Machining of micro-channels and pyramid patterns using elliptical vibration cutting

Precision machining of micro-channels and quadrangular pyramids was studied using elliptical vibration cutting (EVC). A single crystal diamond tool with the trapezoidal shape was specially developed, and the tool was attached to the orthogonally arranged dual piezoelectric actuators to make the tool traverse an elliptical path at a frequency of 18 kHz for EVC. When the conventional micro-shaping method was applied to create microgrooves and patterns on workpieces of different materials, it was observed that (1) relatively large shear deformation induced periodic waves and partial tearing on the surface of brass which has relatively small brittleness, (2) a significant amount of burrs were formed on ductile copper, and (3) fractures of microstructures were observed on brittle nickel. In contrast, the application of EVC greatly reduced cutting resistance which, in turn, inhibited formation of burr and fracture of the microstructure and prevented degradation of surface quality from shear deformation, collectively contributing to significantly improving form accuracy of micro-channels and pyramid patterns.