Computer aided ultra-precision micro-machining of metallic materials

Micro-machining technology is in general well known in the field of lithography, where most of the materials used have been brittle ones such as silicon-oxide. However, the requirement of producing micro-machine and/or micro-mechanism with metallic materials is increasing since a variety of workpiece configurations can be easily made. Thus, this study deals with the micro-machining of metallic workpieces with sculptured surface by use of a newly developed ultra-precision milling machine. This lathe-type ultra-precision milling machine, consisting of an z-motion table, a positionable spindle as c-rotational axis and x-motion table, is equipped with a pseudo-ball-endmill composed of a single crystal diamond tool mounted at the top of a high speed air spindle on the x-table. A control program has been developed to carry out 3-axis control micromachining. The 3-axis control program enables the tool to produce a human face-like surface with the surface roughness of 77 nm (Rmax) within a circular area of 3 mm in diameter. As a result, the possibility of generating ultraprecision sculptured metal workpieces is experimentally confirmed