Study On The Effect Of Slag Composition Continuous Change In ESRto Solidification Process By Numerical Simulation

The electro-slag remelting (ESR) process is a process that are closely related toelectric field, flow field, temperature field and magnetic field. The changes of anyparameters will impact to others and have an effect on remelting process. In practicalESR process, the composition of slag is changing, and the thermal properties of slagpool is undergoing change as a result.A layer of slag is formed between ingot andcrystallizer during the process. Owing to changes of composition of slag pool,composition of slag crusts will changewith the height increase. Thermal conductivityalso varies along its height. The variation of thermal properties of slag crusts and slagpool will affect the ingot quality and, economic and technical indicators. Therefore, it isvery significant to research the effect of variations of the composition of slag crusts andslag pool during ESR.Based on the results of the domestic and foreign researches, what the changes ofslag composition impact of ESR process is studies on the performance variation of theslag pool and slag shell (thermal conductivity, thermal conductivity and electricalconductivity changes of slag shell) by employing the software ANSYS. Comparing twosituations that slag composition is changed or not, this paper shows the differences oftemperature distributions of metal bath and ESR ingot, pool shape, and current density.These works can provide references to further improve the accuracy of the simulationand optimize ESR remelting process.The following main conclusions are obtained by research:1) Thermal conductivity is reduced along with the increase of slag shell thickness,from bottom up. At the same time,temperature raises in slag pool and moltenpool. When the filling ratio of model is0.5, the highest temperature is higher thanindeclinable thermal conductivity at3600s and the value is30℃.2) The decrease of the thermal conductivity, along with the increase of slag shellthickness,from bottom up.lead to temperature increase in the ESR process, and themaximum temperature1975℃can be obtained in center of slag pool. When thermalconductivity of the slag shell along with the increase of slag shell thickness,from bottomup.at the same time, thermal conductivity and resistivity of slag pool are reduced, thetemperature is decreased in the ESR process. The maximum temperature is lower thanindeclinable thermal conductivity at3600s and the value is68℃. But the difference oftemperature is very small near the slag shell.3) Three situations were simulated for the ESR process. The first is that thethermal conductivity of slag shell varies from button to the top. The second is that thethermal conductivity of slag shell varies from button to the top, the thermal conductivityof slag pool and resistivity is reduced. The third is that all of the parameters areindeclinable. The results shows that while the molten pool of the first one is the deepest,the most shallow molten pool appears in the second simulation.