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 pulsespray 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 CO,2, 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 CO,2, shielding gas will help to discover the new practical droplet transfer form in GMAW.
关键词
喷射过渡熔化极气体保护焊富氩混合气体转变电流
Keywords
spray transfergas metal arc welding(GMAW)rich-argon mixing gastransition current