Due to the small uncut chip thickness in micro – end-milling, which is comparable to the tool edge radius, and the low rigidity of the tool, the cutting process must frequently transit between rubbing/ploughing and cutting. This may reduce the machining stability and surface finish, and increase tool wear. In this study, these unique cutting phenomena were investigated by modeling, computer simulations, and experiments. As a result, a possibility of the unique cutting phenomena proposed has been certified.

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As machining fluid contains oil, extreme pressure agents, surface active agents, etc., effluent treatment of waste fluid is necessary, such as incineration or coagulative precipitation. Therefore, it is necessary to reduce the amounts of machining fluid used to lessen environmental load and minimize disposal costs. In this investigation, an electric rust preventive machining method that uses only water as machining fluid was developed. A water recycling system was developed and verified. This system consists of 2 parts. First, an electric rust preventive chip sedimentation system, which separates chips, achieves 72 h rust prevention of chips in water. Second, a water reproducing system, which uses a reverse osmosis membrane, removes minute chips and ions and purifies the used water.

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Optical fiber end-plane machining is characterized by atomic force microscopy (AFM) scratching. We use silica (SiO₂), ceria (CeO₂), alumina (Al₂O₃), and zirconia (ZrO₂), as well as diamond, as the AFM tip material. These oxides are commonly considered to have chemical effects as abrasive materials. Here, the influence of ambient-liquid pH change is also examined. For evaluation of machining, the AFM tip scratches a rectangular area of the fiber end plane including the fiber core in liquid ambient. Consequently, with increasing pH, silica and diamond tips machined greater volumes than conventional methods. For silica, the tip abrasion and amount machined were the same. The other material tips exhibited peculiar scratch characteristics with pH change.

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The cutting properties of cobalt-free tungsten carbide using a monocrystalline diamond tool were investigated experimentally. Cutting-point temperature was measured using a dual-color radiation pyrometer and an optical fiber under different atmospheres, such as air, nitrogen gas, and argon gas. The cutting-point temperature was highest in argon gas, followed by nitrogen gas and air. The volume of diamond wear was also highest in argon gas, followed by nitrogen gas and air. This order agrees with that of the friction coefficient. As the maximum temperature of cutting-point was less than 250°C, the physical and chemical properties of the diamond and the tungsten carbide did not change during the cutting process. Diamond wear is caused by mechanical abrasion, rather than any chemical reaction, which will be accelerated under high temperature. Although abrasive wear of the diamond tool was reduced in air due to an adhering layer of oxygen, which acts as a lubricant, oxygen promoted the occurrence of diamond-tool chipping.

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Despite the large number of methods available for deburring the outside of parts, it is difficult to remove burrs from the inside of small and long parts. Here, a new magnetic internal deburring method is proposed. This method involves application of a magnetic field-assisted machining process using a magnetic tool. It is a new internal magnetic deburring method for removing only burrs in the internal surfaces of tubes. We experimentally examined the deburring of a drilled hole on the inside of SUS304 stainless steel tubing. This deburring experiment was performed for drill holes 1 mm in diameter. The results showed that such internal burrs could be removed using this magnetic deburring process. The height of the burr was successfully reduced from 104 m to 2.5 m, confirming the effectiveness of this new internal deburring method.

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