Numerical Simulation Of Slag Composition Change Influence On ESR Process

There exist not only the temperature and flow field, also includes electric and magnetic fields in the ESR process. Regardless of which parameters change, other physical quantities will be affected, and ultimately the process of electro-slag metallurgy will be influenced. During the melting process, slag composition constantly changes, and these changes lead to variation of slag pool parameters. So these changes of conductivity, thermal conductivity, density and other parameters will affect ESR process. Under constant voltage and constant current operating conditions, heat balance of the molten pool will be affected by slag composition changes, and then depth and shape of molten pool will change. Thereby the smelting process will be influenced. So it’s important to study the effect of slag composition on remelting process.Based on field surveys and experimental determination, combined with site conditions, ESR process was simulated using by finite element analysis software ANSYS. From performance variation law of slag shell and slag pool(thermal conductivity, electrical conductivity and density), the effect of slag composition on ESR process was studied. Comparing the four situation: slag components have no changes, slag pool changes, slag shell changes, and slag shell and slag pool changes, temperature and electric field distribution differences of slag pool and ingots were suggested. This work can r improve ESR simulation accuracy and promote the optimization of ESR process for reference.Through the study the following main conclusions were derived:(1) As the smelting process progressed, conductivity of slag pool increases from 2.2308Ω-1cm-1 to 2.2859Ω-1cm-1; thermal conductivity of slag pool reduces from 2.2027 w.m-1K-1 to 1.9783 w.m-1K-1; density of slag pool decreases from 2.8765 g·cm-3to 2.8414 g·cm-3. The skull was considered as an insulator. From bottom to top, the conductivity of skull is 0Ω-1cm-1; thermal conductivity of skull from reduces from 1.7613 w.m-1K-1to 1.6847 w.m-1K-1; density of skull reduces from 2.8752 g·cm-3 to 2.8721 g·cm-3.(2) As the smelting process progressed, the maximum temperature of axial section for four situation is gradually increased. And the degree of temperature increase from high to low is: slag shell and slag pool changes, slag pool changes, slag shell changes, and slag components have no changes. The highest temperature difference of axial section between the both situations is up to 39 degrees Celsius, which are that slag shell and slag pool changes and slag components have no changes. Influence of slag pool on the axial section highest temperature is greater than the effect of crust changes.(3) With the smelting process, highest temperature of axial section rises, and temperature of central also increases. Outward along the radius of crystallizer, temperature gradually decreases, and the temperature gradually decreases under different conditions. Under different conditions, temperature change difference of skull is up to 8 degrees Celsius. Skull variations greatly influences on the temperature of crystallizer surface. And that is greater than the effect of slag pool. Then time is longer, and the impact is more significant.(4) Variations of slag pool and slag shell can make temperature of the center region and slag-metal interface increase, then expands slag molten pool region. Then solidification of ESR ingot will be affected. Then ingot is greater, the impact is greater.