Electrolytic magnetic abrasive finishing

Electrolytic magnetic abrasive finishing (EMAF) is a compound finishing process, involving traditional magnetic abrasive finishing (MAF) and an electrolytic process. The aim of including the electrolytic process into the EMAF system is to produce a passive film (or oxide film), which is much easier to remove than the original metal surface during processing. Moreover, in the presence of both electric and magnetic fields, the negatively charged ions move toward the anode surface along a cycloid curve by the action of the Lorentz force. Under appropriate operating conditions, this phenomenon promotes electrolytic effects, resulting in a further increase in finishing efficiency, yielding a superior surface. This study describes the principles of the process, the finishing characteristics of surface roughness and material removal, and the associated mechanisms. Experimental results show that the EMAF process yields quite excellent finishing characteristics, better than those obtained by MAF, especially with a high electrolytic current. The process parameters such as electrolytic current, electrode gap, magnetic flux density, and rate of workpiece revolution must be appropriately fitted to obtain a superior refined surface with high efficiency. (C) 2003 Elsevier Ltd. All rights reserved.