Ductile Regime Grinding Aspheric Surface of Hot-Pressed Zinc Sulfide

Abstract

Aspheric lens of Zinc sulfide is widely used in infrared, but it is always formed by polishing with low efficiency, ductile regime grinding aspheric surface of hot-pressed zinc sulfide is studied to reduce time-consuming of polishing. The results of orthogonal grinding experiments demonstrate that the depth of grinding is the main influencing factor on ductile regime removal mechanisms and surface roughness Ra values which decrease with decreasing depth of grinding, and the optimal value is 7.6nm, the steady ductile regime removal mechanisms appears when depth of grinding is below 0.4μm. With diamond wheel by grain size of D20/30, machining parameters on the basis of orthogonal grinding experiments, the aspheric surface cross grinding experiments show that ductile regime removal is obtained only in little center areas of aspheric surface, most of aspheric surface is in brittle regime. Then, the ductile regime aspheric surface with roughness of 20.1nm is observed by cross grinding of diamond wheel with grain size of D4/8.