摘要
研究开发了一种适用于铝合金材料的新型超快速变换变极性方波电弧焊接技术,以2219-T87高强铝合金为试验对象,分别采用常规变极性和超快变换变极性TIG电弧焊接工艺,研究了变极性电流的换向速率对焊缝气孔敏感性和接头力学性能的影响.结果表明,提高变极性电流上升沿和下降沿的变化速率,减少电流过零时间,可显著降低2219-T87高强铝合金焊接接头的气孔敏感性,焊缝中气孔数量明显减少甚至消除;由于焊缝熔合区的软化问题,焊接接头抗拉强度和断后伸长率的增加幅度不大,分别提高了8.97%和12.6%.
A novel arc welding technique with ultrafast-convert variable polarity square-waveform for aluminum alloys was developed. The influence of variable polarity current converting speed on the porosity and mechanical properties of 2219-T87 weld was studied based on the conventional and ultrafast-convert variable polarity tungsten inert gas (VPTIG) welding techniques, respectively. The experimental results show that compared with the conventional variable polarity welding, weld porosity is obviously improved in the case of the faster current converting speed and less zero-crossing time. The number of gas pore is reduced and eliminated indeed. The tensile strength and percentage elongation of the weld joints are respectively enhanced by 8.97% and 12.6% due to the softening of weld bond area.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2010年第8期21-24,共4页
Transactions of The China Welding Institution
关键词
高强铝合金
超快变换
变极性
焊缝气孔
high strength aluminum alloy
ultrafast convert
variable polarity
weld porosity
