中文摘要：

对8 mm厚AZ31镁合金及其TIG焊横向十字接头疲劳性能进行了试验和分析。结果表明,在2×106的循环次数下,AZ31镁合金母材的疲劳强度为36.0 MPa;TIG焊横向十字接头的疲劳强度为17.2 MPa,为母材疲劳强度的47.8%;镁合金焊接接头的疲劳特征曲线低于国际焊接学会(IIW)针对铝合金推荐的FAT28标准。所以,在镁合金焊接结构的疲劳设计中必须采取更小的疲劳设计级别。

英文摘要：

The low fatigue behavior of Mg alloy is one of factors of restricting use of Mg alloy.The fatigue behavior of AZ31 Mg alloy in 8 mm and its transverse cross joint by TIG welding was studied.The results show that the fatigue strength of base metal and welded joint are dissatisfactory,under 2×106 cycles,the fatigue strength of base metal is 36.0 MPa,and the fatigue strength of transverse cross joint is 17.2 MPa,which is 47.8% of fatigue strength of base metal.S-N curve of Mg alloy weld joint is lower than sta...