Performance evaluation of mechanically alloyed abrasives using maf process

Abstract

Surface finish is one the most critical quality measures in ceramics components. Now a day, grinding is one the most popular method of machining hard materials. An internal magnetic abrasive finishing process was proposed for producing highly finished inner surfaces of tubes used in critical applications including flow of gases or liquid piping systems. It uses a controlled magnetic force of extremely small magnitude on ferromagnetic abrasive particles which are combinations of abrasives and iron particles for the material removal. The process therefore is free from most of the ill-effects of conventional super finishing processes, which use hard grinding wheels that inflict micro-cracks, geometrical errors and distortions on the work surfaces. The process is widely used for ultra-fine polishing of very hard and brittle non- magnetic materials. Magnetic Abrasive Finishing (MAF) process is an advanced finishing process in which the cutting force is primarily controlled by the magnetic field. It minimizes the possibility of micro cracks on the surface of the ceramic tubes, due to control of low forces acting on abrasive particles. This process is able to produce surface roughness of nanometer range on internal and cylindrical surfaces. The MAF process offers many advantages, such as self-sharpening, self-adaptability, controllability, and the finishing tools. In MAF, the work piece is kept between the two poles of a magnet in the chuck and magnetic abrasives are placed inside the work piece. Magnetic Abrasive Particles (MAPs) composed of ferromagnetic particles and abrasive powder. The observed surface texture shows that the process is an accumulation of the micro-scratches from the abrasive cutting edges, generating a characteristic magnetic abrasive finished surface. This study presents the application of a new technique; magnetic field assisted finishing, for finishing of the inner surfaces of ceramic components. The experiments were performed on ceramic tubes to examine the effect of rotational speed, current,