Research On The Preparation Of Diamond Magnetic Abrasive And Its Finishing Performance

Magnetic abrasive particle has the abilities of magnetization and finishing, it can be applied to magnetic abrasive finishing of different materials when using different abrasives. Diamond abrasive has the characteristics of high hardness, sharpness, good wear resistance and high strength, etc., so diamond magnetic abrasive can be used to magnetic abrasive finishing of hard and brittle materials. However, the normally used sintering method and plasma spray method are not suitable to prepare diamond magnetic abrasive, because the high temperature of these methods can easily cause graphitization and inactivation of diamond abrasives. This study had an attempt to research on the preparation technology of diamond magnetic abrasive by electroless composite plating and the finishing performance of the prepared diamond magnetic abrasive. The main work and results are as follows:(1) The influence of load of iron powders, concentration of diamond abrasives, stirring speed, size of diamond abrasives on the relative content of diamond abrasive and the surface morphology of diamond magnetic abrasive were studied, and the effect of the heat treatment on the phases of the plating was analyzed. When the load of iron powders is 6g/L, the concentration of diamond abrasives is 4g/L, the stirring speed is 300r/min, the size of diamond abrasives is 1~2?m, the diamond magnetic abrasive with diamond abrasives of high relative content, uniformly dispersed, firmly bonded can be prepared.(2) The 2-D finite element model of static magnetic field for slotted permanent magnet pole was established, the influence of slot number, slot depth to width ratio, thickness of magnetic pole, finishing plate and loader on the surface magnetic field intensity and magnetic field gradient were simulated and analyzed, and the finishing tool for MAF equipment based on constant pressure was designed.(3) The effect of finishing pressure, finishing time, working table revolution, ethylenediamine concentration on material remove rate(MRR) and surface roughness were investigated by MAF experiment on flat quartz glass, and the influence of size of heat treatment temperature, diamond abrasive on finishing performance were researched. The results show that the prepared diamond magnetic abrasive has good finishing performance. The maximum MRR can reach to 2.326?m/min when using diamond magnetic abrasive with 3~5?m diamond abrasive. The surface roughness(Ra) of quartz glass can be rapidly reduced to 0.054?m from 0.709?m within 4min when using diamond magnetic abrasive with 1~2?m diamond abrasive.