Study And Application Of Magnetic Abrasive Finishing

In this dissertation, the theory and experiment on magnetic abrasive finishing (MAF) is studied. Especially, studied and analyzed of MAF on the inner cylinder surface processing, and designed the magnetic work reamer and part suit for the inner surface processing.The major works can be divided into three parts:1. A theoretical study on MAF(1) The study on the processing mechanism of magnetic abrasive finishing. Based on the applied force analysis and kinematic analysis of a single magnetic abrasive grain and the applied force analysis of achieved by the combined action of micro-cutting, extruding, plastic deforming, chemical corroding and electrochemical wearing. Other important factors, which affect the finishing performance, such as heat generated by cutting, self-sharpening, terminal velocity of the splashing grains, as well as dry and wet abrasive were also investigated. Specially, analyzing the characteristics of the internal cylinder surface by MAF and researching the internal cylinder surface manufacturing theory of ferromagnetic material especially, at the same time, the critical speed formula is deduced.(2) The analysis of the major performance parameters for magnetic abrasive finishing quantitatively. The surface roughness Ra and the mount of metal removed M, which are the most important performance parameters, were studied quantitatively and then their mathematic models were developed and validated by the experimental results. Using the models to predict the products' quality could eliminate many midway tests and complicated monitors and avoid over machining, thus the machining efficiency could be increased. And using the Matlab analyzed these data.2. An experimental study on MAF(1) The experimental study on the effects of various factors on the performance of magnetic abrasive finishing during the process. The factors studied are machining clearance, machining time, rotating speed of the magnetic pole, the composition and size of the magnetic abrasive gains, and type of abrasive grease. A series of experiments were conducted and the changing curves and best values of each factor on the performance were determined. The experimental results could be used as a guide for the practical application of the magnetic abrasive finishing.(2) The experimental study on the effects of unbonded abrasive. The unbonded magnetic abrasive is composed of the iron or steel powder with SiC powder of different size, and its no adhibited, only uses a little machine oil, and getting a good working result.3. Designed of magnetic work reamer and studied on experimentIn this paper, we designed the magnetic work reamer and process, which be adopt to work on big size of thickness inner surface of ferromagnetic material, and studied the phenomenon of the magnetism-shield.