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The crafts such as lacquerware have made unique strides through decorating techniques using gold such as “Makie”, the technique to draw picture by scattering powdered gold, and “Chinkin”, the technique to rub gold into the design engraved by carving knives. In conventional techniques, practical knowledge and ability are essential to produce craft products. Therefore, screen printing which consists of simple processes has been developed. However, screen printing requires a masking plate made of silk or nylon to create patterns for transcribing ink into objects. This paper presents the formation of a decorative film by inkjet printing with gold nanoparticles for crafts such as lacquerware. The proposed method consists of on-demand process, which makes design changeable without masking. The aims are threefold: 1) to establish a sintering process of gold nanoparticles for acrylonitrile butadiene styrene (ABS) and phenol resin substrates used for synthetic resin products; 2) to characterize the sintered gold film; 3) to examine applicability to industry. The major results obtained are as follows: the appearance and the reflectance spectra of the gold nanoparticle film vary with heat conditions; the proper heat conditions which prevent thermal damage to substrates are the temperature of 373 K or below for the ABS resin substrate, and 423 K or below for the phenol resin substrate, respectively; the gold nanoparticle film possessed a good surface integrity without any voids when the sintering temperature is higher than 323 K for 1 h. Moreover, the film had such a high adhesion to substrates that no separation occurred after cross-cut test; the proposed method applied a lacquerware product made of ABS resin, yielding the decorative film

Cutting fluid is commonly used during metal cutting process for cooling and lubrication. Fluid types are generally classified into mineral or fatty oils and water miscible oils. In Japan, the former is called water-insoluble coolants, and the latter is called water-soluble coolants. Water-insoluble coolants are specified as dangerous material by the Japanese law due to its flammability. Therefore, the water-insoluble coolants are not appropriate for unmanned operation of machine tools. Therefore, the usage rate of water-soluble coolants is increasing. Water soluble coolants are diluted with a water by several ten times. The waste management of the water-soluble coolant become important for environment-conscious green manufacturing. We have been developing a recycling system for water-soluble coolants. In the recycle system, water is extracted from the waste coolant and the water is then reutilized as a diluent of a new coolant. We have developed various types of chemical or bio-chemical water recovery methods for recycling systems. We found a commercially available amine-free water-soluble coolant is suitable for the recycling system. The processing time, processing cost, and the biochemical and chemical oxygen demand of the extracted water are improved by the amine-free water soluble coolant compared with a conventional amine-containing coolant. However, its corrosion inhibition performance was poor in general machining applications. Our cooperative company developed a prototype of a corrosion-inhibition-improved amine-free water-soluble cutting coolant. The prototype coolant showed a good stability and cooling and lubricating performances, and its recyclability was as good as that of conventional amine-free coolants. In this study, we focused on repeated recycling of the prototype coolant. We repeatedly applied the water recycling process to the recycled coolant. The recyclability of the prototype coolant was not affected by repeated recycling; however, process residues increased with the number of recycles, and a deterioration was noticed in the corrosion-inhibition performance of the coolant diluted with recycled water.

A wire tool having electrodeposited diamond grains is frequently used for machining hard and brittle materials such as silicon ingots, magnetic materials, ceramics, and sapphires. This study aims to examine the wear characteristics of the tool during the microgrooving of ceramics. We conducted microgrooving experiments for alumina ceramics. The results indicate that the grooving time and the machining distance influence the groove depth. However, as the damage in a wire tool progresses, the groove depth does not depend on the machining distance. A fast relative velocity leads to serious damage in the wire tool even when the machining time is short. In the case of wet grooving, the damage to the wire tool was smaller than that in the case of dry grooving.

The essential features and scale of sensor data was discussed to monitor the tool anomaly in the machining process from the pattern variation of large scale sensor data such as vibration and effective power. The cycle data, the time series sensor data collected with an acceleration or power sensor in one periodical machining of the given groove shape, had been measured periodically. In this study, the graphic pattern formed by overwriting the time series cycle data on a specific coordinate system was treated as the “big sensor data”. The big data from the effective power sensor can stably respond to the cutting power changes and showed a strong possibility as a detecting device for tool anomaly such as abrasive wear and chipping. While the big data from the acceleration sensor only responded to a big event like the chattering vibration. The number of cycle data needed to generate the big sensor data also affected on the detection sensitivity for tool anomaly. It had been required a family of time series sensor data enough to represent the cutting power change as a visual graphic pattern.

