超细晶粒钢闪光焊热影响区显微特性分析及其组织有限元模拟  

Microstructure in the HAZ of Ultra-fine Grain Reinforced Steel with Flash Butt Welding

作　　者：王维斌[1] 刘建萍[1] 史耀武[1] 雷永平[1] 田志凌[2] 

机构地区：[1]北京工业大学材料科学与工程学院,北京100022 [2]钢铁研究总院,北京100081

出　　处：《机械工程材料》2004年第8期4-6,28,共4页Materials For Mechanical Engineering

基　　金：国家973‘新一代钢铁材料重大基础研究’资助项目(G1998061500)

摘　　要：结合焊接接头的微观组织观察和宏观性能试验,分析了超细晶粒钢筋直流闪光对焊接头热影响区的显微组织、焊接热影响区各区段的显微硬度分布;利用蒙特卡罗模拟方法,模拟了400MPa超细晶粒钢在一定焊接规范下热影响区奥氏体晶粒的演变情况。结果表明:从熔合区到母材,随着距熔合区距离的增大,显微特性发生明显变化;显微硬度只在焊缝心部区域出现局部降低,但这并不影响整个接头的宏观性能。数值模拟可以预测HAZ中晶粒的分布及温度梯度对晶粒长大的阻碍作用,与实际晶粒大小较为吻合。HAZ's microstructure feature and micro-hardness of 400MPa ultra-fine steel of flash butt welding were investigated by using metallographical examination and test of mechanical properties. Simulated grain growth in HAZ was studied using Monte Carlo method The test results showed that microstructure had an obvious change with distance variety from fusion grain area to parent metal. Flash butt welding joint of reinforced steel bar only resulted in local soften region inside the welded seam but little effect on bulk performance. The simulation results show that this method can predict distribution of grains and effect of steep temperature gradients in HAZ. Comparison of simulated grain size and actual grain size has good consistency.

关 键 词：超细晶粒钢 直流闪光对焊 热影响区 蒙特卡罗模拟 

分 类 号：TG457.11[金属学及工艺—焊接]