强度匹配对焊接钢管断裂韧性影响的有限元分析

为了研究焊接过程中强度匹配对焊接接头断裂韧性的影响，以弹塑性断裂力学理论为基础，基于细观塑性损伤模型，应用ABAQUS软件对大范围屈服条件下的全周向内裂纹管采用轴对称模型及基于小范围屈服的修正边界层模型（MBL）分别进行有限元模拟分析计算。研究结果表明:高配且匹配系数越高，焊接接头的断裂韧性及阻力曲线越高；随匹配系数增加，失配约束M减小，管子的断裂韧性增大；不同强度匹配引起的失配约束差异随裂纹扩展而增大。

Finite Element Analysis of the Effect of Strength Match on Ductile Fracture Welded Pipe

In order to study the influence of strength match on welded joint ductile fracture in welding process, based on elastic-plastic fracture theory and microscomic plastic damage model, it respectively carried out finite element simulation analysis and calculation for two kinds of model by using ABAQUS software, one is axisymmetric model for circumferential direction internal crack pipe under wide scale yield condition, the other is modified boundary layer (MBL) model based on small scale yield. The result indicated that the higher matching coefficient is, the higher the fracture toughness of welded joint and resistance curve; with matching coefficient increasing, the mismatch constraint M decreased, and the ductile toughness increased;the difference of mismatch constraint caused by different strength matching increased with the crack growth.