摘要
采用超声深滚工艺处理了2A12铝合金、2A11铝合金的超声波焊缝,通过扫描电镜和透射电镜观察、纳米硬度测试、残余应力测试、有限元应力分析和拉伸试验等方法,研究了焊缝处理前后的组织结构和力学性能。结果表明:超声深滚处理可以去除焊缝表面的超声波焊接压痕,降低焊缝表面的应力集中。超声深滚处理后,结合界面的焊接残余应力由处理前焊接状态的56 MPa转变为处理后的-44 MPa。此外,超声深滚处理产生的塑性变形使结合界面发生进一步的动态回复,形成较为均匀的层状亚晶组织。超声深滚处理后,超声波焊缝的平均结合拉伸力提高了约36%。
The Ultrasonic Welding(USW) joints of 2A12 and 2A11 aluminum alloy ae processed by Ultrasonic Deep Rolling(UDR) technique,and then microstructure and mechanical properties of the USW joints before and after UDR are investigated via the observation of scanning electron microscopy and transmission electron microscopy,nano-hardness test,residual stress test,finite element stress analysis and tension test.Results show that the ultrasonic welding impressions at the USW joints surface can be eliminated by the UDR treatment,resulting in reduced stress concentration.The residual stress at the bonding interface transforms from 56 MPa at the as-welded state before the treatment into-44 MPa after the UDR treatment.Additionally,further dynamic recovery is developed due to severe plastic deformation caused by the UDR treatment,and resulted in more homogeneous lamellar subgrains at the bonding interface.The average bonding tension force of the USW joints has increased by about 36% after the UDR treatment.
出处
《装甲兵工程学院学报》
2013年第4期86-90,共5页
Journal of Academy of Armored Force Engineering
基金
军队科研计划项目
关键词
超声波焊接
超声深滚
焊接压痕
焊接残余应力
结合拉伸力
ultrasonic welding
ultrasonic deep rolling
welding impression
welding residual stress
bonding tension force
