摘要
以A7N01铝合金焊接接头为研究对象,基于最大周向应力准则,通过数值模拟的方法对接头裂纹在Ⅰ-Ⅱ复合加载下的扩展路径进行了研究,其中重点分析了当裂纹扩展到焊缝与母材之间的界面时,复合加载角度α对其启裂角度θ的影响.结果表明:在Ⅰ-Ⅱ复合载荷作用下,接头裂纹扩展到界面时,其扩展方向存在三种可能性:一是继续在焊缝中扩展;二是沿着界面方向扩展且不进入母材;三是穿过界面且进入母材.当α=30°时,裂纹在界面处的启裂角θ约为0°,裂纹将沿着界面的方向扩展且不进入母材;当α=45°时,裂纹在界面处的启裂角θ约为30°,裂纹将穿过界面且进入母材;当α=60°时,裂纹在界面处的启裂角θ约为41°,裂纹将穿过界面且进入母材.
Taking the welded joint of aluminum alloy A7N01 as investigation object and based on the maximum circumferential stress criterion, the crack propagation path in the joint was investigated under the condition ofⅠ-Ⅱcomposite loading by means of numerical simulation, where the effect of composite loading angle α on crack initiation angle θ was emphatically analyzed when the crack extends through to the interface between the weld and matrix metal. The result showed that under the condition ofⅠ-Ⅱcomposite loading and when the cracks of the joint extend through to the interface, there would be three passibilities of crack propagation direction in the joint: one being continuous propagation in the weld, the other-propagation along the interface without entering the matrix metal;and the third-propagation across the interface and entering the matrix metal. When α=30°, the crack initiation angle θ at the interface would be about 0° and the crack would spread along the direction of the interface without entering the matrix metal when α=45°, the crack initiation angle at the interface θ would be about 31° and the crack would propagate across the interface and enter the parent material;when α=60°, the crack initiation angle θ at the interface would be about 41° and the crack would pass through the interface and enter the matrix metal.
作者
李有堂
王亚东
LI You-tang;WANG Ya-dong(College of Mechano-Electronic Engineering,Lanzhou Univ.of Tech.,Lanzhou730050,China)
出处
《兰州理工大学学报》
CAS
北大核心
2019年第2期160-165,共6页
Journal of Lanzhou University of Technology
基金
国家自然科学基金(71461018)
关键词
A7N01铝合金
焊接接头裂纹
扩展路径
加载角度
启裂角
A7N01 aluminum alloy
crack in welded joint
propagation path
loading angle
crack initiation angle
