几何和材料拘束与高匹配焊接接头断裂韧性的统一关联

Unified Correlation of Geometry and Material Constraints with Fracture Toughness of Welded Joint with High Mismatch

采用数值计算方法研究了拘束参数A_p对高匹配窄间隙焊接接头面内/面外几何拘束和材料拘束的统一表征能力,以及参数A_p与接头不同位置裂纹断裂韧性的可关联性。结果表明,几何和材料拘束对高匹配窄间隙焊接接头的J-R阻力曲线和断裂韧性J_C具有显著的影响。参数A_p可以统一地表征该种接头不同位置裂纹的面内/面外几何拘束及由材料强度失配引起的材料拘束,基于A_p可建立统一拘束与接头断裂韧性的关联。计算得到了不同位置裂纹的标称断裂韧性J_C/Jref与A_p的关联式。

The capability of the constraint parameter Ae for characterizing in-plane, out-of-plane and mate- rial constraints in welded joints with high mismatch and narrow gap has been investigated by numerical calculations,and the unified correlation of the Ap with fracture toughness of the welded joints was also studied. The results show that the geometry and material constraints have significant effects on the J-R curve and fracture toughness Jc of the welded joints with high mismatch and narrow gap. The parameter Ap can uniformly characterize in-plane and out-of-plane constraints and material constraint caused by strength mismatches for the cracks with different positions in the welded joints. Based on the constraint parameter Ap, the unified correlation of constraints with fracture toughness of the welded joint can be established. The correlation formulas of the normalized fracture ess Jc/Jref with √Ap have been obtained by calculations.