补焊道次对Q345B低合金钢焊接接头疲劳性能的影响

摘要

通过脉动拉伸试验研究了补焊道次对Q345B低合金钢焊接接头疲劳性能的影响。结果表明：与未补焊的接头相比，一次补焊后焊接接头的中值疲劳强度值略有下降（差4．6MPa）；二次补焊和一次补焊的中值疲劳强度基本相当，仅差0．7MPa疲劳裂纹启裂区和扩展区具有典型的疲劳断裂特征，终断区形貌为准解理和少量浅韧窝。%The effect of repairing welding passes on the fatigue property of Q345B low-alloy steel by pulsating fatigue test. The results show that the fatigue strength of once-repairing welding decreased slightly (only for 4. 6 MPa) comparing with that of non-repairing welding, and the fatigue strength of second-repairing welding basically match to that of once-repairing welding, the difference between them was only 0. 7 MPa. The eraekinitiation and propagation area of fatigue crack had the typical fatigue fracture characteristics, fatigue end broken area morphology was quasi-cleavage and little dimple.