65MnCr耐磨钢的连续冷却曲线和相变规律  

Continuous cooling curve and phase transformation behavior of wear resistant steel 65MnCr

作　　者：陈涛[1] 赵爱民[2] 樊红亮[2] 李晓刚[2] 姚舜[2] 

机构地区：[1]河北工业职业技术学院,河北石家庄050091 [2]北京科技大学冶金工程研究院,北京100083

出　　处：《材料热处理学报》2016年第9期144-150,共7页Transactions of Materials and Heat Treatment

基　　金：河北工业职业技术学院应用研发中心项目(2015YF01);河北省科技计划项目(15211031)

摘　　要：利用DIL805A热膨胀仪结合金相—硬度法,测得了低合金耐磨钢65Mn Cr的临界点温度Ac1,Ac3以及Ms;并绘制了该材料的过冷奥氏体连续冷却转变曲线（CCT曲线）;研究了65Mn Cr过冷奥氏体连续冷却过程中组织转变规律;最后对65Mn Cr和65Mn的CCT曲线做了比较。结果表明：相比65Mn,65Mn Cr钢CCT曲线大大右移,淬透性大大增加;该钢的临界冷却速度为1~3℃/s;得到淬火最佳参数：淬火速度为3℃/s,堆冷温度为200~400℃。The critical temperatures,such as Ac1,Ac3 and Msof a 65 Mn Cr steel were determined by means of dilatometry on a DIL805 A dilatometer combined with microstructure observation and hardness measurement.The continuous cooling transformation（CCT） curves of under-cooled austenite of the 65 Mn Cr steel were obtained.The continuous cooling phase transformation behaviour of under-cooled austenite was studied,and the CCT curves of the 65 Mn Cr steel and 65 Mn steel were compared.The results show that the CCT curve of the 65 Mn Cr steel is greatly shifted to the right,and its hardenability is significantly increased compared with that of the 65 Mn steel.The critical cooling rate of the 65 Mn Cr steel is recommended in the range of 1 ℃ /s to 3 ℃ /s.The optimum quenching parameters for the steel are obtained：The critical quenching rate is 3 ℃ /s,and the stack cooling temperature is in the range of 200-400 ℃.

关 键 词：淬透性 连续冷却曲线 相变 热膨胀 低合金耐磨钢 

分 类 号：TG135.6[一般工业技术—材料科学与工程] TG142.72[金属学及工艺—合金]