Abstract
The saw-toothed chip on machining metals is thought to have a significant influence on the tool wear or the quality of finished surface. The mechanism of saw-toothed chip formation process is entirely complicate and still not understood. The present study was carried out to find the morphology and the forming ranges of the saw-toothed chip on machining metals. The SUS 304 steel, titanium, 18% Ni-maraging steel, and Ti 6 Al 4 V alloy were employed for workpiece, while the M20 sintered carbide was used for cutting tool. The results obtained are as follows :
(1) The saw-toothed chip is formed at the speeds above 50 to 100m/min on machining the SUS 304 steel, above 10 to 50 m/min for machining the maraging steel, and between0.1to 500m/min for both the titanium and the Ti6A14V.
(2) The pitch of shear zones, as well as the distance of slips, are of the same order as the depth of cut, and these increase in the order of the maraging steel, Ti 6 Al 4 V, titanium, and SUS 304 steel.
(3) The rake angle has a little effect on the relation of cutting speed vs. pitch of shear zones, but a great effect on the relation of cutting speed vs. distance of slips.
(4) The pitch of shear zones increases proportionally with the depth of cut, but it increases with cutting speed when machining the titanium and decreases when machining the SUS 304 steel.
