| Co-Investigator(Kenkyū-buntansha) |
LIN Bin Tianjin Univ., Mechanical Dept., Assistant Prof., 工学部, 助教授
TAN Jin Northeastern Univ., Mechanical Dept., Assistant Prof., 機械工学院, 講師
GUANG Qi Cai Northeastern Univ., Mechanical Dept., Prof., 機械工学院, 教授
喬 暁林 ハルビン工大, 咸海校・教授, 学長
IMAI Kenichiro Kanagawa Inst.Tech., Mechanical Dept., Research Asso., 工学部, 助手 (00308537)
QIAO-XIAO Lin Harbin Inst.Tech., Weihai Campus, The President
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| Research Abstract |
In our experimental results of shear(ductile) mode grinding, there are two serious problems as obstacles to its development. One is that the removal rate is limited by the contact area of wheel to workpiece which might cause heat generation. During the experiment, cracks caused by burning appeared on the ground surface ; shear mode grinding was impossible. From this result, we guessed that a large contact area limits the induction of coolant and promotes high temperatures in the coolant zone where heat is generated. In some types of grinding geometry a large contact area is difficult to avoid. Therefore, we already suggested that an alternative is to excite the wheel at ultrasonic frequency, which also admits coolant between wheel and workpiece, The results showed that the grinding force value was lower than that obtained with no vibration (conventional) grinding in shear mode. Further, exciting the wheel to induce a coolant in the contact zone, it was found possible that removal rate is increased 2 times.
Another is that the ground surface is scratched by various abrasive grits on the grinding wheel surface. Therefore, it is very difficult to keep a high quality ground surface, because, it is impossible to uniform the grits size, form, density, and orientation, using the grinding wheel. Thus, we were led to the conclusion that we need a new diamond tool instead of the grinding wheel. It is "Engineered Tool" . This tool has many small posts on the single crystal diamond surface (1,0,0). The diamond size is 2*2*1mm. Those posts was precisely machined 15 g in apart from each other, using Excimer Laser. Each post size is 5 mu m square, 10 mu m height. This represents a very high density of active diamond with constant and known spacing. We expect. that the "Engineered Tool" technique contrivutes to the development of high precision machining of hard and brittle materials, as contrasted with conventional machining.
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