Finishing Mechanism And Experiments Study Of Viscoelastic Magnetic Abrasive

Upgrade and development of the equipment manufacturing industry have close relation with the progress of advanced manufacturing technology. As a kind of advanced manufacturing technology, the surface finishing technology received more and more widely attention. With its special finishing mechanism and method, magnetic abrasive finishing processing which is an important branch of surface finishing technology, is widely used to finishing many components which traditional finishing methods cannot finishing. In order to promote the application of magnetic abrasive finishing processing, it is important to research and develop a kind of magnetic abrasive which is characterized with simple process, good finishing effect and low cost. At the same time, it is also the starting point of this paper.Viscoelastic magnetic abrasive which has advantages of good liquidity, adaptability, high machining accuracy and simple preparation method, it can solve the problem that slender tube, ladder hole, blind hole, cross hole and slightly grooved surface can not solve. The main research contents of the article as follows:1. Non-Newtonian fluid was preliminary classified. The viscoelastic magnetic abrasive was determined as a kind of Bingham fluid. The related mechanical model was established, which is used to analyze the mechanical properties of Viscoelastic magnetic abrasive.2. Rheology theory was used to analyze rheological phenomenon of viscoelastic magnetic abrasive in the magnetic field. Main factors influencing the abrasive viscosity have been found, including magnetic field intensity, viscosity of the carrier and volume ratio of solid particle. Moreover, forces of single abrasive particle in the finishing state were analyzed. Finally, on the basis of micro grinding theory, the finishing mechanism of viscoelastic magnetic abrasive was expounded in the paper.3. First of all, liquidity, adhesion, storage stability and preparation complexity of viscoelastic magnetic abrasive were analyzed and compared. Then, polydimethylsiloxane rubber and silicone-boron polymer were selected as carrier of viscoelastic magnetic abrasive. At last, the preparation principles and methods of viscoelastic magnetic abrasive were introduced.4. Firstly, through orthogonal experiments, the composition proportion of polydimethylsiloxane rubber carrier were found:5%insulating oil,4%oleic acid,2%silicone oil,1%plasticizer. Composition of abrasive was optimized by orthogonal experiment and the best ingredient ratio was found:the quality ratio of iron powder and silicon carbide is3:1, silicon carbide mesh is200, iron powder mesh is100,30%carrier quality accounted for abrasive.5. Two kinds of viscoelastic magnetic abrasive were used to finishing Titanium alloy (TC4) and Magnesium alloy (AZ31B). After15minutes, Titanium alloy surface roughness reduced from Ra0.63μm to Ra0.282μm. After10minutes, Magnesium alloy surface roughness reduced from Ra0.983μm to Ra0.352μm. The abrasive finishing performance to Titanium alloy and Magnesium alloy was verified.