Xiao Ning, Kong Haoyu, Sun Qingjie, Ma Ninshu
METALLECO Inc., No. 3185 Dundas St. W, 2F, Oakville, ON L6M 4J4, Canada.
Joining and Welding Research Institute, Osaka University, Osaka 567-0047, Japan.
Materials (Basel). 2024 Dec 18;17(24):6183. doi: 10.3390/ma17246183.
Narrow-gap arc welding is an efficient method that significantly enhances industrial production efficiency and reduces costs. This study investigates the application of low-alloy steel wire EG70-G in narrow-gap gas metal arc welding (GMAW) on thick plates. Experimental observations were made to examine the arc behavior, droplet transition behavior, and weld formation characteristics of double-wire welding under various process parameters. Additionally, the temperature field of the welding process was simulated using finite element software (ABAQUS 2020). Finally, the microstructure and microhardness of the fusion zone in a double-wire, single-pass filled joint under the different welding speeds were compared and analyzed. The results demonstrate that the use of double-wire GMAW in narrow-gap welding yielded positive outcomes. Optimal settings for wire feeding speed, welding speed, and double-wire lateral spacing significantly enhanced welding quality, effectively preventing side wall non-fusion and poor weld profiles in the welded joints. The microstructure of the fusion zone produced at a higher welding speed (11 mm/s) was finer, resulting in increased microhardness compared to welds obtained at a lower speed (8 mm/s). This is attributed to the shorter duration of the liquid molten pool and the faster cooling rate associated with higher welding speed. This research provides a reference for the practical application of double-wire narrow-gap gas metal arc welding technology.
窄间隙弧焊是一种能显著提高工业生产效率并降低成本的高效方法。本研究探讨了低合金钢焊丝EG70-G在厚板窄间隙气体保护金属极电弧焊（GMAW）中的应用。通过实验观察，研究了不同工艺参数下双丝焊接的电弧行为、熔滴过渡行为和焊缝成形特征。此外，利用有限元软件（ABAQUS 2020）对焊接过程的温度场进行了模拟。最后，对不同焊接速度下双丝单道填充接头熔合区的微观组织和显微硬度进行了比较和分析。结果表明，在窄间隙焊接中采用双丝GMAW取得了良好效果。送丝速度、焊接速度和双丝横向间距的优化设置显著提高了焊接质量，有效防止了焊接接头的侧壁未熔合和焊缝成形不良。较高焊接速度（11mm/s）下产生的熔合区微观组织更细，与较低速度（8mm/s）下获得的焊缝相比，显微硬度有所提高。这归因于较高焊接速度下液态熔池持续时间较短和冷却速度较快。本研究为双丝窄间隙气体保护金属极电弧焊技术的实际应用提供了参考。
