CO_2+Ar非熔化极双层气保护焊中CO_2影响的研究

Influence of CO_2 in no melted double-layer gas CO_2+Ar shielded arc welding

采用自主设计的双层焊枪,内层通少量Ar,外层通CO_2,实现了CO_2+Ar非熔化极双层气保护焊。在相同焊接参数下,对比CO_2+Ar非熔化极双层气保护焊和传统TIG焊的焊接试验,并进一步结合数值模拟获得电弧温度、气体质量分数分布以及工件表面的热流密度等信息,探究CO_2对电弧电压、形态和焊缝成形的影响。结果表明,与传统纯氩弧相比,外层CO_2的引入对电弧有压缩作用,电弧电压提高了约4.5 V,工件表面的最大热流密度提高了26%,相同焊接参数下,熔深可达传统TIG焊的3.6倍。

No melted double layer gas of CO2+Ar shielded arc welding,a small amount of Ar inside and CO2 outside,was realized by self designed double layer welding torch.In this paper,influence of CO2 on arc shape and appearance of weld were discussed by welding test of no melted double-layer gas CO2+Ar shielded arc welding and conventional TIG welding under the same welding parameters and obtaining information of arc temperature,distribution of gas mass fraction and heat flux information on the workpiece surface with the help of numerical simulation.The results showed that the introduction of the outer layer of CO2 had a compressive effect on the arc compared to the conventional pure argon arc,the arc voltage increased by about 4.5 V,the maximum heat flux on the workpiece surface increased by 26%,and the penetration reached 3.6 times that of the traditional TIG welding.