国内外典型药芯焊丝的熔滴过渡及其工艺特性

Metal transfer and technological characteristic of typical titanium flux-cored wires at home and abroad

采用高速摄影、平板堆焊以及化学分析等试验方法,测试、对比研究了国内外3种典型钛型渣系药芯焊丝的熔滴过渡及其工艺特性。结果表明,基于3种焊丝熔滴过渡特性与工艺性之间的关系,提出改善熔滴过渡特性新观点,即控制熔滴尺寸是必要条件,而控制“熔滴大角度过渡次数”、“熔滴存在时间和过渡间隔均匀性”、“熔滴依附渣柱过渡次数”等指数是充分条件,二者缺一不可。药芯焊丝的非轴向排斥滴状过渡形态、渣柱直接进入熔池,以及电弧区焊丝接口纵向张开现象,可能导致焊接冶金反应不完全和冶金过程新变化。熔滴过渡区的渗Si反应使熔滴氧化增氧,熔滴被细化,有利于改善熔滴过渡特性。3种典型药芯焊丝的熔滴过渡形态和电弧形态接近,然而过渡指数不尽相同,表现为B焊丝有3项工艺性指标领先,其机理在于控制熔滴过渡和电弧形态的“充分”、“必要”条件均占优势。

The metal transfer and technological characteristic of three typical titanium flux-cored wires at home and abroad were researched by experimental methods such as high-speed camera, bead-on-plate weld as well as chemical analysis and compared with one another, so a new-concept on improving metal transfer was proposed based on the relationship between metal transfer and technological characteristics. The result shows that controlling the droplet dimension is the necessary condition, and controlling such parameters as ' the number of large angle metal transfer' ,' the time of being droplet and the uniformity of metal transfer' and ' the number of slag pole-guided metal transfer' are the sufficient conditions, and neither is dispensable. The mode of non-axial repelled droplet transfer, the phenomena of slag pole directly inserting into the weld pool as well as the phenomena of opening vertically of the wire may cause welding metallurgy reaction incomplete. The droplet was oxidized by the silicon transferring reaction which adds more oxygen into the droplet, and the droplet was refined which the property of metal transfer was improved. The three typical flux-cored wires possess similar metal transfer characteristics and arc forms, but the parameters of metal transfer vary widely. The wire B is better than others in three parameters, because its necessary condition and the sufficient condition of controlling of metal transfer as well as arc form are better than other wires.