Analysis on modification behavior of rare earth to inclusions in high clean bearing steel
DONG Da-xi1, YANG Chao-yun2, HU Yun-sheng1, LUAN Yi-kun2, YANG Hua-feng1, ZHAO Rui-hua1
1. Shisteel Company, HBIS Group, Shijiazhuang 050031, Hebei, China; 2. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, Liaoning, China
Abstract:To clarify the modification behavior of rare earth to inclusions in high clean bearing steel, and then optimize the rare earth treatment process of bearing steel, high-purity RE alloy was added into high clean bearing steel, and inclusions and their precipitation behaviors in bearing steels with different RE contents were characterized and analyzed using scanning electron microscopy, energy disperse spectroscopy and electron probe microanalysis. The results show that the trace amount of RE can preferentially modify elongated MnS inclusions into RE3S4 particles under the condition of the incomplete modification of inclusions in bearing steel. And RE3S4 inclusions can not only form independently or at the nuclei of Al2O3 inclusions during the steelmaking process, but also precipitate together with MnS inclusions in the form of RE3S4·yMnS (y<1) complicated inclusions during the solidification process, also taking Al2O3 inclusions as the nuclei. With the increase of RE content, the reaction sequence of RE elements with inclusion forming elements should be O, S, As, P and C successively under the condition of the complete modification of Al2O3 and MnS inclusions, and the evolution sequence of inclusion type is expected to be RE2O3, RE2O2S, RES, RE-S-As, RE-As(-P)/RE-O-As(-P), RE-P-C/RE-O-P(-C) and RE-O-C.
董大西, 杨超云, 胡云生, 栾义坤, 杨华峰, 赵瑞华. 高洁净轴承钢中稀土变质夹杂物行为分析[J]. 中国冶金, 2020, 30(6): 30-38.
DONG Da-xi, YANG Chao-yun, HU Yun-sheng, LUAN Yi-kun, YANG Hua-feng, ZHAO Rui-hua. Analysis on modification behavior of rare earth to inclusions in high clean bearing steel[J]. China Metallurgy, 2020, 30(6): 30-38.
LIU Y Q,WANG L J,CHOU K C. Effect of cerium on the cleanliness of spring steel used in fastener of high-speed railway[J].Journal of Rare Earths,2014,32(8):759.
[7]
WANG H P,XIONG L,ZHANG L,et al. Investigation of RE-O-S-As inclusions in high carbon steels[J]. Metallurgical and Materials Transactions B,2017,48(6):2849.
[8]
YANG C Y,LUAN Y K,LI D Z,et al. Effects of rare earth elements on inclusions and impact toughness of high-carbon chromium bearing steel[J]. Journal of Materials Science & Technology,2019,35(8):1298.
LI Y D,LIU C J,ZHANG T S,et al. Liquid inclusions in heat-resistant steel containing rare earth elements[J]. Metallurgical and Materials Transactions B,2017,48(2):956.
[15]
PAN F,ZHANG J,CHEN H L,et al. Thermodynamic calculation among cerium,oxygen,and sulfur in liquid iron[J]. Scientific Reports,2016(6):35843.
[16]
Waudby P E. Rare earth addition to steel[J]. International Metals Reviews,1978(2):74.
[17]
Adabavazeh Z,Hwang W S,Su Y H. Effect of adding cerium on microstructure and morphology of Ce-based inclusions formed in low-carbon steel[J]. Scientific Reports,2017(7):46503.
[18]
XIN W B,SONG B,SONG M M,et al. Effect of cerium on characteristic of inclusions and grain boundary segregation of arsenic in iron melts[J]. Steel Research International,2015,86(12):1430.
Hufenbach J,Helth A,Lee M H,et al. Effect of cerium addition on microstructure and mechanical properties of high-strength Fe85Cr4Mo8V2C1 cast steel[J]. Materials Science and Engineering A,2016(674):366.