焊接热循环下V-N正火钢的V(C,N)粒子演变及微观组织分析  

Evolution of V(C,N)particles and microstructure analysis of V-N normalized steel under welding thermal cycle

作　　者：侯洪[1] 蔡焕 王红鸿[2] Hou Hong;Cai Huan;Wang Honghong(Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China;Hubei Province High Performance Steel Materials Collaborative Innovation Center,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]宝山钢铁股份有限公司,上海201900 [2]湖北省高性能钢铁材料协同中心,武汉科技大学,武汉430081

出　　处：《焊接》2020年第2期28-32,I0016,I0017,共7页Welding & Joining

基　　金：国家自然科学基金(51971165)。

摘　　要：采用焊接热模拟方法研究了V-N微合金化正火容器钢在焊接热循环作用下的连续冷却相变;利用光学显微镜、扫描电镜分析了连续冷却相变组织及组成;通过透射电镜分析了V(C,N)析出粒子的形貌及尺寸;采用固溶度积公式计算了VN析出-时间-温度图。得到了模拟焊接热影响区粗晶区连续冷却曲线(SHCCT),给出了不同冷却条件下的室温组织及其组成,得出了V(C,N)的连续冷却过程中的临界析出t 8/5时间约为80 s。并讨论了V,N原子固溶及析出状态对连续冷却相变及微观组织形成的影响。The continuous cooling phase transformation of V-N microalloyed normalized container steel under welding thermal cycling was analyzed by welding thermal simulation method.The continuous cooling transformation microstructure and its composition were analyzed by optical microscope and scanning electron microscopy.The morphology and size of V(C,N)precipitates were analyzed by transmission electron microscopy.VN precipitation-time-temperature curve was calculated by solid solubility product formula.The simulated heat-affected zone continuous cooling transformation(SHCCT)curve was obtained.The microstructure and the phase composition at different cooling conditions were obtained.The critical t 8/5 for V(C,N)precipitation under welding thermal cycle was about 80 s.Effects of solid solution and precipitation state of V and N atoms on continuous cooling phase transformation and microstructure formation were discussed.

关 键 词：V-N微合金化正火容器钢 焊接热循环 V(C N)粒子演变 微观组织 

分 类 号：TG401[金属学及工艺—焊接]