Inclusion generation and evolution of 38CrMoAl steel in refining process
GENG Xin1, SONG Bo1, LIU Tao2, CHEN Yong-feng2, XU Guo-fang1, HUANG Yan2
1. School of Metallurgy and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 2. Steelmaking Department, Wuhu Xinxing Ductile Iron Pipes Co., Ltd., Wuhu 241000, Anhui, China
Abstract：Due to non-metallic inclusions in steel exceeding the standard when smelting 38CrMoAl high alumina steel in a domestic plant, the problem that steel quality is not up to standard is occurred occasionally. Industrial trials for the steel were conducted using the "converter (LD)-LF refining (aluminum deoxidation and alloying, high alkalinity slag refining)-RH vacuum refining-soft blowing-continuous casting" process flow.In order to better remove the non-metallic inclusions in the steel, the industrial test was conducted using the graded segment sampling method to sample the non-metallic inclusions in the steel, so as to investigate the generation causes of non-metallic inclusions in the steel and their evolution.The results show that the high alkalinity slag refining can effectively reduce the mass fraction of Al2O3 in the inclusions and modify them to calcium-magnesium-aluminate inclusions. The average composition of inclusions falls within the liquid phase line during RH soft blowing.
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2022, Vol. 32 
