Applying fuzzy grey relationship analysis and Taguchi method in polishing surfaces of magnetic materials by using magnetorheological fluid

With the development of mould manufacturing industry, the high precision polishing technologies of Ni–P-coated SKD11 steel are in high demand. In this work, the factors influencing the magnetic material polishing process were determined by investigating the force distribution of carbonyl iron (CIPs) and abrasive particles (APs) in the working surface of magnetorheological fluid (MRF). The influence of certain factors, such as the diameters of the CIPs and the APs and the current and working distance (K), on the polishing surface quality, was assessed by fuzzy grey and Taguchi analysis. Results showed that the values of the fuzzy grey relationships with the surface quality of the factors were 0.4914, 0.7797, 0.6686 and 0.7461. Result showed that the fuzzy grey relationship point of factors known as diameters of the AGs had the most remarkable influence on the polishing effect, and the effect of CIP diameter was insignificant. The MRF contained commercially available CIPs that had been successfully applied for polishing the surface of magnetic materials with extremely high accuracy (surface roughness Ra = 0.561 nm) without leaving scratches on the surface after polishing.