Optimization of Magnetic Abrasive Finishing Process
CHAPTER 1: INTRODUCTION
1. Magnetic Abrasive Finishing (MAF)
Surface roughness of parts produced by conventional machine tools, depends n the machine tool system and the cutting process. It is difficult to produce a smooth surface on complicated profiles at an economic cost by using conventional machining processes. This and the advent of new ‘ difficult-to-machine’ materials like hardened steel, nickel, cobalt, titanium alloys, ceramics, glass, etc., have necessitated the need for new machining techniques. Magnetic abrasive finishing is one such alternate process for improving the surface finish on complicated profiles at a reasonably low cost. It presents an attractive novel concept of surface and edge finish by abrasive particles. This process can overcome the limitations of traditional rigid shape grinding wheels in tackling complicate peripheries and may result in minimize induced stresses that usually come about by excessive penetration of hard grains in to the work surface. The process uses very low forces and loose abrasive particles and hence can minimize the damage during machining. In MAF, a flexible finishing action is sustained by the pressure exerted by a blanket of abrasive bonded to iron particles. This mixture is actuated by a magnetic field, which is coupled with rotational and oscillatory motions between flexible MAF brush and work piece. The finishing process is essentially accomplished without the need for designing expensive, rigid, vibration free machine tools by incorporating magnetic machining elements necessary cost of new equipment. MAF cutting agent is a composite of fine abrasive grits and coarser iron grains. The particles can thus be excited by a strong magnetic field to generate a normal dynamic pressure sufficient to refine the surface, deburr and chamfer its edges. Conventional abrasives like aluminum oxide (Al2O3) And silicon carbides (SiC) may be used as well as the costly super abrasives such as cubic
1. Magnetic Abrasive Finishing (MAF)
Surface roughness of parts produced by conventional machine tools, depends n the machine tool system and the cutting process. It is difficult to produce a smooth surface on complicated profiles at an economic cost by using conventional machining processes. This and the advent of new ‘ difficult-to-machine’ materials like hardened steel, nickel, cobalt, titanium alloys, ceramics, glass, etc., have necessitated the need for new machining techniques. Magnetic abrasive finishing is one such alternate process for improving the surface finish on complicated profiles at a reasonably low cost. It presents an attractive novel concept of surface and edge finish by abrasive particles. This process can overcome the limitations of traditional rigid shape grinding wheels in tackling complicate peripheries and may result in minimize induced stresses that usually come about by excessive penetration of hard grains in to the work surface. The process uses very low forces and loose abrasive particles and hence can minimize the damage during machining. In MAF, a flexible finishing action is sustained by the pressure exerted by a blanket of abrasive bonded to iron particles. This mixture is actuated by a magnetic field, which is coupled with rotational and oscillatory motions between flexible MAF brush and work piece. The finishing process is essentially accomplished without the need for designing expensive, rigid, vibration free machine tools by incorporating magnetic machining elements necessary cost of new equipment. MAF cutting agent is a composite of fine abrasive grits and coarser iron grains. The particles can thus be excited by a strong magnetic field to generate a normal dynamic pressure sufficient to refine the surface, deburr and chamfer its edges. Conventional abrasives like aluminum oxide (Al2O3) And silicon carbides (SiC) may be used as well as the costly super abrasives such as cubic
References: 1. Dhirendra k. Singh and V. Raghuram, 2004, Parametric Study of Magnetic Abrasive Finishing Process, Journal of Materials Processing Technology, pg.no.22-29 2 3. Dhirendra k. Singh, V.K.Jain, V. Raghuram and R. Komanduri, 2005, Analysis of Surface Texture Generated by a Flexible Magnetic Abrasive Brush, Wear, pg.no.1254-1261 4 5. Hitomi Yamaguchi and T. Shinmura, 1999, Study on Surface Modification resulting from Internal Magnetic Abrasive Finishing Process, Wear, pg.np.246-255 6 7. Hitomi Yamaguchi and T. Shinmura, 1999, Internal Finishing Process for Allumina Ceramic Components By Magnetic Abrasive Finishing Process, Precision Engineering, pg.np.135-142 8