GMAW熔滴喷射过渡形态与保护气体的关系

Relationships between spray transfer forms and shielding gases for GMAW

探讨了GMAW熔滴喷射过渡形态与保护气体间的关系及新突破。结果表明,熔滴喷射过渡形态可以细分为射滴喷射、射流喷射、旋转喷射和脉冲喷射过渡4种类型。GMAW喷射过渡形态的实现取决于3个要素:(1)富氩混合保护气体;(2)电磁力作用方向向下;(3)焊接电流等于或大于转变电流。采用纯Ar保护气体或富Ar混合保护气体时,具备喷射过渡形成三要素,可以实现喷射过渡形态;纯CO_2保护气体时不具备喷射过渡形成三要素,不可能产生喷射过渡形态。开展纯CO_2GMAW喷射过渡形态的探索性研究,有助于发现GMAW新型实用熔滴过渡形态。

The relationships between spray transfer forms and shielding gases for GMAW and its new breakthroughs were discussed.The results show that the spray transfer forms can be subdivided into four types:drop spray,streaming spray,rotating spray and pulse-spray transfer.The realization of spray transfer forms in GMAW depends on three major factors:first,the argon-enriched mixed shielding gas;second,the direction of the electromagnetic force is downward;and third,the welding current is equal to or greater than the transition current.When using pure Ar shielding gas and rich Ar mixed gas,there are three main factors formed by the spray transfer,which can realize the spray transfer form.When the pure CO2 shielding gas is used,there are no three main factors formed by the spray transfer,and it is impossible to generate spray transfer form.The exploratory study of the GMAW spray transfer form with pure CO2 shielding gas will help to discover the new practical droplet transfer form in GMAW.