Abstract: Bearing steel inclusions produced by BOF-LF-RH-CC and EAF-LF-VD-CC were compared and analyzed by taking two different bearing steel production processes of a company as an example. The furnace tapping at the beginning of the carbon content of the early stage of the LF refining effect on the number of inclusions as well as the composition, the carbon mass fraction of steel for 0.07 % in the BOF,LF refining the early inclusion and quantity for 5.04 per mm2 was mainly for Al2O3 inclusions, the carbon mass fraction of steel for 0.58 % in the EAF, LF refining the early inclusion and quantity for 2.49 per mm2 was mainly for MgO·Al2O3 style inclusions, but at the end of the LF refining steel carbon content have less effect on the number of inclusions. CaO activity in LF refining slag has an impact on CaO content in inclusions. LF refining slag of BOF-LF-RH-CC process has an CaO activity of 0.632, and the CaO mass fraction in inclusion is 5 % at the end of refining. The CaO activity of LF refining slag in EAF-LF-VD-CC process is 0.965, and the CaO mass fraction of inclusion at the end of refining is 18 %. By comparing and analyzing the composition and quantity changes of bearing steel inclusions after RH and VD, it is found that the number of MgO·Al2O3 high-melting point inclusions decreases from 1.02 per mm2 to 0.01 per mm2 after RH. MgO･Al2O3 style high melting point inclusion quantity by 0.18 per mm2 was reduced to 0.01 per mm2 after VD and inclusions are mainly low melting point of CaO-Al2O3, but from CaO-Al2O3-MgO style class inclusion quantity analysis found on RH treatment after a sharp decline in the number of inclusions and inclusions after VD amount is not large drop, think of VD process of MgO･Al2O3 style inclusions decrease of slag due to sharp steel slag mix at VD process of MgO·Al2O3 style disguised “calcium treatment” results.

Key words: bearing steel, inclusions, RH, VD