单双丝埋弧焊工艺及接头性能比较分析

以生产中常用的16Mn钢材料为焊接母材,采用单丝交流、单丝直流埋弧焊和双丝埋弧焊工艺方法制备焊件.对不同工艺方法得到的焊接接头进行了拉伸试验,焊缝金属和焊接热影响区金属的室温冲击试验,观察了焊缝金属的显微组织,用扫描电子显微镜观察了冲击断口形貌,根据试验数据计算了不同工艺方法下的熔敷速度.比较分析结果表明:双丝埋弧焊工艺下的熔敷速度比单丝交流、单丝直流埋弧焊工艺下的熔敷速度分别提高了108%和64%,焊接速度分别提高了59%和67%,焊接工艺稳定性好,焊缝成形美观.三种工艺方法下得到的焊接接头抗拉强度和屈服强度无明显区别.单丝埋弧焊时焊缝金属的室温冲击韧度值比双丝埋弧焊时的高,单丝交流埋弧焊时焊接热影响区金属的冲击韧度值最高.

Comparing and Analyzing of the Single and the Twin Wire Submerged Arc Welding Procedure and the Welded Joint Property

Weldments of commonly used base metal 16Mn are prepared by single wire submerged arc welding process using alternating/direct current power source and the twin wire submerged arc welding process.For the welded joints obtained by above-mentioned welding processes,the tensile tests of the welded joints are conducted,and the impact tests of the weld and the heat-affected zone(HAZ) of the joint metal are carried out.The microstructure of the weld metal is observed,and the impacted fracture of the weld and the HAZ metal of the joints is recorded by Scanning Electron Microscope(SEM).The deposition rates are calculated based on the experimental data using different welding procedures.The results show that the deposition rate using the twin wire submerged arc welding process has an increase of 108% and 64% respectively,compared with that of the single wire submerged arc welding process using alternating and direct current power source.Correspondingly,the welding travel speed has an increase of 59% and 67% respectively.The stability of the welding technology used is good.The appearance of the weld for all joints is beautiful.But the tensile and the yield strength of the joints obtained by above-mentioned welding processes chosen have little difference.At room temperature,the weld metal impact toughness value of the joint obtained by the single wire submerged arc welding process using alternating/direct current power source is higher than that of the joint obtained by the twin wire submerged arc welding process.The highest is the HAZ metal impact toughness value of the joint prepared by the single wire submerged arc welding process using alternating current power source.