孔洞对2519A铝合金焊接接头裂纹扩展的影响

Effects of Hole on Crack Growth Behavior of Welded Joints of Aluminum Alloy 2519A

建立了由焊缝和母材两个区域组成的含孔洞的焊接接头裂纹扩展仿真模型;研究了2519A高强铝合金焊接接头中孔洞形状、尺寸、位置对裂纹尖端应力强度因子的影响。结果表明:孔洞形状的影响取决于尖角顶点与孔洞中心连线和受力方向之间的最小夹角,夹角越大应力强度因子越大;随孔洞尺寸的增加应力强度因子增加;当孔洞中心与裂纹尖端连线和裂纹延长线之间的最小夹角一定时,孔洞离裂纹尖端越近应力强度因子越大。

The crack growth simulation model of welded joint of aluminum alloy 2519A was established, which was composed of two regions such as weld seam and base metal. The effects of hole shape, size and location on the crack tip of stress intensity factor were investigated. The results show that the shapes of the holes depend on the minimum angle that between the vertex of the sharp comers with holes center connection and direction of the force. The greater the angle is, the greater stress intensity factor value is. The stress intensity factor increases as the increase of hole size. When it is the minimum constant angle in which between the connection line of holes in the center with the crack tip and crack extension cord, the closer hole is from the crack tip, the stress intensity factor is greater.