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Research on machining mechanics and experiment of ultrasonic-magnetorheological compound finishing

In this paper, Ultrasonic-Magnetorheological Compound finishing (UMC finishing), which is a new kind of polishing method, is first presented for the ultraprecision machining of concave optical surface with small radius. The principle of UMC finishing is studied and experimental set-up is developed based on the foregoing study. Experiments are carried out to verify the mechanics of UMC finishing. The results show that the surface roughness of the polished optical glass by UMC finishing is on nano-scale, which can satisfy the optical surface quality requirement. Furthermore, UMC finishing can also have higher machining efficiency than magnetorheological finishing under the same experiment conditions.