Papers by Author: Manabu Iwai

Paper TitlePage

Authors: Kiyoshi Suzuki, Shoji Mishiro, Yoshiaki Shishido, Manabu Iwai, Wang Mei, Tetsutaro Uematsu
45
Authors: Kiyoshi Suzuki, Anurag Sharma, Sadao Sano, Manabu Iwai, Tetsutaro Uematsu
Abstract: Electrically conductive CVD diamond having a high thermal diffusivity, when used as an electrode for micro EDM, revealed very low wear compared to copper and Cu-W electrodes in the case of finish EDM condition, where the short pulse duration is adopted. In this research work polycrystalline diamond (PCD), which has a thermal conductivity similar to that of the electrically conductive CVD diamond, is introduced as a new composite electrode material for EDM. Various properties of PCD with respect to EDM of die-steel (SKD11) and tungsten carbide (G5) have been studied and compared with those of the electrically conductive CVD diamond, copper and copper-tungsten electrode materials. It is found that electrode wear and material removal rate decreased with an increase in thermal conductivity depending on the type of the PCD material when very short pulse duration of te=1µs is applied. Extremely low wear, 1/20~1/50 times of the Cu-W electrode in the case of EDM of tungsten carbide workpiece at short pulse duration and zero wear in the case of EDM at short and long pulse duration of SKD11 can be realized.
549
Authors: Kiyoshi Suzuki, Tetsutaro Uematsu, Manabu Iwai, Shinichi Ninomiya, Sadao Sano, Takeo Nakagawa
Abstract: A new complex grinding method named Ultrasonic Electrodischarging Grinding Method (US-ED-G in short) is described. In the US-ED-G, ultrasonic grinding and ED grinding are simultaneously carried out on an electrically conductive workpiece with a metal bond grinding wheel. When compared with other complex grinding methods, the US-ED-G is remarkably effective in reducing grinding force a great deal and maintaining grinding ability of a wheel for a long time in efficient grinding of extremely hard-to-grind ceramic materials like TiB2. A stock removal rate of 200mm3/min and a grinding ratio of 110 have been attained by selecting appropriate conditions in US-ED-G of TiB2. A compact and rigid ultrasonic attachment is also described, which was developed as a removable tool for carrying out US grinding and US-ED-grinding on a machining center or a grinding center.
439
Authors: Kiyoshi Suzuki, Shinichi Ninomiya, Manabu Iwai, Yoshiaki Shishido, Tetsutaro Uematsu
Abstract: To improve the characteristic of the floating nozzle method, a new coolant supply method using a coolant flow guided flexible sheet was developed. In this method, all the coolant supplied from the nozzle outlet can surely be directed immediately to the grinding point, because the coolant flow guided flexible sheet made of a thin sheet material is attracted to the wheel surface automatically, and confines the coolant between the wheel surface and the sheet. Therefore, the coolant can be completely prevented from deviating away from the grinding point. In fact, when the coolant flow rate of 4 l/min was supplied from the upper part of the wheel by using this method, the amount of coolant that reached the grinding point was 18 times higher than the case of only the floating nozzle method. It was clarified that this method had the effect to improve the grinding performance. Furthermore, this new method has a possibility of the wide application such as in profile grinding and cam grinding.
227
Authors: Kiyoshi Suzuki, Manabu Iwai, Shinichi Ninomiya, Keizo Takeuchi, Katsutoshi Tanaka, Y. Tanaka, Tetsutaro Uematsu
Abstract: Electrically conductive cutting edges diamond grinding wheels (EC-cutting edges D wheels) have properties such as, 1) convenient precise forming by EDM, 2) realization of high cutting edge density, 3) sufficiently large chip pockets along with fine cutting edges on large diamond grits, 4) contact sensing of the cutting edges with workpiece due to electrical conductivity, 5) expected application to the grinding of various types of steels due to high thermal resistance. Until now, the grinding ability of the sharp edges generated on the electrically conductive CVD diamond thick film wheel by electrodischarge trueing (ED trueing) was confirmed by grinding experiments using a small diameter lapping wheel and a small diameter disk wheel. In this research work, metal bonded diamond wheels containing boron doped electrically conductive diamond (EC diamond) grits, which possess high oxidation temperature, were trial manufactured. From the results of grinding test for an optical glass (BK7), it was found that the wear and grinding force for the EC diamond grits wheel were significantly low compared to a conventional diamond grits wheel. Furthermore, from the results of the investigation on ED trueing performance, a high trueing efficiency along with the possibility of cutting edge tip formation was confirmed.
57
Authors: Anurag Sharma, Shoji Mishiro, Kiyoshi Suzuki, Tomoyasu Imai, Tetsutaro Uematsu, Manabu Iwai
147
Authors: Manabu Iwai, Tetsutaro Uematsu, Li Lin, Anurag Sharma, Kiyoshi Suzuki
501
Authors: Kiyoshi Suzuki, Manabu Iwai, Anurag Sharma, Tetsutaro Uematsu, M. Kunieda, C.S. Liu
535
Authors: Shinichi Ninomiya, Manabu Iwai, Kazuyoshi Takano, Tokiteru Ueda, Kiyoshi Suzuki
Abstract: This paper deals with prediction of improvement in surface roughness in helical scan grinding by simulation of virtual ground surface with a 3D-CAD model. It has been found that, by choosing the value of parameters of several grit conditions such as grit arrangement, protrusion height, inclination angle and so on, randomly for a real wheel, the maximum unevenness of the virtual ground surface and tendency of its change with feed angle nearly coincide with the surface roughness in the experiment of helical scan grinding. It is found that this simulation method is effective for the prediction of a surface ground by helical scan grinding.
142
Authors: Shinichi Ninomiya, Fan Qiang, Toshiharu Shimizu, Manabu Iwai, Tetsutaro Uematsu, Kiyoshi Suzuki
Abstract: In order to apply the floating nozzle method to an angular grinding on the external cylindrical grinding, basic experiments on V-groove grinding with the wheel edge were performed on the surface-grinding machine. The results showed that the floating nozzle method could maintain a good control of the wheel edge wear, leading to improved surface roughness compared with a conventional nozzle.
326
Showing 1 to 10 of 45 Paper Titles