Experimental investigation and kinetics model ware carried out to study the effect of the atmosphere on the desulfurization of low-sulfur plastic die steel during the electroslag remelting process. 55Cr17Mo1VN plastic die steel was applied as the electrode and remelted with two different kinds of atmospheres using a laboratory-scale ESR furnace. It was found that the sulfur content of 50 ppm in the electrode decreased to 8–12 ppm in the air atmosphere, while reduced to 9–14 ppm in a protective atmosphere. The desulfurization rates were 82% and 78%, respectively. Correspondingly, the sulfur content of 0.12% in initial slag increased to 0.125% and 0.15%. The coupled desulfurization kinetics model was established, the oxygen activity (a_O) and sulfur distribution coefficient (L_s) are taken into consideration, and they change with the remelting time during the calculation. The results show that the calculated values are in good agreement with the experimental values. The desulfurization effect at the electrode tip is significantly better than the positions where the droplet passes through the slag layer and the slag pool/molten pool interface. The L_s and comprehensive mass transfer coefficient of sulfur (k_S^*) decrease with the remelting time, while the a_O at each reaction position increases. Compared with the protective atmosphere, L_s and k_S^* have larger values during the air atmosphere ESR process, but the a_O value is equal. Under the different atmospheres, the most types of inclusions in the steel are MnS, and the refining atmosphere has no significant effect on the types of inclusions.

通过实验研究和动力学模型研究了气氛对电渣重熔过程中低硫塑料模具钢脱硫的影响。使用55Cr17Mo1VN塑料模具钢作为电极，并使用实验室规模的ESR炉在两种不同的气氛下重熔。发现在空气中，电极中硫的含量为50 ppm，降至8–12 ppm，而在保护性气氛中，硫含量降至9–14 ppm。脱硫率分别为82％和78％。相应地，初始炉渣中的硫含量为0.12％，分别增加到0.125％和0.15％。建立了脱硫动力学耦合模型，氧活度（a _O）和硫分布系数（L_s）被考虑在内，它们在计算过程中随重熔时间而变化。结果表明，计算值与实验值吻合良好。电极尖端的脱硫效果明显好于液滴穿过熔渣层和熔渣池/熔池界面的位置。硫的L _s和综合传质系数（k _S ^*）随着重熔时间的增加而降低，而每个反应位置的a _O则增加。与保护气氛相比，L _s和k _S ^*在大气ESR过程中具有较大的值，但是a _O值相等。在不同的气氛下，钢中夹杂物最多的是MnS，而精炼气氛对夹杂物的类型没有显着影响。