时效处理对超高强度20Mn2Cr汽车钢组织性能的影响
Effect of aging treatment on microstructure and mechanical properties of ultra-high strength 20Mn2Cr automotive steel
黄文静 1陈健 2裘欣 3丁汉林 4朱国辉 1王子健4
作者信息
- 1. 安徽工业大学冶金工程学院,安徽马鞍山 243002
- 2. 安徽工业大学冶金工程学院,安徽马鞍山 243002;马鞍山钢铁股份有限公司第四钢轧总厂,安徽马鞍山 233241
- 3. 苏州城市学院光学与电子信息学院,江苏苏州 215104
- 4. 苏州大学沙钢钢铁学院,江苏苏州 215006
- 折叠
摘要
研究了时效温度、双级时效处理温度以及碳化物析出对超高强度汽车钢20Mn2Cr冷轧板组织和性能的影响.结果表明,20Mn2Cr钢经过双级时效处理后的硬度远高于单级时效,且在550 ℃+300 ℃条件下双级时效时综合力学性能最佳,其抗拉强度、伸长率、强塑积分别为1 418.1 MPa、10.8％、15.3 GPa·％.SEM观察表明,通过双级时效处理可实现20Mn2Cr钢的多相组织设计与调控,550 ℃+300 ℃双级时效处理后,20Mn2Cr钢的基体组织为粒状贝氏体及少量马氏体,且存在大量细小的Cr碳化物析出.这种多相组织是导致20Mn2Cr钢强度显著提升并获得强塑性良好匹配的主要原因.
Abstract
The effects of aging temperature,double-step aging treatment and the precipitation behavior of carbides on the microstructure and mechanical properties of ultra-high-strength automotive steel 20Mn2Cr were investigated.The results indicate that the hardness of 20Mn2Cr steel after dual-stage aging treatment is significantly higher than that after single-stage aging.For the double-step aged steel,when the first-step aging temperature is set at 550 ℃,the optimum comprehensive mechanical properties with tensile strength of 1 418.1 MPa,elongation of 10.8％,and product of strength and elongation of 15.3 GPa·％can be obtained.SEM observations show that the double-step aging treatment contributes to the design and control of the multi-phase microstructures of 20Mn2Cr steel.The matrix of the steel after 550 and 300 ℃ double-step aging treatment consists of granular bainite and martensite.A large number of fine Cr-rich carbides can also be found in the double-step aging treated steel.The design of multi-phase microstructures is the primary reason for the enhancement of strength and the achievement of excellent match between strength and plasticity of 20Mn2Cr steel.
关键词
20Mn2Cr钢/双级时效/超高强度/碳化物Key words
20Mn2Cr steel/double-step aging/ultra-high strength/carbide引用本文复制引用
出版年
2024
NETL
NSTL
万方数据