It is well-known that a series of cracks sometimes gets initiated perpendicular to the cutting edges on the rake faces of brittle cutting tools made of materials such as cemented carbide, ceramics, and cermet under high-speed intermittent cutting. The tools used in intermittent cutting processes are exposed to elevated temperatures during cutting and then cool quickly during the noncutting time. Previous studies have suggested that such repeated thermal shocks generate thermal stress in the tool and that the thermal cracks are then propagated by thermal fatigue. Recently, high-speed machining techniques have attracted the attention of researchers. To apply new cutting tool materials to this machining process, it is important to evaluate their thermal shock fatigue resistances. During high-speed intermittent cutting, the frequency of thermal shocks becomes high and the action area of the thermal shocks is limited to the rake face of the tool. Therefore, conventional thermal shock resistance evaluation methods are unsuitable for this case. Consequently, the authors have developed a new experimental evaluation method using a CO2 laser beam. In this study, we irradiated cemented carbide and TiN cermet cutting tools with the CO2 pulse laser beam and gauged the effectiveness of the proposed thermal shock fatigue resistance evaluation method. The results show a correlation between the thermal shock due to the CO2 pulse laser beam and those due to the intermittent cutting experiments.

An electroplated diamond wire tool is frequently used for the machining of hard and brittle materials such as silicon ingots, magnetic materials, ceramics, and sapphires. This study aims to examine the influence of brittle behavior of work materials on machinability (including tool wear); therefore, we conduct dynamic ultramicro hardness measurements and microgrooving experiments for three types of ceramics. The results indicate that the groove depth of a work material tends to increase with the processing time. Moreover, material properties of a work material, such as hardness and toughness, have a significant impact on the fluctuations in its groove depth. However, kerf width of a work material does not depend on the processing conditions and material properties. In addition, a faster relative velocity improves processing efficiency but also increases tool wear.

A damage-free cutting method called the constant- load feeding method is proposed as a high-precision machining method in carbon-fiber-reinforced plastic (CFRP) cutting. The constant-load feeding method can minimize cutting defects such as burrs and scuffing during diamond-saw cutting. In addition, there was no apparent cutting damage to the cutting surface from drilling with a high-speed steel twist drill. The cutting resistance was kept at a constant value during the entire process. The constant-load feeding can self-regulate the optimal tool feed rate to realize damage-free machining of CFRP composites without any feedback control systems based on the cutting-force.

Multi-wire saws with a diamond electrodeposited wire tool are widely used to slice hard and brittle materials. The properties of the materials significantly affect the saw’s performance in terms of slicing quality, efficiency, and accuracy. In this study, the effects of the material properties of workpieces on wire tool performance and tool wear are described. The main conclusions are as follows: the higher the hardness and toughness of the workpiece material, the longer the slicing time and greater the damage to the wire tool. The brittleness of the workpiece adversely affects the thickness variation more than its hardness. In addition, the frequency of chipping mainly depends on the hardness of the workpiece, whereas the chipping size mainly depends on the toughness of the workpiece.

A fret-saw blade is commonly used in micromachining or curve machining of various woods. However, there is a curvature limit for machining of free-form surfaces because a fret-saw blade has a thickness of several hundred microns and a width of several millimeters. Additionally, cutting with a fret-saw blade produces much wood meal as chips. If a fine wire cutting tool is used, more flexible machining, such as machining of high curvature free-form surfaces, is possible and the quantity of chip production drastically decreases. The main purpose of this study is to clarify the fundamental machinability of anisotropic materials cut with a fine wire tool. In this report, we describe the machinability of various woods that are naturally anisotropic materials using a fine wire cutting tool that has electrodeposited diamond grains on its surface. In addition, this report discusses the performance of a trial manufactured hand tool employing the same wire cutting tool. The main conclusions obtained in this study are as follows. Acceptable machining of anisotropic woods is possible using a fine wire cutting tool, and the kerf width produced with this wire tool is narrower than that produced with a fret-saw blade. Additionally, the wood species and the cutting direction with respect to the wood grain have a significant influence on the machinability of various woods. Moreover, a relatively smooth cross section is provided when wood is cut by the hand tool using the fine wire tool.

