| Electromagnetic fields are used more and more widely in the continuous casting process,especially electromagnetic stirring technology.Most of them use low-frequency magnetic fields,but at present there are few related studies on the influence of low-frequency magnetic fields on mold flux.Since the low frequency magnetic field also affects the heat,mass and energy transmission of the slag,the performance of the slag is changed,thereby affecting the lubrication behavior of the slag.Therefore,based on the experimental test of the conductivity of the mold flux,the numerical simulation software ANSYS is used to study the influence of the low frequency magnetic field on the lubrication behavior of the mold flux.It is of great theoretical and practical value to fully understand the influence of electromagnetic field on the performance of molten mold flux,develop electromagnetic continuous casting technology,perfect the design theory of mold flux,and optimize the performance of mold flux.The main conclusions drawn are as follows:?1?The conductivity of the molten slag increases with increasing temperature and increases with increasing alkalinity.The relationship between the conductance energy E and the optical alkalinity is:E=1388.316?=-923.756;The relationship between composition and conductivity is:k/(S·cm-1)=xx(0.001?T-1673?;among them xx=-1.676 x?Al2O3?(2.641x?MgO?(3.223x?CaF2?(1.879x?Na2O?.The effect of the composition on the conductivity of the molten slag is:Na2O>CaF2>Al2O3>MgO.?2?The magnetic induction intensity of the mold flux of the transverse layer and the longitudinal layer in the crystallizer increases with the increase of the current intensity,and decreases with the increase of the magnetic field frequency;The electromagnetic force received increases as the current intensity increases,and increases as the magnetic field frequency increases.The magnetic induction intensity and electromagnetic force of the mold flux of the transverse layer are at the center of the electromagnetic stirrer,and gradually decrease toward both ends,and the overall distribution is"large in the middle,small in both ends";The magnetic induction intensity and electromagnetic force of the mold flux of the longitudinal layer are both near the wall of the crystallizer and gradually weaken toward the center.?3?The low frequency magnetic field affects the flow behavior of the mold flux at the meniscus,forming a vortex in the meniscus region.Changing the current intensity of the low-frequency magnetic field mainly changes the flow velocity of the molf flux at the meniscus.When there is no low-frequency magnetic field,the maximum velocity of the protective slag is 0.035 m/s,after applying the low frequency magnetic field,the maximum speed of the mold flux gradually increases from 0.0355 m/s to 0.038 m/s as the current intensity increases.Changing the frequency of the magnetic field mainly changes the flow direction of the mold flux at the meniscus.As the frequency increases,the more vortices formed in the mold slag area.?4?Increasing the current intensity or the magnetic field frequency reduces the mold flux consumption value at each moment in a vibration period and increases the time of negative consumption.After applying the low-frequency magnetic field,the time for the mold flux to flow into the slag channel is 0.27s-0.346s,which is 10.75%-30%lower than that 0.37s without low frequency magnetic field,so the low-frequency magnetic field weakens the lubricating properties of the mold flux.And the relationship between the average slag consumption of the crystallizer low frequency magnetic field in a vibration cycle is as follows:Q=285.38145-47.51256f-1.42527I+0.23749If. |
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