Effective, Controlled Method to Add Sulfur into Molten Steel to Produce Free Cutting Steel for Automobile

Abstract

In order to produce required free-cutting steel billets for auto industry, it is necessary to provide steel with correct content of sulfur. Effective, controlled method adding sulfur is very important in the production of sulfur free-cutting steel of consistent microstructure and hence mechanical properties and machinability. Because traditional methods of adding sulfur in steel can not provide stable results and always cause environmental pollution problems, the sulfur cored wire injection process was introduced. Stable results were obtained, and effects of parameters such as feeding rate, etc on sulfur recovery are investigated. The experimental results show that the mean recovery of sulfur was 80%, the treatment time of adding sulfur was about 2 minutes, and the refining period was shortened. Favorable metallurgical achievements and economical benefits were gained.