We examined the relation between the cutting force and the cutting characteristics of CFRP in diamond saw cutting. When a larger cutting force was applied, the cutting had been propagated with a mixed mechanism of the cutting by cutting edges and the cleaving of carbon fiber by shear force. While a good cutting surface was formed in the case of cutting with less than 23 N of cutting force. In this condition, the cutting had been propagated only by the cutting with cutting edges.

It is well known that a series of cracks running perpendicular to the cutting edge are sometimes formed on the rake face of brittle cutting tools during intermittent cutting. The cutting tool is exposed to elevated temperatures during the periods of cutting and is cooled quickly during noncutting times. It has been suggested that repeated thermal shocks to the tool during intermittent cutting generate thermal fatigue and result in the observed thermal cracks. Recently, a high speed machining technique has attracted attention. The tool temperature during the period of cutting corresponds to the cutting speed. In addition, the cooling and lubricating conditions affect the tool temperature during noncutting times. The thermal shock applied to the tool increases with increasing cutting speed and cooling conditions. Therefore, to achieve high-speed cutting, the evaluation of the thermal shock and thermal crack resistance of the cutting tool is important. In this study, as a basis for improving the thermal shock resistance of brittle cutting tools during high-speed intermittent cutting from the viewpoint of cutting conditions, we focused on the cooling conditions of the cutting operation. An experimental study was conducted to examine the effects of noncutting time on thermal crack initiation. Thermal crack initiation was found to be restrained by reducing the noncutting time. In the turning experiments, when the noncutting time was less than 10 ms, thermal crack initiation was remarkably decreased even for a cutting speed of 500 m/min. In the milling operation, the number of cutting cycles before thermal crack initiation decreased with increasing cutting speed under conditions where the cutting speed was less than 500 m/min. However, when the cutting speed was greater than 600 m/min, thermal crack initiation was restrained. We applied the minimal quantity lubrication (MQL) coolant supply to the intermittent cutting operation. The experimental results showed that the MQL diminished tool wear compared with that under the dry cutting condition and inhibited thermal crack initiation compared with that under the wet cutting condition.

We investigated the magnetic properties and domain structures of Nd–Fe–B sintered magnets with a Tb additive reacted and diffused from the sample surface. We characterized these magnets using vibrating sample magnetometry, Kerr effect microscopy, and electron probe microanalysis. In the reacted sample (R-Tb) in this study, the Tb concentration was higher on its surface (∼30 μm depth) and in its interior grain boundaries than inside the subsurface crystal grains. The saturation polarization (Js) was about 6% lower in the reacted sample than in the non-reacted sample (N-Tb); which should come from the Js decrease in the Tb-substituted regions in the R-Tb sample. The substitution greatly improved the coercivity (Hc) of the samples from 1.02 MA/m (N-Tb) to 1.72 MA/m (R-Tb). To understand the reason of this increase, we measured the domain widths (dD) from the near-surface region (5–10 μm depth) of the polished R-Tb sample and from deeper below the surface in the R-Tb and N-Tb samples. The average dD from the near-surface region of the polished R-Tb sample was approximately 20% wider than the other polished planes, where the dD was about 1.0 μm for both samples. In addition to considering the reasons for this coercivity enhancement, we used a novel step method to compare the demagnetization behaviors of the R-Tb and N-Tb samples. The R-Tb sample likely had enhanced coercivity mainly because of the difficulty of nucleating magnetic reversal portions. This difficulty was mainly caused by the enlargement of the anisotropy field (Ha = 2K1/Js) because of the decrease in saturation polarization by the Tb diffusion and reaction. The ∼20% wider average dD on the R-Tb surface polished plane was also explained mainly by this Js decrease.

