In order to improve the shear thinning property of magnetorheological solution and enhance the polishing efficiency of magnetorheological polishing, this paper combined shear thickening solution with magnetorheological solution to make magnetorheological shear thickening solution, and investigated the polishing performance and mechanical properties of the polishing solution.In order to improve the intensity of magnetorheological effect and shear thickening effect, single-factor experiments were designed to investigate the effect of magnetorheological effect on shear thickening effect by carbonyl iron powder mass fraction and magnetic field strength, and to investigate the effect of viscosity on magnetorheological polishing by controlling silica mass fraction, mixed solution ratio, spindle speed and abrasive mass fraction. It was found that a better polished surface could be obtained with a weaker magnetic field and a lower mass fraction of carbonyl iron powder, so that the wafer surface roughness could be reduced to Ra 20 nm, the material removal rate reached 1764 nm/min, and the tangential force variation amplitude reached 1.731 N.The tangential force and rotational speed were converted into viscosity versus shear rate by the equation, and it was found that the viscosity increased with increasing shear rate.Meanwhile, with the increase of silica mass fraction, mixed solution ratio and abrasive concentration, the viscosity of polishing solution increased and the size of polishing area decreased. The study of rotational speed shows that the magneto-rheological solution prepared in this study has shear thickening performance, and the corresponding magnetic field parameters and viscosity parameters can be controlled to effectively enhance the polishing efficiency, improve the polishing quality and enhance the performance of magneto-rheological solution polishing solution.
 

Magnetorheological polishing fluid,Shear thickening,Ultra-precision machining,Shear force