纵向磁场对WQ960钢焊接接头组织和性能的影响

为了研究纵向磁场对焊接接头的显微组织、冲击韧性和抗拉强度的影响,利用纵向磁场辅助MAG焊焊接WQ960高强钢.纵向磁场的施加提高了焊接接头的抗拉强度、冲击吸收功和冲击韧性,改善了焊接接头的显微组织,且焊接接头的显微组织主要由细小的针状铁素体构成.结果表明,当励磁电流达到2.5 A且磁场频率为20 Hz时,焊接接头的抗拉强度和低温冲击功均可达到最大值,分别为839 MPa和72 J,且分别提高了17.01%和24.14%;先共析铁素体和侧板条铁素体数量相应减少,因而形成了更多的针状铁素体.

Effect of longitudinal magnetic field on microstructure and properties of WQ960 steel welded joint

In order to study the effect of longitudinal magnetic field on the microstructure, impact toughness and ultimate tensile strength of welded joint, the longitudinal magnetic field was used to assist the MAG welding of WQ960 high strength steel. Through imposing the longitudinal magnetic field, the ultimate tensile strength, impact absorbing energy and impact toughness of welded joint are enhanced, the microstructure of welded joint gets improved, and the microstructure is mainly composed of fine acicular ferrite. The results show that when the exciting current reaches 2.5 A and the field frequency is 20 Hz, both ultimate tensile strength and low temperature impact energy of welded joint can reach the maximum value. And the corresponding values are 839 MPa and 72 J, which increase by 17.01% and 24.14%, respectively. The quantity of proeutectoid ferrite and side plate ferrite relatively reduces, while more acicular ferrite forms.