Study On High Hardness Oxide Abrasive Polishing Technology

With the development of science and technology, Sapphire as an important component of the optoelectronic devices, infrared windows and fairing, it proposes more stringent requirements on the optical processing technology. Based on the solid abrasive grinding mechanism, this paper makes mechanics analysis of lapping grains in the process of lapping and determining the simplified model of the abrasive grains of the cutting edge in different removal form. By material removal stability experiments, verified the fixation the abrasive machining plane Sapphire craft is more stable. According to the material removal mechanism of traditional polishing, the flat Sapphire ring magnetorheological finishing material removal mechanism was discussed. The experimental research of plane Sapphire consolidation abrasive machining and ring magnetorheological finishing theoretical were studied in this thesis. The main contents of the study include the following aspects:1)The material removal experiment of the plane Sapphire was designed by ring magnetorheological polishing, the surface roughness Ra of plane Sapphire decreased from 136.7nm to 90.6nm after polishing and the material removal rate was 0.075μm/min. According to the Preston material removal equation, initially magnetorheological finishing material removal function theoretical model was established.2) Through grinding and polishing match experiments, a machining process was determined:the material rapid removed by choosing diamond pellets number W5; the surface damage reduction by choosing diamond pellets number W1.5; to improve the quality of the workpiece surface by choosing the magnetorheological finishing. An orthogonal experiment was carried out to analyze the effect of main parameters (magnetic flux density, the annular polishing head speed, the workpiece rotation speed and polishing gap) in ring magnetorheological finishing to the surface roughness and material removal efficiency, and prominent factors was analyzed meanwhile, we obtained the optimum parameters of the single indicator combinations and the maximum MRR was 0.057μm/min、the minimum surface roughness Ra was 0.988nm.3) Through the gray relational theory, we optimized the process parameters and obtained optimal process parameters:magnetic flux density is 3400Gs, workpiece speed is 120r/min, ring polishing head speed is 200r/min and polishing gap is 1.2mm. The surface roughness value Ra was 1.143nm and the material removal rate was 0.051μm/min were obtained by using the optimized experimented parameters to polish for magnetorheological finishing experiment.