SPDT and standard CNC-grinding of tungsten carbide molds for precision glass molding: an experimental process analysis

Abstract

The contents of this work are based on [1], [2] and [3]. Using the three wagons approach, critical parameters were identified and the process window of ductile machining was considerably enlarged. This made it possible to increase the critical depth of cut, which is ten times greater than predicted by the Bifano formula. A new formula to describe the machining process was developed and verified experimentally. In addition, the level of surface roughness (Sq) generated in ductile mode was analyzed and a formula was generated that allows roughness prediction depending on the critical process parameters. Finally, both formulas were used to create optimized sets of process parameters that produce a "first light" in ductile machining for a) single point diamond turning (SPDT) on ultra-precision machines (UPM) of binder-free carbide form and b) non-UPM, standard CNC ductile grinding of WC and glass.