Effect of cutting parameters on surface quality during diamond turning of micro-prism array

In order to achieve the high-quality roller mold used in roll-to-roll fabrication of optical prism films, this article investigates the effects of cutting parameters on surface quality during diamond turning of micro-prism array, and some cutting experiments are carried out on home-made ultra-precision drum roll lathe. The surface defects such as micro pits and burrs are presented and discussed at different cutting parameters. The experimental results show that, when the cutting depth is more than 4 µm, the plowing force becomes the dominant factor to remove material, which may cause the generation of micro pits on the side surface of micro prism. During multiple-step diamond turning of micro-prism array, the final cutting depth is recommended not to exceed 2 µm; in this case, there is no generation of micro pits and the height of burr is less than 13.6 nm. Moreover, the well-controlled cooling and chip evacuation can effectively improve the influence of cutting speed on surface quality. Finally, micro-prism array with pitch of 40 µm is successfully machined without apparent surface defects.