Rheological Properties Test And Polishing Experimental Research Of Magnetorheological Gels-based Flexible Abrasives

With the miniaturization of the part structure and the complexity of the surface shape,it has become a challenge to finish the free-form surface in the limited space.At this stage,the finishing of the complex surface is mostly achieved by manual polishing.Magnetic abrasive finishing(MAF)and Magnetorheological finishing(MRF),as a new type of surface polishing technology,can achieve the polishing of complex shapes and obtain almost non-destructive surface quality.However,the traditional MAF and MRF have the disadvantages that the abrasive easily flies out of the processing area and the settlement stability is poor,respectively.Therefore,considering the shortcomings of traditional MAF and MRF,this paper proposes a preparation method of magnetorheological rubber-based flexible abrasive based on magnetorheological Gels(MRGs),testing and studying its rheological properties and polishing properties:.The main research contents of this article include:(1)Using methylcyclosiloxane and methylphenylcyclosiloxane as the main materials,and adding auxiliary additives such as end-capping agents and white carbon black,a silicone polymer macromolecule matrix was obtained.On this basis,MRGs and magnetorheological rubber-based flexible abrasives were prepared by adding Carbonyl iron powder(CIP)and Si C polishing powder,respectively,and the polishing mechanism was analyzed.(2)By varying the content of CIP and Si C polishing powders,MRGs and magnetorheological rubber-based flexible abrasives with different compositions were prepared,and their rheological properties and magnetorheological effects were tested by MCR-301.Through the time and magnetic field scanning under the condition of fixed strain 5% and magnetic flux density 0-1T,MRGs of different compositions and magnetorheological rubber-based flexible abrasives were tested.The results show that the magnetorheological effects of MRGs-30%,MRGs-40%,and MRGs-50% are44.4%,50.3%,and 67.3%,respectively.The magnetorheological effects of MRGs-30%-0.4g,MRGs-30%-0.5g,MRGs-30%-0.6g were 24.86%,18.05%,and 13.22%,respectively.The magnetorheological effects of MRGs-40%-0.4g,MRGs-40%-0.5g and MRGs-40%-0.6g were42.28%,34.09% and 22.17% respectively.MRGs-50%-0.4g,MRGs-50%-0.5g,MRGs-50%-0.6g under the above conditions were 64.24%,52.43%,46.95% respectively.(3)Using ANSYS Maxwell to simulate the magnetic field,a Φ20 ? 25 magnet was selected as the source magnetic field,and a set of flat workpiece fixtures for polishing is designed according to the shape and size of the workpiece and the experimental conditions possessed.The effects of the magnetic pole arrangement,magnetic pole speed S,polishing time t,feed rate F and other polishing conditions on the polishing effect of the magnetorheological rubber-based flexible abrasive werediscussed.When a single magnetic pole is used,the Magnetorheological Gels-based flexible abrasives have basically no polishing effect on flat workpieces.In the case of double poles,increasing the pole rotation speed S and polishing time t can obtain better surface quality,and blindly increasing the feed amount F can not achieve better surface quality.