Recently, the concern for the environment has been increasing rapidly. In machining processes, the treatment of water-soluble coolants waste has caused environmental problems. Water-soluble coolants contain surfactants, preservatives, and corrosion inhibitors for maintaining the stability and performance of the coolants. To reduce the management cost and environmental effect of water-soluble coolants, the authors have been studying a recycling system for water-soluble coolants. In the recycling system, oil-free recycle water is isolated from the coolant waste and reused as a diluent of the new coolant. The authors have been developing different types of water recovery methods for the recycling system, and the recovered water from the coolant waste has potential as a diluent for a new coolant. In this report, we focused on the amine (alkanolamine) -free water-soluble coolant. Some amine-free water-soluble coolants have been developed and are commercially available. A reduction in the environmental effect in the waste treatment of coolants is expected with amine-free coolants. We have demonstrated that the amine-free water-soluble coolant has equal or better cooling and lubricating performance compared with the conventional amine-containing coolant. In addition, the amine-free coolant shows good recyclability for the recycling system. The processing time of the recycling treatment of the amine-free coolant has been decreased by half with our recycling process compared with the conventional amine-containing coolant. In this report, we examined the stability, cooling performance and lubricating performance of the recycle amine-free water-soluble coolant in long term operation. The recycle amine-free water-soluble coolant is operated in a 3-axis machining center for several months. We observed concentration, pH, corrosion inhibition performance, cooling performance, and lubricating performance of the coolant. The results from these experiments show the amine-free water-soluble coolant has the advantage to use in the recycling system for water-soluble coolant.

Anisotropic materials are used in various fields because of their superior mechanical properties such as high specific strength. However, the surface generation mechanism in loose abrasive machining such as multi-wire sawing of anisotropic materials has many unknown characteristics. This study mainly aims to clarify the sliced surface generation mechanism in multi-wire sawing of glass fiber reinforced plastics (GFRP). Therefore, the slicing experiments and the wet lapping experiments are carried out in this study. In this paper, we describe the fundamental slicing characteristics of GFRP and the influence that the orientation angle of reinforcement fibers has on the newly generated surface of GFRP. We find that high-precision machining of GFRP is possible using a multi-wire saw. The slicing rate and thickness variation are not dependent on the orientation angle. However, sliced surface roughness depends on the orientation angle, and it tends to decrease when the orientation angle increases. In addition, sliced surface generation and polished surface generation involve similar mechanisms and produce very similar surface characteristics.

We propose a supervisory technique to monitor the material removal state and tool wear condition as well as the estimation method for overall power consumed in the machining from the effective spindle power change. The effective power (VAcosφ) was the optimal motor related parameter to represent the motor load. The cutting condition can be related with the effective power change by using the averaged effective power for 0.2 seconds. The mean effective power is in proportion to the material removal rate. In addition, the averaged effective power can monitor continuously the tool wear condition and tool breakage. There was a series of cutting conditions where the specific effective power becomes minimum in the grooving operation. Under the cutting conditions with the minimum specific effective power, the cutting would have been conducting at the least cutting resistance and less overall power consumed. These facts indicates that we can determine the cutting conditions, where the cutting resistance and overall power consumed are getting minimum at the same time, by measuring the effective spindle power change during the operation.

We propose a recycling system that can recover the useful water from the spent water soluble coolant by using a surfactant and powdered activated carbon. The processing of about 70 liters of actual spent water soluble coolant yielded about 60 liters of clear water with 6.7 of pH and 0.0 of Brix value. About 120 liters of recycle water-soluble coolant was prepared by diluting an emulsion type cutting fluid 20 times with the recycle water. The recycle coolant has been showing the very similar Brix value and pH changes as those of virgin coolant until 100 days usage. The recycle coolant also showed the same potential to inhibit the progress of flank wear as that of virgin coolant. These facts indicate that the recycled water can be utilized as a dilutor of renewal water-soluble coolant.

