摘要缆式焊丝气保焊是最近几年来出现的一种创新型焊接方法它具有高效、节能且优 质的特点，其设备简单、易实现焊接自动化，尤其适合船舶厚板焊接。它主要克服了 传统单丝气保焊焊丝直径小、焊接参数小及焊接飞溅大等缺点。目前，针对缆式焊丝 气保焊的研究还处于初级阶段，主要集中在焊接温度场、应力场和高效节能方面。试 验研究表明在相同焊接条件下，缆式焊丝气保焊与埋弧焊热效率相近，缆式焊丝气保 焊 焊 件 表 面 热 影 响 区 较 埋 弧 焊 窄 ， 缆 式 焊 丝 气 保 焊 与 埋 弧 焊 应 力 场 相 似 。 本文采用理论结合实际的试验方法，采用Φ3。6mm 药芯缆式焊丝和Φ1。2mm 药芯 焊丝配合 20%Ar+80%CO2 混合气，使用平特性焊接电源配合等速送丝方式进行平板 堆焊；通过电信号采集系统采集缆式焊丝气保焊不同电弧形态下的电压电流波形；利 用高速摄像拍摄不同的电弧形态，对比了不同熔滴过渡方式下的电弧形态，同时总结了影响缆式焊丝气保焊电弧形态的焊接参数；最后分析不同电弧形态下的焊缝形貌， 并对焊缝接头做了宏观金相分析；为进一步推广缆式焊丝气保焊的应用奠定理论基础。80924

试验结果表明：缆式焊丝气保焊有 3 种熔滴过渡方式，即旋转排斥过渡、颗粒过渡和射滴过渡；缆式焊丝气保焊有 4 种电弧形态，分别是斜柱体、圆台状、钟罩状和 束状；缆式焊丝气保焊焊接时焊丝端部及熔滴是不停地旋转，熔滴以一定的旋转速度 进入熔池，从而加快熔池的搅拌作用；缆式焊丝气保焊电弧的阳极区是多极区耦合而 成的；缆式焊丝气保焊使用较大焊接电流时，电磁收缩力强，电弧形态呈束状，散热 面积小，热量损失相对少；旋转排斥过渡时电弧形态为斜柱体状和圆台状，颗粒过渡 时的电弧形态为钟罩状，射滴过渡时电弧形态为束状；焊接电流对电弧形态影响最大， 其次为电弧电压，焊丝干伸长和焊接速度影响最弱；缆式焊丝气保焊电弧形态为斜柱 体时，焊缝成形差，焊缝表面有气孔和凹痕等缺陷，焊接飞溅大，熔深浅且余高过大； 电弧形态为钟罩状时，焊缝成形明显得到改善，焊缝表面光滑无明显气孔等缺陷，熔 深变大，余高减小；电弧形态为束状时，焊缝成形最佳，熔深明显变大。

毕业论文关键词：缆式焊丝气保焊；电弧形态；焊缝成形

Abstract Cable-type welding wire (CWW) gas metal arc welding (GMAW) is a high efficient, energy-saving and high quality innovative welding method in recent years。 The equipment of CWW GMAW is simple and easy to realize welding automation, and it is especially suitable for the welding of hull thick plate。 This new method mainly overcomes the shortcomings of traditional single wire GMAW with small wire diameter, small welding parameters and large welding splash。 At present, the research of CWW GMAW is still in the primary stage, which is mainly focus on the welding temperature field, welding stress field, high efficiency and energy saving。 Experimental research shows that under the same welding condition, CWW GMAW has the similar heat efficiency of submerged arc welding; the heat affected zone of CWW GMAW is narrow compared with submerged arc welding; CWW GMAW and submerged arc welding have similar stress field。

In this paper, we use the method of theory analysis combining with experiment, adopting Φ3。6mm cored CWW and 20%Ar+80%CO2 mixed gas, using the  constant voltage welding power source and constant wire feeding to conduct plate welding。 The voltage and current waveforms of different arc shape were acquired through the electrical signal acquisition system; the different arc shape and droplet transfer mode were shot by the high-speed camera。 In addition, we conducted the force analysis and heat production theory of CWW GMAW coupling arc, comparing the arc shape of different droplet transfer mode and summarizing the effects of welding parameters on CWW GAMW arc shape。 Finally, we analyzed the weld appearance of different arc shape, and conducted metallographic analysis of weld joint, laying the theoretical foundation for the further application of CWW GMAW。