微合金钢回温变形时的组织转变和铁素体动态再结晶行为

发布时间：2018-05-03 13:56

  本文选题：微合金钢 + 回温轧制　； 参考：《材料工程》2015年11期

【摘要】：采用GLEEBLE 3800热模拟机进行回温变形热压缩实验,研究回温温度对微合金钢组织转变和铁素体动态再结晶行为的影响。利用金相显微镜、扫描电镜、透射电镜和背散射电子衍射观察实验钢的微观组织和晶粒取向,并对形变时的应力-应变曲线进行分析。结果表明:实验钢回温变形可获得超细晶组织,晶粒平均等效直径约2μm;在回温过程中变形发生动态回复形成亚晶组织,峰值温度变形发生铁素体动态再结晶形成超细晶粒;动态再结晶机制包括晶界迁移和亚晶的转动生长,回温到700℃和750℃时以前者为主,再结晶不充分,保留了条带状变形铁素体,800℃变形时,两者共同作用,形成均匀的等轴状超细晶组织;通过线性回归计算得到实验钢峰值温度变形时铁素体动态再结晶激活能Qd=250.18kJ/mol。
[Abstract]:The effect of temperature on microstructure transformation and dynamic recrystallization behavior of ferrite in microalloyed steel was studied by using GLEEBLE 3800 thermal simulator. The microstructure and grain orientation of the experimental steel were observed by metallographic microscope, scanning electron microscope, transmission electron microscope and backscatter electron diffraction, and the stress-strain curves during deformation were analyzed. The results show that the ultrafine grain structure can be obtained by reheating deformation of experimental steel, the average equivalent diameter of grain is about 2 渭 m, and the subcrystalline structure is formed by dynamic recovery during deformation and dynamic recrystallization of ferrite to form ultrafine grain during peak temperature deformation. The mechanism of dynamic recrystallization includes grain boundary migration and subcrystal rotation growth. The former is dominant at 700 鈩，

本文编号：1838747