锆管环焊接头残余应力有限元模拟及分析  

Simulation and analysis of finite element of welding residual stress in zirconium pipe

作　　者：郑涵文[1] 赵建平[1] 

机构地区：[1]南京工业大学机械与动力工程学院,江苏南京210009

出　　处：《电焊机》2015年第4期88-96,共9页Electric Welding Machine

基　　金：国家科技支撑计划项目(2011BAK06B03);江苏省六大高峰人才计划项目;大学生创新创业训练计划项目省级重点项目(国家级项目201310291006Z)

摘　　要：应用ABAQUS大型有限元计算软件,建立了锆管单道环焊接头的三维有限元模型,采用热-力顺序耦合、生死单元等技术对锆管焊接的温度场和残余应力场进行了模拟,模拟过程中考虑了相变潜热、材料非线性等因素的影响;研究了不同焊接线能量和不同约束条件对焊接残余应力的影响规律,获得了残余应力分布特征规律。有限元分析显示:焊接等效应力主要存在于焊缝及热影响区,峰值接近锆的屈服强度。环向和轴向应力峰值均达到120 MPa,约为屈服应力的60%。焊件内外壁上,轴向应力对称分布,等效应力大小与线能量大小呈正比,不同约束条件下,等效应力在约束密集方向明显增大。Using the FEA software-ABAQUS,a sequentially coupled welding thermal-stress procedure of zirconium pipe is developed to calculate the weld temperature field and stress distribution field of zirconium pipe. The 3D solid elements of zirconium pipe are built.The factors as convection,latent heat of phase change and material nonlinearity are considered. The effect of different heat inputs and constraint conditions are discussed. The distribution of welding stress of zirconium pipe is obtained. The results show that the mises stress mainly exists in the welds and HAZ and its peak is close to the yield stress of zirconium. The peak of the hoop stress and axial stress all reach 120 MPa,about 60% of the yield stress. The axial stress of the internal and external walls of zirconium pipe form symmetrical distribution. The value of mises stress is proportional to the value of heat input. Under different constraint conditions,the mises stress obviously increases in the direction of intensive constraint.

关 键 词：锆管 ABAQUS软件 生死单元技术 温度场 残余应力场 

分 类 号：TG404[金属学及工艺—焊接]