To reduce the management cost and environmental load of water-soluble coolant, authors have been studying on a metabolic system for water-soluble coolant. More than 90% of waste water-soluble coolant is composed of water phase. If the oily additives and contaminants can be isolated from the waste coolant, the amount of waste coolant decreases remarkably because the recycled water can be reutilized as a diluent of renewal coolant. Authors has been developed some types of water recovery methods for the metabolic system. To complete the metabolic system for water-soluble coolant, the coolant diluted with recovered water should have the same machining performance and long-term stability as those of coolant diluted with tap water. In this report, we examined the machining performance and ability change of water-soluble coolant diluted with recycled water under operations encountered in machine tool.

Tools coated with TiBON films of varying boron concentrations were made, and the influence of boron concentration on tool wear was investigated. The TiBON coating film acts as a lubricant at high temperature. Tools coated with such films were applied to the machining of difficult-to-cut materials (Ti-6Al-4V and Inconel 718), where the cutting temperature increases rapidly and heavy adhesion occurs. In the experiment, turning and interrupted cutting were performed. In cutting of Ti-6Al-4V, the tool coated with a film of high boron concentration showed long tool life. In turning of Inconel 718, the tool coated with a film of a boron concentration of 15% showed the longest tool life-about four times longer than that of a tool coated with TiAlN.

In order to achieve a high efficiency and accuracy in slicing of hard and brittle materials, a work rotating type multi-wire sawing method has been devised. Work rotating type multi-wire sawing is one of the most effective slicing methods for hard and brittle materials. However, this method has to fix a workpiece at the end of the slicing process. When a diameter of workpiece is large, this fixation becomes difficult. The main purpose of this study is to propose a newly developed bundled workpieces method. By this method, several workpieces are bundled up around a core material and fixation of workpiece becomes needless. This new method is expected to prevent the sliced wafers from scattering and to enable complete slicing. The work material used in this study is borosilicate glass. The main results obtained are as follows. (1) Work rotating type multi-wire sawing using the bundled workpieces method makes it possible to prevent the wafers from breaking off before the completion of slicing, and to prevent them from scattering. (2) Work rotating type multi-wire sawing using coated bundled workpieces makes it possible to stabilize the slicing performance. (3) Work rotating type multi-wire sawing using this method improves the slicing rate. (4) Slicing precision of the normal work rotating type multi-wire sawing and bundled workpieces method is the same grade.

This paper presents the results of a series of experiments performed to examine the validity of a theoretical model for evaluation of cutting forces and machining error in ball end milling of curved surfaces. The experiments are carried out at various cutting conditions, for both contouring and ramping of convex and concave surfaces. A high precision machining center is used in the cutting tests. In contouring, the machining error is measured with an electric micrometer, while in ramping it is measured on a 3-coordinate measuring machine. The results show that in contouring, the cutting force component that influences the machining error decreases with an increase in milling position angle, while in ramping, the two force components that influence the machining error are hardly affected by the milling position angle. Moreover, in contouring, high machining accuracy is achieved in “Up cross-feed, Up cut” and “Down cross-feed, Down cut” modes, while in ramping, high machining accuracy is achieved in “Left cross-feed, Downward cut” and “Right cross-feed, Upward cut” modes. The theoretical and experimental results show reasonably good agreement.

Slicing with work rotating type multi-wire saw will be considered in the near future as one of the effective methods for slicing hard and brittle materials such as silicon ingots. In order to decrease the supplied value of slurry in slicing hard and brittle materials, the work rotating type multi-wire sawing characteristics using high viscosity slurry are investigated experimentally. This type of slurry is inferior to the conventional slurry in removing chips from the slicing regions due to its poor permeability. The work rotating type multi-wire saw is applied to improve the supply on slicing regions. Unlike the slicing process by a conventional multi-wire saw, the wire maintains intermittent contact with the workpiece during the process, thereby making it easy for slicing debris to escape from the slicing regions. Borosilicate glass, which is cylindrical (φ 10), is used as work material. The main results obtained are as follows. The work rotating type multi-wire saw makes it possible to use the slurry of high viscosity in slicing of hard and brittle materials. Using high viscosity slurry in work rotating type multiwire saw makes it possible to decrease the supplied volume of slurry. The use of high viscosity slurry in work rotating type multi-wire saw improves the surface roughness of the sliced surface.

