Machinability of Copper in Ultra-Precision Micro Diamond Cutting

The results of experimental study on micro-machining of copper with single crystal diamond tools are presented. Two kinds of diamond cutting of copper were carried out on an ultra precision fly cutting machine, one of which is conventional three dimensional fly cutting employing a diamond tool with circular edge, and the other quasi-orthogonal cutting. The orthogonal cutting tests were carried out under various nominal deptho of out from 3.0 μm down to 0.0025 μm (2.5 nm). The machinability in micro-machining was discussed from the viewpoints of the chip formation, the cutting forces and the surface integrity of the workpiece. It is confirmed that the continuous chips are formed at a nominal depth of cut of 2.5 nm and the nominal specific cutting resistances increase drastically with a decrease in the depth of cut.