G23Cr2Ni2Si1Mo钢制表层纳米贝氏体渗碳齿轮组织及性能  

Microstructure and properties of carburized G23Cr2Ni2Si1Mo gear with nano-bainite surface

作　　者：乔建勇 文超 宋倩 赵文胜 QIAO Jianyong;WEN Chao;SONG Qian;ZHAO Wensheng(CRRC Qishuyan Institute Co.,Ltd.,Changzhou,Jiangsu 213011,China)

机构地区：[1]中车戚墅堰机车车辆工艺研究所股份有限公司,江苏常州213011

出　　处：《轨道交通材料》2024年第3期23-27,共5页MATERIALS FOR RAIL TRANSPORTATION SYSTEM

摘　　要：在轨道交通机车齿轮生产工艺中引入纳米贝氏体钢热处理制备技术,以G23Cr2Ni2Si1Mo钢为研究对象,利用SEM、TEM、硬度、力学性能、滚动接触疲劳等研究其扩散碳势为0.65%和0.85%时等温淬火制备的表层纳米贝氏体渗碳齿轮的组织及性能,并与常规18CrNiMo7-6钢油淬制备的表层细针马氏体渗碳齿轮进行横向对比。结果表明:G23Cr2Ni2Si1Mo钢制的某型轨道交通用机车主动齿轮在扩散碳势为0.85%,等温淬火温度200℃保温8 h最佳。微观组织满足相关标准要求,表层最高硬度可达(700±10)HV1,距表层0.3 mm处纳米贝氏体板条厚度约为69 nm,基体力学性能相比于18CrNiMo7-6钢油淬制备的表层细针马氏体渗碳齿轮,塑性、韧性在同一水平的情况下,强度高出约13%,滚动接触疲劳额定寿命L_(10)与中值寿命L_(50)分别提高40%和29%。The heat treatment preparation technology for Nano-bainite steel is introduced into the production of gears on rail transit locomotives.By taking G23Cr2Ni2Si1Mo steel as the research object,the microstructure and properties of the carburizing gears with surface nano-bainite prepared by isothermal quenching at the diffusion carbon potential of 0.65%and 0.85%are studied with the help of SEM,TEM,hardness,mechanical property and rolling contact fatigue test,and a parallel comparison is made with the 18CrNiMo7-6 carburized gear with surface fine-needle martensite prepared by conventional oil quenching.The results show that G23Cr2Ni2Si1Mo steel driving gear for a rail transit locomotive can achieve the best performance at the diffusion carbon potential of 0.85%and a isothermal quenching temperature of 200℃for 8 h.The microstructure meets the requirements of relevant standards with the maximum hardness of the surface layer up to(700±10)HV1,and the thickness of the nano-bainite slats is about 69 nm at the depth of 0.3 mm from the surface layer.Compared with the surface fine-needle martensitic carburized gear prepared by oil quenching of 18CrNiMo7-6 steel,if the mechanical properties of the matrix are at the same level of plasticity and toughness,the strength is about 13% higher,and the rated rolling contact fatigue life L_(10) and the median life L_(50) are 40% and 29%higher,respectively.

关 键 词：纳米贝氏体 渗碳齿轮 等温淬火 滚动接触疲劳 

分 类 号：U260.332[机械工程—车辆工程] U270.4[交通运输工程—载运工具运用工程]