Effect of Slag Composition on the Oxidation Kinetics of Alloying Elements during Electroslag Remelting of Stainless Steel: Part-1 Mass-transfer Model

A new mathematical model for the computation of concentration changes occurring in electroslag remelting is proposed in order to study the oxidation behavior of titanium, aluminum, silicon in stainless steel. The solutions of the mass transfer are simultaneously calculated by penetration theory and film theory. In order to make the each system of Al+Al2O3, Si+SiO2, Ti+TiO2 and Fe+FeO reach the thermodynamic equilibrium at the slag-metal interface in the model, the molarity of FeO at the interface C-(FeO)* is employed, and then calculated by mass transfer balance for oxygen element. The ion and molecule coexistence theory is employed to investigate the effect of slag composition on the change of each alloying element. At the process of liquid metal film formation, metal droplet passing though the molten slag and metal pool, the fluxion of molten slag was considered into the mass transfer coefficient. Finally, the model was established using the software of Matlab. In theory, this model is suitable for all the chemical reaction of each element during the ESR process, and determines the change of concentration of each component both in metal and slag.