnetic force. In this reseach, to achieve super-precise surface, the influence exerted on finishing characteristics was considered, and the most suitable processing conditions were considered to figure out the finishing properties of MAF, three elements are set as objects in this study, including the size of abrasive particle, the types of magnetic pole and the clearance between workpiece and pole. In this study, the three elements have been studied and their best conditions have been found. At the same time, the magnetic flux densities of magnetic poles are investigated by electromagnetic simulation. At last, a new multistep finishing has been proposed that can finish plane surface into nanometer-scale. The surface roughness has been improved from 381.32 nm Ra into 12.02 nm Ra.

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Recently, to obtain a smooth surface of low roughness with high efficiency which is increasingly desired to be in precision machining. However, it is difficult for traditional machining technologies to achieve both high accuracy surface and high machining efficiency. This study is focused on application of an effective finishing method, which combines electrochemical machining (ECM) and magnetic abrasive finishing (MAF). Before this study, a novel complex machining tool that is capable of achieving two different processes has been designed. Then, a series of comparative experiments have been conducted in order to investigate the effect of electrochemical magnetic abrasive finishing (EMAF). The results show that EMAF process is able to obtain slightly higher quality surface and more material removal, which compares with the traditional MAF process. Furthermore, it is suggested that the combining method effectively reduces machining time.

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Manufacturing process of sapphire wafer is meeting huge challenge to fulfill the strict requirement of high surface quality and productivity in semiconductor industry. Chemical mechanical grinding (CMG) process can provide remarkably low surface roughness. However, the material removal rate (MRR) fails to meet expectation. Therefore, it is necessary to improve the MRR through the aid from chemical agent or proper environment. In this paper, both chemical agents and environmental factors which are inspired from the success of chemical mechanical polishing (CMP) of sapphire have been studied. From the experiment result, the material removal rate is proportional to pH value and peaks at pH=11 while surface active agent and oxidant contribute little to improve the MRR. High temperature of polishing slurry also helps to improve MRR in sapphire polishing, but will off-sets the effect of pH value. Secondly, the MRR increases with the increase of pressure and relative movement speed, and its increasing slope exceeds the prediction of Preston equation, especially at high pressure and/or high speed conditions.

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Magnesium alloys are promising materials for metallic biodegradable stent manufacturing. In order to achieve enhanced coatability and an effective rate of degradation, surface finishing is required for smoothing the surface and removing burrs produced by the heat ablation of the laser-cutting operation used to produce the meshed stent. This paper proposes a new finishing processing principle for magnesium alloy stents and describes an experimental setup designed to realize the principle. Finishing experiments were conducted using magnesium alloy tubes and stents to demonstrate the process feasibility and finishing characteristics.

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To achieve high surface flatness of large-diameter silicon wafers in double-sided polishing (DSP) process, kinematical model of DSP process was investigated. On the basis of the analytical model, optimization method of rotation conditions was developed for improving surface flatness across the whole wafer while preventing overload on DSP machine. Optimization for DSP process of 450 mm wafers was performed as case study and the results confirmed that the developed optimization method was effective in obtaining the appropriate rotation conditions for improving global flatness of wafers while suppressing the motor load on DSP machine.

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A nonwarped substrate is required for manufacturing processes of a semiconductor device or a liquid crystal display. However it is difficult to fabricate a nonwarped substrate, since a thin substrate cannot be chucked during the polishing process without deformation occurring. A freezing pin chuck has been developed to resolve this problem. This paper describes the chucking characteristics of a freezing pin chuck. As a result, it was demonstrated that this chuck could be used for polishing a quartz glass substrate.

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Shape Adaptive Grinding (SAG) is a new process for freeform finishing of difficult materials such as ceramics and high-performance alloys. The basic principle of SAG can be described as "semi-elasticity": compliance is achieved with freeform workpieces by an elastic spherical tool, while hard contact is simultaneously achieved by small rigid pellets covering this elastic tool (diamond or cubic boron nitride super-abrasives are embedded in these pellets). In this paper, we present recent developments in the application of SAG to (1) corrective grinding of aspheric silicon carbide optics, and (2) smoothing of high-performance titanium alloy components produced by additive manufacturing.

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In order to inspect the effect of a magnetic polishing method for an even surface (plane surface) and an uneven surface (concave and convex shape), we polish and compare with a plane surface, a concave shape and a convex shape. Results showed that a high rotation speed is good for plane polishing as well as whetstone grind, while for polishing the concave and convex shapes, a low rotation speed is more effective. We also found that, with the concave and convex shapes, the polishing effect worsened due to excess paste that inhibited rotation movement of the paste to the pile on the wall surface.

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In this study, the controllability of multi-wire EDM slicing with the group power supplying method was investigated in order to apply this method regardless of workpiece resistance. In the case of monocrystalline silicon of 0.01Ω・cm, although peak current of electrical discharge pulse ideally changed with number of processing wire electrodes, kerf width, surface roughness and diameter of crater were approximately constant at almost constant cutting speed regardless of number of processing wire electrode. On the other hand, polycrystalline silicon of 2-3Ω・cm, resulted in ideal control of discharge current by applying sufficient no-load voltage, but its increasing ratio of no-load voltage must be larger than that of low resistance workpiece.

