Geometric deviations in the production of micro-milling tools and their influence on the cutting process

For micro-milling tools with decreasing diameter D < 0.5 mm the requirements for the manufacturing rise up and the risk of geometrical deviations of the cutting edges increase. In this investigation industrial produced micro-milling tools with a diameter of D = 0.2 mm made of cemented carbide were analysed. Micro-milling tools with variable macro geometry were selected and used for the machining of mould steel. The influence of the geometrical deviations on the wear behaviour and the surface roughness of the machined steel were examined. It is shown that the variable tool geometry lead to wear of the minor cutting edges S'. Furthermore, an influence on the surface roughness of the machined workpiece is determined.