Q345R和S30408异种钢焊接接头组织与性能分析

Analysis about the microstructure and properties of the welded joint of dissimilar steels between Q345R and S30408

异种钢焊接在各工程领域中应用广泛,但由于异种钢在冶金相容性、物理和化学性能方面差异较大,接头组织不均匀,力学性能较差,因此有必要研究其组织及性能。选用A302焊条,采用焊条电弧焊(SMAW)对Q345R和S30408异种钢进行焊接,并进行焊后热处理,利用微观金相组织观察,冲击、弯曲及拉伸等力学测试分析焊接接头的组织和力学性能。实验结果表明:Q345R和S30408异种钢焊接接头具有优良的力学性能,抗拉强度达到569 MPa以上,-20℃低温平均冲击功达到48 J以上,材料最佳热处理温度为550℃。

Dissimilar steel welding is widely used in various engineering fields. However,due to the differences in metallurgical compatibility,physical and chemical properties,the microstructure of the dissimilar steel joint is easy to be uneven,and the mechanical properties are poor. It is necessary to carry out research on its organization and performance. In this paper, welding of Q345R and S30408 dissimilar steels was carried out by using A302 electrode. The microstructure was observed,impact,bending and tensile tests were carried out. The microstructure of welded joints was investigated by means of mechanical welding. And mechanical properties were analyzed. The experimental resuhs show that the welding joint with excellent mechanical properties,of which tensile strength is above 569 MPa,the average value of impact energy at the temperature below 20 ℃ is above 48 J, the best heat treatment temperature is 550 ℃.