DEVELOPMENT OF THE RH VACUUM METALLURGY F OR STEELS WITH EXTREMELY LOW-CARBON CONTENTS AT THE THYSSEN-STAHL-AG

Lowering of the carbon contents makes it possible to improve the formi ng properties and aging resistance of cold-rolled steels, and creates at the same time prerequisites for an improved surface as well as savi ng of titanium and niobium. The RH vacuum circulation process has cont ributed considerably within the framework of vacuum metallurgy to the development of steels with extremely low carbon content. Experiments f or the further development of the RH vacuum metallurgy at Thyssen in B eeckerwerth. Utilization of very large snorkel diameters at the treatm ent vessels as well as realization of exceptionally high carrier gas f low rates. Carbon contents below 10 ppm can be achieved. Deep-decarbur ized IF steels are mass-produced today. Description of the oxygen top blowing process in the RH vessel (RHO process), which was also develop ed by Thyssen.