A novel magnetically driven polishing technique for internal surface finishing

Abstract

This paper presents a novel magnetically driven polishing tool for internal surface finishing. Differing from the existing magnetic abrasive finishing or magnetic field assisted finishing (MAF) methods; this new technique performs material removal inside a tube using a spherical magnet with abrasives driven by external bar magnets. This configuration of magnets not only simplifies the design but also allows more flexibility in the potential application to internal finishing of manifolds. The physical principle was introduced and polishing experiments were conducted to investigate the effect of magnetic abrasive particles and abrasive size based on the two major criteria of surface roughness and material removal. The results unequivocally substantiated the capability of the developed method with a more than 98% improvement in surface roughness for ring polishing and an 86% improvement for section polishing. An analytical model was devised to illustrate the material removal mechanism of the proposed internal polishing technique based on the experimental results. The technique developed in the paper shows signs of future success in finishing internal surface of complex components in a wide range of industrial applications.