摘要
以4mm 2219-T87高强铝合金平板为对象,分别使用ER2319 Al-Cu焊丝和ER5087 Al-Mg焊丝作为填充材料,研究双脉冲变极性钨极氩弧焊(VP-GTAW)对接接头的显微组织和力学性能。结果表明,与常规VP-GTAW工艺相比,对焊接电流进行低频脉冲调制的双脉冲VP-GTAW工艺可细化晶粒,改善焊缝显微组织;提高对接接头力学性能,且抗拉强度和断后伸长率均在低频脉冲频率为2Hz时达到最大值。与Al-Cu焊丝接头相比,Al-Mg焊丝接头可以在保持对接接头塑性的同时,提高抗拉强度和显微硬度,抗拉强度最大为328MPa,达到母材的72%;焊缝区显微硬度达到100HV以上。Al-Cu焊丝接头和Al-Mg焊丝接头均为脆性-韧性混合断裂。
The butt welding experiments were carried out using double-pulsed variable polarity gas tungsten arc welding （VP-GTAW） process with 4mm 2219-T87 high strength aluminum alloy as base metal, and ER2319 Al-Cu wire and ER5087 Al-Mg wire as filler wire, respectively. The microstructure and mechanical properties of welded joints were investigated. The results show that double-pulsed VP-GTAW process has benefits on refining grain size and improving mechanical properties. The maximum tensile strength and elongation can be achieved when the frequency of low-frequency pulse frequency is 2Hz. The tensile strength and microhardness of the 2219 aluminum alloy welded joints using Al-Mg wire are superior to that using Al-Cu wire with similar plastic property. The maximum tensile strength is 328MPa, which is 72% of base metal. The microhardness of weld zone is above 100HV. Fracture pattern of all welded joints is mixed fracture of brittle and ductile.
作者
从保强
樊弢
齐铂金
王义朋
祁泽武
CONG Baoqiang;FAN Tao;QI Bojin;WANG Yipeng;QI Zewu(School of Mechanical Engineering and Automation,Beihang University,Beijing 100191,China;MIIT Key Laboratory of Aeronautics Intelligent Manufacturing,Beijing 100191,China)
出处
《航空制造技术》
2018年第20期16-21,共6页
Aeronautical Manufacturing Technology
基金
北京市自然科学基金项目(3182020)
