热影响区几何尺寸对铝合金焊接接头变形及强度影响规律

摘要

FEM was utilized on the aluminum alloy flat buttdwelded joint with ABAQUS software and the effects of HAZ geometrical dimension on aluminum alloy joint＇s deformation and strength were studied.The results indicate that with the increasing of HAZ＇s length,the yield stress and tensile stress of the joints both decrease gradually.The stress traxiality lays mutation between the base material and HAZ and between the weld metal and HAZ.At the same time,the position of the maximum stress traxiality is from the boundary between the base material and HAZ to the boundary between the weld metal and HAZ.With the increasing of thickness of joint,both the yield stress and tensile stress of the joints increase gradually.The stress traxiality of the joints depends on the thickness of specimen,dimension of weld metal and dimension of HAZ.With the increasing of width and gauge of joints,the yield stress,the tensile stress and the maximum stress traxiality increase basically.When the gauge of joints increases to certain value,the yield stress,the tensile stress and the maximum stress traxiality remain constant basically.%用有限元软件ABAQUS对平板对接铝合金焊接接头进行拉伸模拟,研究了HAZ几何尺寸对焊接接头变形及强度影响规律.结果表明,随着HAZ长度的增加,铝合金焊接接头的屈服强度和抗拉强度均逐渐降低,应力三轴度在母材与HAZ交界处和焊缝与HAZ交界处存在突变,应力三轴度最大值的位置从母材与HAZ交界处转变为焊缝与HAZ的交界处;随着接头厚度的增加,屈服强度和抗拉强度基本上是逐渐增大的,接头中的应力三轴度取决于试样的厚度、焊缝区尺寸及HAZ尺寸;随着接头宽度及标距长度的增加,屈服强度、抗拉强度和焊缝及HAZ范围内的应力三轴度基本上是逐渐增大的.当试样标距长度增加到某一值时,这三个参数将不再发生变化,为一恒值.