摘要
采用扫描电镜,透射电镜,拉伸试验及疲劳试验分析两种6005A铝合金焊接接头的组织及疲劳性能,揭示影响6005A铝合金焊接接头疲劳裂纹形成的主要原因.结果表明,适量铜能显著提升商用6005A铝合金拉伸性能与疲劳性能,其抗拉强度、断后伸长率和高周疲劳强度分别为220 MPa,12%和106 MPa.6005A铝合金焊接区域疲劳失效源于受焊接热输入影响的沉淀相Mg2Si粗化长大,适量铜能稳定热影响区相成分,改善远离焊缝的软化区间强化相Mg2Si在结晶面上偏聚,提高接头区域的疲劳性能.
Microstructure and fatigue properties of welded joints of two 6005 A alloy were investigated by scanning electron microscopy( SEM),transmission electron microscopy( TEM),tensile test and fatigue test. Moreover,the main cause of the fatigue crack initiation of welded joint of 6005 A alloy was revealed. The results show that Cu can clearly improve the tensile and fatigue properties of commercial 6005 A alloy. The tensile strength,elongation,fatigue strength of welded joint of self-made6005A aluminum alloy are 220 MPa,12% and 106 MPa respectively. The size and the distributtion of precipitation phase Mg2 Si in welding heat affected zone affect the fatigue of the 6005 A joint significantly. So,it improves the composition control in welding heat affected zone,the segregated degree on Mg2 Si phase away from weld softening zone and the fatigue properties of welded joint.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2017年第1期95-98,共4页
Transactions of The China Welding Institution
基金
江苏省科技厅自然科学青年基金资助项目(BK20130465)
江苏教育厅高校基金面上资助项目(13KJB430011)