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In our previous studies, a thin alumina film formation was possible by a large-area EB irradiation using a alumina target tube. However, film formation mechanism has not yet been clarified. In this study, the influences of magnetic property and electrical conductivity of a jig supporting an alumina target tube on the film formation were investigated. The spectrum of plasma generated on the substrate surface was measured during the EB irradiation. The results indicated that the film was formed by sputtering target material with the plasma of workpiece material caused by EB irradiation, and the magnetic property of the jig greatly influences on the film formation.

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In micro EDM, the machinability can be improved by vibrating the electrode, but the optimal vibration mode is not clear. In this study, in order to find the optimal vibration method for improving machinability, we developed a PZT-driven 3-axis vibration system to assist micro EDM. Compared to traditional Z-direction vibration, the 3-axis vibration had higher removability of debris especially when machining high-aspect holes, leading to an increase in material removal rate by a factor of 2. Among various 3-axis vibration modes, the spiral trajectory vibration mode was found to be the most effective, which significantly reduced the electrode wear and machined surface roughness.

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A curved-hole drilling method by EDM using a metal ball electrode suspended with a thin leading part from the head of an electrical discharge machine has been proposed. This report discussed the effects of the leading part structure and metal ball size on the machining characteristics. Experimental results showed that servo voltage was a dominant factor for stable machining. Furthermore, various types of curved-holes were attempted by varying the tilting angle and direction of workpiece during the process.

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Polycrystalline diamond (PCD) is widely used to fabricate cutting tools. In the electrical discharge machining (EDM) of PCD, thermal damage, such as graphitization of diamond grains, is a critical problem. In this study, we performed EDM of PCD using rotary cupronickel electrodes and investigated the structural changes of PCD by Raman spectroscopy. It was found that the PCD surfaces machined using the rotary cupronickel electrodes were smoother than those in conventional EDM. The results also showed that diamond graphitization decreased when electrical discharge energy decreased and/or when feed rate increased. In order to reduce graphitization of diamond, we proposed a dry EDM finishing method for PCD. Very low surface roughness and low thermal damage were successfully achieved.

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In micro electrical discharge machining, since the discharge energy determines the material removal per single pulse discharge, decrease of the discharge energy is important for miniaturization of minimum machinable size of micro EDM. In this study, in order to decrease the discharge energy by reducing the discharge current flowing from the stray capacitance, high electric resistance materials such as single-crystal silicon were used as an electrode. Experimental results of micro rods machining show that with the resistivity of the electrodes increased, the diameter of discharge craters generated on the machined micro rod was reduced. In addition, since the diameter of discharge craters could be reduced, a cemented tungsten carbide micro rod of 0.8 μm in diameter was obtained using the silicon tool electrode.

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This study deals with the investigation of the possibility to fabricate an arc-shaped hole on the inside wall of another straight hole by means of electrical discharge machining. Although the authors developed a device which can fabricate a hole inside another hole, the shape of the fabricated hole has been limited. Aiming to diversify the hole shape, the study improves the device so that it can fabricate such a hole with an arc-shaped axis. The experimental results indicate that such a hole can be fabricated. It is proven that the improved device has the ability to fabricate an arc-shaped hole inside another straight hole.

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This paper describes a method to increase the discharge energy in micro EDM with electrostatic induction feeding method (EIFM) by exploiting the resonance in circuit. Higher discharge energy per pulse can be achieved when machining is done at resonant frequency, f_r of the circuit due to minimum impedance. In this paper, explanation on machining at f_r using EIFM with controlled pulse train method is given. Method to perform non-contact electrical feeding using a feeding electrode is described. As a result, machining at f_r of the circuit gives higher discharge energy and better discharge continuity within the controlled pulse train duration.

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ECM is effective method for hard materials. However, such as titanium, passivity occurs and machining stops immediately. Electrochemical mechanical polishing (ECMP) is effective for materials that easily become passivated. In this paper, the machining characteristics of difficult-to-machine materials with Electrochemical Mechanical Polishing (ECMP) are investigated. From the result of ECMP with various applied voltages, optimum machining voltages to improve surface roughness exist for each material. We attempted to generate complex shape with Electrochemical Grinding (ECG) using small polisher. From the result, machining shape could be created by controlled scanning speed.

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Electrolyte jet machining is carried out by jetting the electrolyte from a nozzle toward the workpiece, while applying voltage between the nozzle and workpiece. This machining method can selectively process metallic materials regardless of its hardness. Therefore, difficult-to-cut materials, such as cemented carbide rod which is used as fine tool can be machined effectively if the proper electrolyte and power supply are used. Furthermore, in order to reduce the contacting area between the workpiece and electrolyte jet, side surface of the electrolyte jet was used to process the workpiece in this research. Also, the machining of complicated revolving surface was investigated by rotating the rod workpiece.

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The machining accuracy of electrochemical machining (ECM) is low since zones that far away from tool electrode are also machined. And the scattering of electrolyte solution during processing is also a severe environmental problem. To solve these problems, in this study, a novel method that not only limits the working area by sucking the electrolyte into the region between tool tip and the workpiece, but also prevents the electrolyte from scattering around was proposed. In this paper, the processing characteristics of some electrolyte solution with the proposed suction method, especially for the depth direction, were investigated. As a result, the machining accuracy by using a suction tool was greatly improved comparison with the dipping method.

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