| 초록 |
Using a test tool with sharp cutting edge, tool angle 30° and clearance angle 0°, the effect of the undeformed chip thickness on the cutting performance in modeled veneer cutting of sugi was investigated. The experimental conditions of nominal chip thickness were 0.13, 0.26, 0.45, 0.72, and 0.89 mm. The purpose of this study was to obtain the minimum chip thickness which could form the chip. The veneer cutting process consisted of cutting (1) with chip thickness of 0 to nominal chip thickness, cutting (2) with constant nominal chip thickness, cutting (3) with nominal chip thickness to chip thickness 0 and burnishing (4) with chip thickness 0. The cutting force, machined surface profile, tool feed and rotational angle of the work pieces were measured in all cutting processes. Changes of cutting force, frictional angle on the face, frictional angle on the back and cutting error were analyzed. In cutting (1) and cutting (3), no chip was produced with the undeformed chip thickness when the frictional angle was larger than 90°. The undeformed chip thickness at the frictional angle of 90° was the minimum chip thickness. In this experimental condition, the minimum chip thickness was about 0.2 mm regardless of nominal chip thickness. The burnishing force caused by the cutting tool pushed the remaining volume that could not be cut with chip thickness less than the minimum chip thickness. |
