Model for formation of surface of amorphous polymers machined with diamond tool

The orthogonal chip formation processes in cutting amorphous polymers (PMMA and VP-MA) with a diamond tool are investigated with dynamic microscopic observation technique. Based on that, the machined surface generation model for this cutting process is established. In addition, the machined surface topographies produced during these processes are surveyed and analyzed by using SMM (Scanning Mechanical Microscope). The radius of the micro-rounded cutting edge plays the most important part in the machined surface generation processes, especially for the VP-MA, which is more ductile than PMMA. The smaller the radius of the cutting edge, the smoother is the machined surface; and what is more, rake angle of more than 20° is good for producing smooth machined surface.