逆相变退火对中锰钢组织演变和力学性能的影响
Effect of reverse phase transformation annealing on microstructure evolution and mechanical properties of medium manganese steel
安庆生 1万德成 1马少康 1李杰 1张千禧1
作者信息
- 1. 华北理工大学冶金与能源学院,河北唐山 063210
- 折叠
摘要
对0.22C-3.97Mn-1.57Si-0.1Al-0.043Nb中锰钢进行预淬火处理获得板条状马氏体的初始组织,再进行不同温度的逆相变退火处理.采用扫描电镜(SEM)、X射线衍射仪(XRD)等组织表征手段以及拉伸试验机研究试验钢微观组织演变及力学性能.结果表明,经逆相变退火后室温组织为板条状铁素体、马氏体和残留奥氏体.随退火温度升高,试验钢的抗拉强度逐渐升高,屈服强度逐渐降低,伸长率和强塑积先升高后降低.退火温度为670～690 ℃时,多相组织协调变形,残留奥氏体TRIP效应明显,试验钢表现出优异的力学性能.退火温度为690℃时,试验钢获得最佳力学性能,抗拉强度为1062 MPa,断后伸长率为27.0％,强塑积达到28.7 GPa·％.退火温度高于690℃时,马氏体占比高,残留奥氏体机械稳定性差,试验钢抗拉强度提高但塑性下降;铁素体加工硬化能力增加,残留奥氏体机械稳定性下降,抑制吕德斯带和锯齿流变出现.
Abstract
The initial structure of lath martensite of 0.22C-3.97Mn-l.57Si-0.1Al-0.043Nb medium manganese steel was obtained by pre-quenching,and then reverse phase transformation annealing was performed at different temperatures.The microstructure evolution and mechanical properties of the steel were studied by means of scanning electron microscopy(SEM),X-ray diffractometer(XRD)and tensile test machine.The results show that the microstructure of the experimental steel after reverse phase transformation annealing is ferrite,lath martensite and retained austenite.With the increase of annealing temperature,the tensile strength of the experimental steel gradually increases,the yield strength gradually decreases,the elongation and product of strength and elongation first increases and then decreases.When annealed at 670-690 ℃,the coordinated deformation of the multi-phase structure and the TRIP effect of retained austenite are obvious,and the experimental steel shows excellent mechanical properties.When annealed at 690 ℃,the best mechanical properties can be obtained with the tensile strength of 1062 MPa,the elongation after fracture of 27.0％,and the product of strength and elongation of 28.7 GPa·％.When the annealing temperature is higher than 690 ℃,the hard phase martensite content increases,the mechanical stability of retained austenite is poor,and the tensile strength of the experimental steel increases but the plasticity decreases.The work hardening ability of ferrite increases and the mechanical stability of retained austenite decreases,which inbibite the occurrence of Liiders and sawtooth rheology.
关键词
逆相变退火/残留奥氏体/中锰钢/力学性能Key words
reverse phase transformation annealing/retained austenite/medium manganese steel/mechanical properties引用本文复制引用
基金项目
河北省科技重大专项(21281008Z)
唐山市应用基础研究项目(21130218C)
出版年
2024
NETL
NSTL
万方数据