Effects of rare earth elements on inclusions and impact toughness of high-carbon chromium bearing steel

作     者：Chaoyun Yang Yikun Luan Dianzhong Li Yiyi Li 

作者机构：Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2019年第35卷第7期

页      面：1298-1308页

核心收录：

学科分类：08[工学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos. U1508215 and U1708252) the National Key Research and Development Program (No. 2016YFB0300401) 

主　　题：High-carbon chromium bearing steel Rare earth Inclusions Impact toughness 

摘      要：High-carbon chromium bearing steels with different rare earth (RE) contents were prepared to investigate the effects of RE on inclusions and impact toughness by different techniques. The results showed that RE addition could modify irregular Al2O3 and MnS into regular RE inclusions. With the increase of RE content, the reaction sequence of RE and potential inclusion forming elements should be O, S, As, P and C successively. RE inclusions containing C might precipitate in molten steel and solid state, but the precipitation tem perature was significantly higher than that of carbides in high-carbon chromium bearing steel. For experim ental bearing steels, the volume fraction of inclusions increased steadily with the increase of RE content, but smaller and more dispersed inclusions could be obtained by 0.018% RE content compared with bearing steel without RE, whereas the continuous increase of RE content led to an increasing trend for inclusion size and a gradual deterioration for inclusion distribution. RE addition could improve the transverse impact toughness and isotropy of bearing steel, and for modified highcarbon chrom ium bearing steel by RE alloying, the increase of RE content continuously increased both transverse and longitudinal im pact toughness until excessive RE addition.