高速列车铸钢与锻钢制动盘CCT曲线测定与分析  

Determination and analysis of CCT curves of cast steel and forged steel brake disc for high-speed train

作　　者：李志强[1] 张晓康 刘志成 杨智勇[1] 李卫京[1] LI Zhiqiang;ZHANG Xiaokang;LIU Zhicheng;YANG Zhiyong;LI Weijing(School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学机械与电子控制工程学院,北京100044

出　　处：《中南大学学报（自然科学版）》2023年第9期3453-3460,共8页Journal of Central South University:Science and Technology

基　　金：中央高校基本科研业务费专项资金资助项目(2021JBM023);国家自然科学基金资助项目(52002018)。

摘　　要：为明确高速列车铸钢制动盘与锻钢制动盘材料的组织转变特性,采用DIL 805L型热膨胀仪测定高速列车用铸钢制动盘与锻钢制动盘用低合金钢材料的过冷奥氏体连续冷却转变特性并绘制CCT曲线,分析并测试2种制动盘材料在不同冷却速率条件下的微观组织结构及显微硬度。研究结果表明:铸钢制动盘低合金钢的奥氏体转变(A_(C3))温度为847℃,锻钢制动盘低合金钢的A_(C3)温度为862℃,在0.2℃/s的缓慢冷却条件下,锻钢制动盘材料会发生奥氏体向铁素体-珠光体组织的转变,铸钢制动盘材料在冷却速率大于20.0℃/s的条件下可以获得完全的马氏体组织,而锻钢制动盘材料的完全马氏体组织转变临界冷却速率为50.0℃/s。在制动盘实际服役过程中,摩擦面上的局部过热区会在冷却过程中发生贝氏体和马氏体转变并产生局部硬化。In order to clarify the microstructure transformation characteristics of low alloy steels used for cast brake disc and forged brake disc for high-speed trains,the continuous cooling transition behavior was measured by DIL 805L thermal dilatometer.The continuous cooling transformation(CCT)curves were obtained,and the microstructure and microhardness of the low alloy steel used for cast and forged steel brake disc were analyzed at different cooling rates.The results show that the A_(C3)temperature is 847℃for cast brake disc steel,while the A_(C3)temperature is 862℃for the forged brake disc steel.The transition from austenite to ferrite-pearlite was observed at a cooling rate of 0.2℃/s for the forged brake disc steel.For the cast brake disc steel,complete martensite transformation can be observed at the cooling rate of 20.0℃/s,while the critical cooling rate of complete martensite structure transformation of forged brake disc steel is 50.0℃/s.In the actual service process of brake disc,bainite and martensite transformation can occur during cooling in the localized overheated area on friction surface and lead to the increase of hardness.

关 键 词：制动盘 低合金钢 连续冷却转变 CCT曲线 

分 类 号：U271.91[机械工程—车辆工程]