Study on mechanical properties and microstructure analysis of welded joints of 7A05 aluminum alloy by laser-MIG hybrid welding
7A05 aluminum alloy joints were fabricated by Laser-MIG hybrid welding,of which the tensile strength was tested at room temperature.The tensile fracture surfaces and microstructure were analyzed by SEM and TEM.The fracture surface analysis showed fracture morphologies of small dimple of 2 ~ 5μm on the heat affected zone (HAZ) and big dimple of 30 ~ 50μtm on the weld bead.The fracture is inter-granular fracture with a small amount of cleavage fracture.TEM analysis showed that the HAZ region didnt exists η-phase,but Al3Zr,i.e.,during welding thermal cycle,the joints appeared obvious η-phase back dissolved so that lost η-phase dispersion strengthening effect.O,Na and Fe impurities were detected in the joint,of which the crack originated during tensile testing.Both the impurities and rl-phase back dissolved are responsible for the degrading of the welded joints mechanical properties.
7A05 aluminum alloy laser-MIG hybrid welding mechanical properties microstructure analysis
Hongwei Liu Jinglong Li Zhihua Ma Bing Ma Shengqiang Feng
Shanxi Key Laboratory of Friction Welding Technologies,Northwestern polytechnical University,Xian 7 Shanxi Key Laboratory of Friction Welding Technologies,Northwestern polytechnical University,Xian 7 Ningbo Branch of China Academy of Ordnance Science,Ningbo 315103,China
国际会议
沈阳
英文
1465-1470
2012-09-26（万方平台首次上网日期，不代表论文的发表时间）