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4.6 MPa); 二次补焊和一次补焊的中值疲劳强度基本相当, 仅差0.7 MPa; 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 crackinitiation and propagation area of fatigue crack had the typical fatigue fracture characteristics, fatigue end broken area morphology was quasi-cleavage and little dimple.