Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuum induction furnace. It was found that the reaction interfaces of denitrification and Mn evaporation tend to migrate from the surface of slag layer to the surface of molten steel with the gradual exposure of molten steel during the vacuum slag refining process. Significantly, compared with the experimental group without slag addition, the addition of slag into steel can result in a lower Mn evaporation rate constant of 0.0192 cm·min⁻¹ at 370 Pa, while the denitrification rate is almost not affected. Besides, the slag has a stronger inhibitory effect on Mn evaporation than the reduced vacuum pressure. Moreover, the inhibitory effect of the slag layer on Mn evaporation can be weakened with the increase of the initial Mn content in molten steel. The slag layer can work as an inhibitory layer to reduce the Mn evaporation from molten steel, the evaporation reaction of Mn mainly proceeds on the surface of the molten steel. This may be attributed to the Mn mass transfer coefficient for one of reaction at steel/slag interface, mass transfer in molten slag, and evaporation reaction at slag/gas interface is lower than that of evaporation reaction at steel/gas interface. The introduction of slag is proposed for both denitrification and manganese control during the vacuum refining process of Mn steels.

考虑到高锰钢真空精炼的精确成分控制，在真空感应炉中通过真空渣精炼研究了锰钢从熔融锰钢中蒸发和脱氮的行为。发现在真空渣精炼过程中，随着钢水的逐渐暴露，脱氮和Mn蒸发的反应界面倾向于从渣层表面迁移到钢水表面。值得注意的是，与不添加炉渣的实验组相比，钢中添加炉渣可以降低 Mn 蒸发速率常数为 0.0192 cm·min ^-1在 370 Pa 时，反硝化率几乎不受影响。此外，炉渣对锰蒸发的抑制作用比降低的真空压力更强。此外，渣层对Mn蒸发的抑制作用可以随着钢水中初始Mn含量的增加而减弱。渣层可作为抑制层，减少钢水中锰的蒸发，锰的蒸发反应主要在钢水表面进行。这可能是由于钢/渣界面反应、熔渣中的传质和渣/气界面蒸发反应之一的Mn传质系数低于钢/气界面蒸发反应。