Development of a Magnetorheological Finishing Machine for Small-Bore Part of Irregular Shape and Experimental Study

Magnetorheological finishing machine tool with small ball-end permanent-magnet polishing head is proposed as a method to solve the problem that small-bore parts of irregular shape with small curvature radius concave surface cannot be polished by traditional magnetorheological finishing machine tool. The four-axis linkage magnetorheological finishing machine tool with modular open numerical system and easy-operating man-machine interactive interface is developed. Then the machine tool is used to study the removal characteristics on machining parameters. It is indicated that the removal rate is not sensitive to processing time. When the angle between the polishing head and the workpiece is larger, the removal rate is higher. The surface roughness of workpiece can be less than 3 nm, which is machined by magnetorheological polishing with a small permanent magnet ball-end tool.