复合脉冲方波电流频率对5A06铝合金焊缝组织和性能的影响  

Effect of hybrid-pulse square-wave current frequency on microstructure and mechanical properties of 5A06 aluminum alloy welds

作　　者：从保强[1] 齐铂金[1] 周兴国[1] 罗军[1] 

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100191

出　　处：《焊接学报》2010年第1期89-92,共4页Transactions of The China Welding Institution

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复合高频脉冲方波变极性电弧焊接技术,以5A06铝合金为试验对象,采用复合脉冲变极性TIG电弧焊接工艺,研究了复合脉冲方波电流频率对焊缝显微组织和力学性能的影响.结果表明,与未加入高频脉冲方波电流作用相比,当复合脉冲电流频率不超过20 kHz时,5A06铝合金焊接接头的显微组织和性能出现一定程度的降低,脉冲电流频率为40 kHz时,焊缝中心区组织细化,接头软化程度降低,接头力学性能明显改善,抗拉强度和断后伸长率分别达到母材金属的95.8%和84.8%.A novel ultrafast-convert hybrid-pulse square-wave variable polarity arc welding technology for aluminum alloy is developed.Based on the hybrid-pulse variable polarity TIG welding technique,the effect of hybrid-pulse square-wave current frequency on the microstructure and mechanical properties of 5A06 welds is researched.The experimental results show that,compared with no hybrid-pulse current,the weld mechanical properties are decreased when the pulse current frequency is less than 20 kHz.Under the condition of pulse current frequency up to 40 kHz,the size of crystal grains and degree of welds softening are decreased,tensile strength of weld joints is improved obviously.The rates of weld tensile strength and percentage elongation to base metal are 95.8% and 84.8%,respectively.

关 键 词：超快变换 复合高频脉冲 脉冲频率 变极性 铝合金 

分 类 号：TG457.14[金属学及工艺—焊接]