铁路重载车轮间歇淬火的数值模拟与试验验证  

Numerical simulation and experimental verification of interrupted quenching(IRQ)for heavy-haul railway wheels

作　　者：姚三成 张建 刘学华[1,2] 赵海 史娜[1,2] 徐骏 YAO Sancheng;ZHANG Jian;LIU Xuehua;ZHAO Hai;SHI Na;XU Jun(Key Parts of Rail Transit Technology Innovation Center of Anhui Province,Maanshan 243003,Anhui,China;Technology Center,Maanshan Iron and Steel Co.,Ltd.,Maanshan 243003,Anhui,China;School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]轨道交通关键零部件安徽省技术创新中心,安徽马鞍山243003 [2]马鞍山钢铁股份有限公司技术中心,安徽马鞍山243003 [3]上海交通大学材料科学与工程学院,上海200240

出　　处：《钢铁》2023年第10期111-119,共9页Iron and Steel

基　　金：安徽省科技重大专项计划资助项目(202003a05020038)。

摘　　要：含马氏体(M)和贝氏体(B)的非珠光体混合组织层产生于铁路车轮热处理冷却过程,是一种潜在的行车故障源和危害源。针对非珠光体层十分突出的铁路重载车轮,基于软件MSC.Marc和Thermal Prophet建立了间歇淬火(IRQ)有限元数值模型,分析了IRQ工艺对车轮热处理温度场及组织性能的影响,并进行了实物验证。计算结果表明,在短时的淬火中断期间,因受到轮辋内部更深处的热传导影响,踏面近表层产生“温度小平台”或回温现象,回温温度低于临界点Ac1,可避免出现二次奥氏体化,但踏面次表层及轮辋内部受影响甚微。IRQ工艺使车轮踏面近表层的温降有所减缓,避开大部分M和B组织转变区域,抑制了非珠光体组织的形成,将非珠光体层厚控制在6 mm以内,显著改善热处理冷却后踏面附近的组织状态;轮辋内部为较均匀一致的细珠光体和少量铁素体(P-F)组织,但在距踏面表面10~15 mm的深度范围内,组织组成可能会出现局部波动,在P-F组织中又重新生成少量的B组织。自踏面向下,车轮的强硬度梯度分布合理、平缓递减,轮辋内部绝大部分区域的强硬度水平未受到明显影响,且因为“预冷效应”,IRQ工艺使距踏面表面15~30 mm的深度范围内的平均有效冷却速度有所提高,形成了局部的强硬度极大值区,较传统工艺车轮的强硬度略有提高。实物验证结果与计算结果基本一致。经综合评判,在控制车轮非珠光体层方面施用IRQ工艺基本可行。The non-pearlite mixed microstructure layer containing martensite(M)and bainite(B),which is generated during the heat treatment cooling process of railway wheels,is a potential source of driving faults and hazards.For heavy-haul railway wheels with prominent non-pearlite layer,the finite element numerical model of interrupted quenching(IRQ)was established based on software MSC.Marc and Thermal Prophet,and the influence of IRQ process on temperature field,microstructure and mechanical properties of the wheel was analyzed,and the physical verification was carried out.The simulation results show that during the short quenching interruption period,due to the influence of heat conduction inside the deeper rim,a small temperature platform or temperature return phenomenon occurs near the surface of the wheel tread.The return temperature is lower than the critical point Ac1,which can avoid secondary austenitization,but the tread sub-surface and inside of the rim are slightly affected.IRQ process slow down the temperature drop near the tread surface,and avoid most of the M and B transformation areas.The non-pearlitic layer is inhibited,and its thickness is controlled within 6 mm,so the microstructure near the tread is significantly improved.The interior of the rim has a relatively uniform microstructure with fine pearlite and a small amount of ferrite(P-F),but within a depth range of 10-15 mm from the tread surface,the composition of the microstructure may fluctuate locally,and a small amount of B microstructure may be regenerated in the P-F microstructure.The gradient of strength and hardness distribution from the tread surface of the wheel is reasonable and gradually decreased,and the strength and hardness level of most areas inside the rim is not significantly affected.Due to the pre-cooling effect,the IRQ process improves the average effective cooling rate within the depth range of 15-30 mm from the tread surface,forming a local maximum area of strength and hardness,slightly improving the strength and hardness compare

关 键 词：重载车轮 间歇淬火 欠速冷却 非珠光体层 多场耦合 

分 类 号：U270.6[机械工程—车辆工程] TG156.3[交通运输工程—载运工具运用工程]