Method for refining stainless steel with high purity

Abstract

The present invention relates to a method of refining a stainless steel with high purity in where a raw material melted in an electric furnace is processed in an argon oxygen decarburization (AOD) refining furnace to be output to a ladle and then subjected to a continuous casting, wherein the occurrence of the refractory hard inclusion material is suppressed by controlling composition and basicity of the slag after the refinery surface reduction process and using the desulphurization process, so that ductility of the inclusion material can be improved and surface defects and cracks of a product can be prevented. The present invention provides a method of refining a stainless steel in where a raw material melted in an electric furnace is processed in an argon oxygen decarburization (AOD) refining furnace to be output to a ladle and then subjected to a continuous casting, wherein a basicity of a slag obtained after reduction process by using the argon oxygen decarburization (AOD) refining furnace is controlled to be in a range between 1.5 and 1.8, wherein a dolomite is used as a refractory material for the ladle, and wherein a composite (% Al 2 O 3 )+(% MgO) in the slag is less than 13.

What is claimed is:  
     
         1 . A method of refining a stainless steel in where a raw material melted in an electric furnace is processed in an argon oxygen decarburization (AOD) refining furnace to be output to a ladle and then subjected to a continuous casting, 
 wherein a basicity of a slag obtained after reduction process by using the argon oxygen decarburization (AOD) refining furnace is controlled to be in a range between 1.5 and 1.8,    wherein a dolomite is used as a refractory material for the ladle, and    wherein a composite (% Al 2 O 3 )+(% MgO) in the slag is less than 13.    
     
     
         2 . The method of refining a stainless steel according to  claim 1 , wherein the desulphurization process in molten steel is carried out between the electric furnace and the argon oxygen decarburization (AOD) refining furnace.  
     
     
         3 . The method of refining a stainless steel according to  claim 2 , wherein a ladle furnace is used to compensate for a temperature drop of the molten steel during the desulphurization process.