Research on the control technology of Ds inclusion and Oxygen content in GCr15 bearing steel

Abstract This paper presents a method for controlling Ds inclusions and oxygen content in bearing steel produced by EAT-LF-VD-CCM process, including EAF initial refining process, LF external refining process, VD vacuum treatment process and continuous casting production process. By reasonably reducing the basicity of slag, adjusting the amount and sequence of alloy addition, the carbon content of EAF steel is appropriately increased and the temperature of steel extraction is reasonably selected. Optimize the amount of deoxidizer added in off~furnace refining, improve the basicity of refining slag, control the vacuum time, aluminum loss and stirring volume; In the continuous casting process, middle alkaline coating agent, constant drawing speed and protective pouring process are used to control and remove Ds inclusions in bearing steel. The bearing steel produced by this process can remove big sized Ds inclusions in the steel, while the total oxygen content is controlled below 7ppm.