摘要
结合试验分析与热力学计算,采用扫描电镜(SEM)、透射电镜(TEM)和X射线衍射(XRD)等方法研究了两相区退火对复合添加Al-V-Ti的TRIP钢组织和力学性能的影响。研究发现,试验钢在820℃两相区退火3 min、400℃贝氏体区等温5 min时获得最佳力学性能,即抗拉强度为1 093 MPa,断后伸长率为23. 9%,强塑积可达26 123 MPa·%。此时试验钢中残留奥氏体以薄膜状分布于贝氏体与铁素体间,残留奥氏体体积分数为19. 61%,其含碳量为1. 41%,残留奥氏体稳定性参数R值最高为27. 7,并与强塑积呈正比关系。此外,随着两相区退火时间的延长,试验钢的屈服强度降低、屈服平台长度缩短,当退火时间超过5 min后,试验钢开始呈现出连续屈服的特性。
Combined with experimental analysis and thermodynamic calculation,the effect of intercritical annealing(IA)on microstructure and mechanical properties of Al-V-Ti added TRIP steel was studied by scanning electron microscope(SEM),transmission electron microscopy(TEM)and X-ray diffraction(XRD)techniques.The results showed that the best mechanical properties,e.g.,tensile strength of 1 093 MPa,elongation of 23.9%,strength and ductility product of 26 123 GPa·%,could be obtained after IA at 820℃for 3 min and isothermal treatment in bainite region at 400℃for 5 min.Accordingly,the retained austenite in the form of films was distributed between the ferrite and bainite,the maximum volume fraction of retained austenite was 19.61%,and its carbon content was 1.41%,the highest R value of residual austenite stability parameter was 27.7,which was directly proportional to the strength and ductility product.With the extension of IA time,the yield stress decreased and the length of yield platform continuously shortened.When the annealing time exceeded 5 min,the test steel began to exhibit continuous yielding characteristics.
作者
陈立本
姜沪
张功庭
何燕霖
李麟
Chen Liben;Jiang Hu;Zhang Gongting;He Yanlin;Li Lin(School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China;Pangang Group Research Institute Co.,Ltd.,Panzhihua Sichuan 617000,China)
出处
《上海金属》
CAS
北大核心
2018年第5期84-89,共6页
Shanghai Metals
关键词
TRIP钢
两相区退火
残留奥氏体
力学性能
TRIP steel
intercritical annealing
retained austenite
mechanical property
