Research On Preparation And Properties Of Iron MRF From Iron Scale

Magnetorheogical Fluid is a new type of smart materials, composed of carrier liquid, soft magnetic particles, and additives. It has fluid characteristics and the characteristics of intelligent control, and its rheology can occur rapidly reversible changes and has a greater shear stress under the external magnetic field. It can be applied to the clutch, tumor treatment, magnetorheological finishing, shock absorbers, and so on. The study of magnetorheological fluid has become a new field of materials science. At present, we usually use carbonyl iron powder as the soft magnetic particle in magneto-rheological fluid, but due to the higher cost of carbonyl iron powder preparation, which limits the applications of magneto-rheological fluid in a wide range of industrial. In this paper, iron scale uses as oxide raw materials, which is solid waste generated in steel production. Smash the iron scale porphyrization and ball milling, and then use the hydrogen to reduce to the micro-reduced iron powder. Make iron powder obtained mix with appropriate silicone oil for the prepareation of reduced magnetorheogical fluid and study its performance. So that we can achieve the high value-added steel-making use of waste, have a greater research value.In this paper, abtain the iron oxide powder by iron scale ball milling, pre-processing filter, and then the use XRD, SEM, Mosbauer spectrum to character the samples. The results show that the former iron oxide scale contains large amounts of water and oil, in the process of milling it is easy to agglomerate, influence the effect of milling. So we use the method of foil firstly and then the dry cleaning, multiple ball-millings, screening out large particles, and finally get the iron powder of a good size and shape.The SEM observation of iron oxide powder shows it is basic for the rod-shaped and spherical. At650℃reduction by4h, the reduction of the iron content of iron up to98%, by the Mosbauer spectrum analysis, iron is up to93.593%, content of Fe-N solid solution is6.407%. Reduced iron powder is the gray color in our experiment, bulk density is0.66g/cm3. The saturation magnetization of reduced iron powder by measuring is Ms=225.7emu/g; coercive force:Hc=6.01Oe; residual magnetization:Mr=0.261emu/g. According to the containing liquid choice, we chose the silicone oil as a carrier; silane coupling agent KH-550as surfactants to coat on the reduced iron powder. Before and after coated iron powder find that post-coated iron powder is more easily dispersed in the liquid contained, and has a good settlement stabilization in the liquid contained. Test the viscosity of magnetorheogical fluid and mechanical properties throgh MCR301rheometer. The test results show that magnetorheogical fluid has taken place a clear shear-thinning phenomenon under the zero-field and magnetic field which is a typical non-Newtonian fluid. Magnetorheogical fluid shear stress rapidly increases with the magnetic field. The shear stress of magnetorheogical fluid can increase by add Fe2O3nanoparticles, and improve the stability of the settlement. The addition of organobentonite not only increase the magnetorheogical fluid viscosity, but also greatly enhanced the stabilization of settlement for magnetorheogical fluid.