50CrVA弹簧钢的连续冷却转变行为研究  

Research on continuous cooling transformation behavior of 50CrVA spring steel

作　　者：赵阳 江飞 孙艳姣 ZHAO Yang;JIANG Fei;SUN Yanjiao(School of Materials Science and Engineering,Northeastern University,Shenyang 110819,Liaoning,China;Zenith Steel Group(Nantong)Co.,Ltd.,Nantong 226100,Jiangsu,China;Liaoning Province Important Technology Innovation and Research and Development Base Construction Engineering Center,Shenyang 110168,Liaoning,China)

机构地区：[1]东北大学材料科学与工程学院,辽宁沈阳110819 [2]中天钢铁集团(南通)有限公司,江苏南通226100 [3]辽宁省重要技术创新与研发基地建设工程中心,辽宁沈阳110168

出　　处：《四川冶金》2022年第5期5-7,35,共4页Sichuan Metallurgy

基　　金：中央高校基本科研业务费(N2002024)。

摘　　要：50CrVA钢是一种常用的弹簧钢,研究其连续冷却转变行为对于制定轧后冷却工艺和热处理工艺至关重要。本文采用热膨胀法和显微组织观察相结合的方法研究了50CrVA弹簧钢的连续冷却转变行为,并绘制了静态连续冷却转变曲线。结果表明:当冷却速率为0.05~1.00℃/s时,50CrVA钢的转变组织为珠光体和铁素体,在此冷却速率范围内随着冷却速率的增加,珠光体含量增加而铁素体含量降低;当冷却速率为2~10℃/s时,转变组织为贝氏体和马氏体;当冷却速率为20℃/s时,转变组织为马氏体。随着冷却速率的增加,50CrVA弹簧钢的硬度随之增加,该钢的马氏体临界冷却速率为20℃/s。50CrVA steel is a commonly used spring steel,and it is essential to study its continuous cooling transformation behavior for formulating the cooling process after hot rolling and the heat treatment process.In this paper,the continuous cooling transformation behavior of 50CrVA spring steel was investigated by combination of thermal expansion method and microstructure observation,and the static continuous cooling transformation curve was drawn.The results show that when the cooling rate is 0.05~1.00℃/s,the microstructure is pearlite and ferrite.In this cooling rate range,as the cooling rate increases,the volume fraction of pearlite increases and the volume fraction of ferrite decreases.When the cooling rate is 2~10℃/s,the transformation microstructure is bainite and martensite.When the cooling rate is up to 20℃/s,the microstructure is martensite.With the increase in cooling rate,the hardness of 50CrVA spring steel increases,and the critical cooling rate of martensite transformation is 20℃/s.

关 键 词：50CrVA钢 连续冷却转变 热膨胀法 马氏体 硬度 

分 类 号：TG142.12[一般工业技术—材料科学与工程]