Ultra-precision Polishing of Outer Surface of Tube Using Magnetic Compound Fluid Wheel

Abstract:

A novel method employing magnetic compound fluid (MCF) wheel was proposed for polishing the outer surface of stainless steel tube. Firstly, a polishing apparatus was constructed. In addition, the distribution of the magnetic field of MCF wheel on the workpiece surface was explored by Maxwell software and Tesla meter, and the relationship between magnetic field distribution and material removal (MR) on the workpiece surface was investigated. Then, MR model was established and proved by the experiment results under specific experiment conditions. Finally, the influence laws of carbonyl iron powder particle size d_CIP, abrasive particle size d_AP, magnet speed n_m, workpiece speed n_c, and MCF supply amount V on surface roughness R_a and reduction rate were investigated through experiments, and the mechanisms of different parameters on surface quality were explored. Results show that the magnetic induction intensity during polishing is positively correlated with the polished profile of the workpiece. The trend of MR simulation is consistent with that of the experiment value, which proves the accuracy of MR model. When the revolution speeds of magnet and workpiece are 200 and 5000 r/min, respectively, and 2 mL MCF slurry containing 50wt% carbonyl iron powder (15 μm), 12wt% abrasive particle (7 μm), 3wt% α-cellulose, and 35wt% magnetic fluid was used, the final surface roughness decreases from 0.411 μm to 0.007 μm. After polishing for 100 min, the reduction rate is 98.297%, demonstrating that this method is appropriate for polishing the outer surface of tube.