热矫正对Q345E低合金钢焊接接头组织与性能的影响

Influence of Thermal Correction Welding on Microstructures and Properties of Welded Joints of Q345E Low-alloy Steel

通过拉伸、弯曲、冲击和硬度等试验以及显微组织分析,研究了不同矫正温度对Q345E低合金钢焊接接头组织与性能的影响。结果表明在600-1000℃范围内矫正时,其焊接接头均具有良好的拉伸性能,试件均断于母材,接头抗拉强度随矫正温度增加而下降,但均满足相关标φ要求;焊接接头均具有良好的弯曲性能;矫正温度对焊接接头各区域的冲击性能影响不大,随着试验温度的降低,焊接接头各区域的冲击性能降低。焊接接头各区域硬度值变化不大;矫正温度对焊接接头各个区域的显微组织和晶粒度影响不大。

The microstructures and properties of Q345E low-alloy steel welded joints at different temperature correction were studied by tensile tests, bending tests, impact tests, hardness tests and microstructures analysis. The results show that the welded joint of all Q345 E low-alloy steel have good tensile properties. The specimens are broken in base metal. The tensile strength of the welded joints decreases with increasing temperature correction. All specimens meet the requirements of the relevant standards;all Q345 E low-alloy steel welded joints have good bending performance. The correction temperature has little influence on the impact performance of the welded joints regions, with the test temperature reducing, the impact performance of welded joints regions reduces. All regional hardness in welded joints has little change. The effect of correction temperature on the microstructure of the welded joints and grain size is little.