Fuzzy control is applied to the superfinishing in order to optimize the cutting ability of the stone. The finishing performance of vitrified bonded WA stone is regarded as the fuzzy goal. At the beginning of cutting, the stone is in the stage of cutting to get high stock removal rate. But the cutting ability is decreasing as the finishing proceeds and is lost at the end of finishing, resulting in getting the smooth surface. A cutting resistance is used to monitor the cutting condition of stone. The cutting ability of stone is controlled by both the stone pressure and the amount of electricity for electrolytic in-process dressing. A water-solution type coolant and metal bonded diamond stone are used. The main results obtained are as follows. Fuzzy control makes it possible to give the optimized cutting ability to the diamond stone. In the first case, it is possible to get the large stock removal following the smooth surface in a limited time. In second case, it is possible to minimize the finishing time in which the finishing performance intended in stock removal and surface roughness is obtained. In third case, it is possible to keep the cutting ability of stone constant for a long time.

The machining damage done to the surface of ceramics by superfinishing is investigated experimentally. The bending strength of the ceramics finished is measured. The influence of the grain size and the finishing conditions on the bending strength is investigated. The work materials used are alumina Al2O3 sintered under atmospheric pressure and Mn-Zn ferrite sintered under HIP. The results are as follows. Superfinishing is very effective in removing the machining damage and improving the bending strength of the ground ceramic. Using a finer grain under lower stone pressure makes it possible to remove the work material as chips by plastic deformation and decrease the machining damage on the surface. It is estimated that the bending strength is influenced by the median cracks which are formed under the bottom of the groove by active grains. It is possible to increase the bending strength, using the stone under the condition of glazing.

In order to simplify the treatment of coolant in production systems, the superfinishing characteristics under the condition of water-solution type coolant are investigated experimentally. This type of coolant is inferior to an oil type coolant in removing chips from the stone because of its poor permeability. Electrolytic in-process dressing is applied to promote the self-dressing of diamond stone. As work materials, alumina which is sintered under atmospheric pressure and soft steel (equivalent to 0.15% carbon steel) are used. The results obtained are as follows. Electrolytic in-process dressing makes it possible to use the coolant of water-solution in superfinishing. The suitable conditions in electrolytic in-process dressing depend on the machinability of work materials. The soft steel whose chips are easy to make a loading on the working surface of stone needs the stronger dressing. A concentration of some percent is sufficient for a coolant to maintain its essential properties. The electrolytic in-process dressing is more effective for harder or finer stone, because it can control the cutting ability of the stone.

A new method of the superfinishing is investigated, in which the cutting ability of diamond stone is controlled by changing the strength of electrolytic in-process dressing. Water-solution type coolant and metal bonded stone are used to employ the electrolytic dressing. As work materials, a carbon steel S 45 C, a bearing steel SUJ 2 and alumina are used. The results obtained are as follows. It is effective for control of electrolytic dressing to change the operating time of electrolysis or the ratio of on-time to off-time in electric pulse. As the dressing becomes stronger, the cutting ability of stone improves and the metal removal rate becomes larger. As the dressing becomes weaker, the cutting ability of stone is lost and then the surface roughness of workpiece becomes smaller. The cutting ability of stone which has been lost in finishing operation can be regenerated again applying the strong electrolysis. This in-process dressing method makes it possible to obtain the intended finishing performances of metal removal rate and surface roughness, and to finish several work materials of different machinability using a same kind of stone.

This paper presents an analysis of chatter vibration in ball end milling of curved surfaces using time domain approach. A model for dynamic cutting process, which takes into consideration the variation of helix angle of the ball end mill along the cutting edge, is developed. The vibration of the tool is calculated by using a lumped-parameter model with two degrees of freedom. The chatter stability limit is indicated by the critical nominal depth of cut. The results show that chatter stability is very low for low spindle speeds. Also, the stability is lower for low and high milling position angles, and higher for intermediate milling position angles.