Improvement of cleanliness of 16 % Cr ferritic stainless steel in AOD processes

Abstract

The prediction of oxide phases in molten steel using commercial thermodynamic software showed the possibility of controlling the composition of inclusions in steel melts during Si deoxidation in AOD converter without the addtion of Al and Ti. Also, the apparent rate of alumina dissolution with different slags was investigated to minimize the inclusions originated from both deoxidation products and slag droplets. The CaO-SiO2-12%CaF2 slag system exhibits the highest rate of alumina dissolution. In plant tests, the surface defects of Fe-16%Cr cold rolled coils were significantly decreased by Si deoxidation in AOD converter, slag control and the optimized Ar bubbling in ladle treatment without using VD process.