チップブレーカの切りくず折断性能(第1報)

Abstract

For the breaking of chip in metal cutting, chip-breakers equipped on cutting tool are not almighty but effective only in limited range of cutting conditions. In the continuous cutting operation of ductile metals, such as the turning of steel, especially when the operation is automated, the selection of appropriate chip-breaker and of the conditions for chip breaking are extremely important. There have been, however, very little information available on this subject. In this report, a series of cutting test on 0.45% C steel using the carbide tool with parallel groove chip-breaker reveals the following conclusions : (1) In most cases, the range of chip breaking can be indicated both by the lower boundaries of the feed and the depth of cut. (2) The absence of and the reverse direction of the side curl of chip are unfavorable for the chip breaking. (3) The lower boundary of feed is varied not only by the cutting speed, width of chip-breaker groove and approach angle, but also by the corner radius of cutting tool. (4) The lower boundary of the depth of cut is roughly equal to the corner radius of cutting tool, but is independent from other conditions.