1 Special Steel Institute, Central Iron and Steel Research Institute, Beijing 100081, China 2 College of Materials Science and Engineering, Chongqing University, Chongqing 400045, China 3 Central Laboratory, Central Iron and Steel Research Institute, Beijing 100081, China 4 Center for Fuel Cell Innovation, State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
Microstructure, hardness and contact fatigue properties of X30N high nitrogen stainless bearing steel
1 Special Steel Institute, Central Iron and Steel Research Institute, Beijing 100081, China 2 College of Materials Science and Engineering, Chongqing University, Chongqing 400045, China 3 Central Laboratory, Central Iron and Steel Research Institute, Beijing 100081, China 4 Center for Fuel Cell Innovation, State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
摘要 Microstructure, hardness and fatigue properties of X30N high nitrogen stainless bearing steel were investigated. It was found that nitrogen addition could effectively reduce the amount and size of coarse carbides. The original austenite grain size was obviously re.ned. Additionally, more retained austenite was found in X30N steel after quenching at 1050 C, which couldbe reduced from about 30% to about 6% by cold treatment at -73 Cand subsequent tempering, and thus, the ultimate hardness was increased up to about 61 HRC with reduction of austenite and precipitation of carbonitrides. Furthermore, the rolling contact fatigue lives of X30N steel are superior to those of 440C steel, which was attributed to the enhanced hardness and a certain retained austenite in the high nitrogen steel.
Abstract：Microstructure, hardness and fatigue properties of X30N high nitrogen stainless bearing steel were investigated. It was found that nitrogen addition could effectively reduce the amount and size of coarse carbides. The original austenite grain size was obviously re.ned. Additionally, more retained austenite was found in X30N steel after quenching at 1050 C, which couldbe reduced from about 30% to about 6% by cold treatment at -73 Cand subsequent tempering, and thus, the ultimate hardness was increased up to about 61 HRC with reduction of austenite and precipitation of carbonitrides. Furthermore, the rolling contact fatigue lives of X30N steel are superior to those of 440C steel, which was attributed to the enhanced hardness and a certain retained austenite in the high nitrogen steel.
XU Hai-Feng,GUILIN -Wu,YU Chang, et al. Microstructure, hardness and contact fatigue properties of X30N high nitrogen stainless bearing steel[J]. Journal of Iron and Steel Research International, 2018, 25(9): 954-967.
2018, Vol. 25 
