预熔氧化层对AA-TIG焊缝形貌的影响

Effect of premelting oxide layer on AA-TIG weld shape

AA-TIG焊(arc assisted activating TIG welding)是一种新型高效焊接方法,该方法通过焊前采用小电流辅助电弧以Ar+O2作为保护气体在待焊部位预熔一道氧化层,然后再进行常规TIG焊,可获得深而窄的焊缝.试验通过改变辅助电弧工艺参数来改变预熔氧化层的厚度,分析预熔氧化层厚度对焊缝成形的影响.结果表明,辅助电弧的电流、速度以及辅助电弧中氧气流量对预熔氧化层厚度有很大的影响,辅助电弧中氧气流量越大、辅助电弧热输入越大时,预熔氧化层越厚;AA-TIG焊时预熔氧化层的厚度对焊缝深宽比影响较大,随着预熔氧化层的增厚,焊缝深宽比先增加后减小.

AA-TIG welding is a new and efficient welding process before which pre-melting oxide layer was prepared on weld position by low current assisting arc with Ar+O2 as shield gas.As a result,a deep and narrow weld bead can be obtained.In this experiment,through turning the assisting arc parameters to change the thickness of oxide layer,the influence of the thick of oxide layer on stainless steel weld formation was analyzed.The results show that the parameters of assisting arc have great effect on the thickness of oxide layer,the oxide layer becomes thicker when the oxygen gas flow rate or the heat input of assisting arc increase.And the thickness of oxide layer influences the weld depth/width ratio,the weld depth/width ratio climbs up at first and then declines with the increase of the thickness of oxide layer.