Magnetic abrasive finishing (MAF) is a polishing/finishing technique used primarily to achieve higher levels of surface finish. The process is widely used for finishing of very hard and brittle nonmagnetic materials. It utilizes magnetic force and ferromagnetic abrasive particles for finishing of work piece. Ferromagnetic particles are conglomerate of abrasives and iron particles. In MAF set up used in present work, the work piece to be finished internally is kept between two poles of a magnet. The magnetic abrasive particles are placed inside the stainless steel tube to be polished/ finished. The magnetic abrasive particles join each other forming a magnetic abrasive flexible brush in the work piece due to the force applied by the magnetic poles. This brush behaves like a multi-point cutting tool for the finishing operation. The work piece was a non-magnetic brass tube. The magnetic abrasive particles used in present work were prepared chemically of iron and diamond particles. The input parameters which were considered for the study include rotational speed of poles, working gap, MAP size, quantity of abrasive particles. The range of parameters had been decided by preliminary experimentation and literature review. The effect of MAF parameters have been studied on Percentage Improvement in Surface Finish. The working gap, MAP size and interaction of rotational speed & MAP size have shown predominant effect on the percent improvement in surface finish. Then the SEM analysis of the finished work pieces was done which indicates that the tool marks are completely removed by the MAF process. The maximum PISF (69) was obtained at gap = 3 mm, speed = 575rpm, MAP size = 163µm and weight = 6gm.

Keywords : magnetic abrasive finishing; diamond particles; etc.