Research On Rheological Behavior Of Mould Fluxes Under Electromagnetic Field

Along with the progress of the electromagnetic metallurgy technology, the electromagnetic field is increasingly widely used in the iron and steel metallurgy industry. For example, the quality of casting billet was improved and slab surface defects and internal defects were reduced because of the application of electromagnetic continuous casting technology. Meanwhile, as the metallurgical auxiliary materials, mould flux was of great importance for the technology of anterograde and slab quality in the process of continuous casting process. Under the environment of electromagnetic field, rheological properties in high temperature of mould flux which was silicate structure will be changed because of electromagnetic force.Research on the rheological properties of mould fluxes, especially under electromagnetic field, was still rare. Therefore, flow state of flux under the electromagnetic field was simulated by finite element software. The orthogonal test was designed and the experimental study was set up, using high temperature rotation vicosity instrument and electromagnetic characteristics test device. The relation curves for viscosity and temperature were drawn. The relationship among rheological property and Ca O/Si O2, the content of Na2 O, Mg O, Ca F2 and Ba O was researched, the viscous fluid activation energy was calculated on the basis of the equation of Arrhenius and the principle of least squares in order to providing theoretical basis for optimizing flux.The electromagnetic field and flow field was coupled in finite element software simulation, and electromagnetic force as a source of momentum was loaded into the fluid in the model, in order to describing the flow of the electromagnetic field under the condition of mould flux. Through simulation, electromotive force was induced in the electromagnetic field, and derivative was born induced current, lorentz force on the fluid particle was born because of the electromagnetic interaction, which could stir and promote the free flow of mould flux.And then the flow state was changed.Rheological behavior of mould fluxes under normal condition was measured by high temperature rotary viscosity meter. Viscosity and the fluid activation energy was decreased and the break temperature was risen with increasing Ca O/Si O2 and Na2 O content. But also viscosity and the viscous fluid activation energy and the break temperature decreased with increasing Mg O content and Ca F2 content and Ba O content, so flux would have wide temperature range with good liquidity.Rheological behavior of mould fluxes under Electromagnetic Field was measured by magnetic properties test equipment. The structure of the powder state was changed at the effect of electromagnetic force under electromagnetic field. With increasing Ca O/Si O2 and content of basic oxide, viscosity and the fluid activation energy and the break temperature was risen, which made flux have bad liquidity. And the longer the time of electromagnetic field, the larger viscosity. The lower temperature was, the bigger viscosity was.