16Mn钢双丝自动埋弧焊接头性能研究

Property investigation of 16Mn steel welded joint by tandem sequence submerged arc welding process

在16Mn钢板上分别进行了单丝和双丝自动埋弧焊工艺试验。在相同的焊接速度条件下,比较了单丝直流、单丝交流和双丝自动埋弧焊熔敷金属的熔敷率,分析了焊接接头金属的显微组织,测试了焊接接头金属的硬度,进行了焊接接头的拉伸试验和冲击试验。结果表明,采用双丝自动埋弧焊工艺熔敷率明显增大,可以提高焊接生产效率,焊缝形状美观。双丝自动埋弧焊与单丝直流、单丝交流自动埋弧焊焊接接头的热影响区、焊缝金属组织基本一致,但由于双丝自动埋弧焊线能量大、加热速度快、高温停留时间长,使其组织较粗大。双丝自动埋弧焊时热影响区未出现成分偏析现象,焊接接头力学性能满足产品技术要求。

The welding tests are conducted on 16Mn steel by using single wire and tandem sequenee submerged arc welding technology.Under the condition of the same welding speed,the deposition efficieney of deposited metal using single wire direct current or ahernating current or tandem sequence submerged arc welding process is compared,the microstructure of welded joint metal is analyzed ,the hardness of welded joint metal is measured ,the tensile test and the impact test of welded joint are performed.The results show that the metal deposition efficiency using tandem sequence submerged arc welding technology is increased obviously ,the welding production efficiency is increased, and the excellent welding bead shape is easily obtained.The HAZ and weld metal microstructure formed using tandem sequence submerged arc welding or single wire direct current or alternating current submerged arc welding technology is constitutionally identical.On the other hand,the higher heat input,faster heating rate,longer high temperature existing time of welding pool when the tandem sequence submerged arc welding technology is used,so the HAZ and weld metal has the resultant coarser microstructure.The Widmanstatten structure in its HAZ and weld metal is resulted.There is no compositional segregation phenomenon in heat-affected zone metal when the tandem sequence submerged arc welding technology is used. The resultant welded joint property can meet to product technical requirement.