摘要
7075-T6 aluminum alloy/low carbon steel joint was carried out via a novel friction plug−riveting spot welding process.This process utilized uniquely designed steel rivets with a tip and groove shape.The macro-morphology formation,microstructure,microhardness and lap shear performance of joints were investigated.As the spindle down distance increased,the rivet tip was friction welded with the lower steel sheet,resulting in the formation of a solid phase welding zone exhibiting metallurgical bonding.Additionally,a hook was formed in the joint,providing the mechanical locking.The results showed that under optimal parameters of spindle down distance of 3.4 mm,rotation speed of 4000 r/min,and spindle down speed of 2.4 mm/s,the lap shear load of the joints reached a maximum of 14.36 kN.Failure occurred at the aluminum alloy base metal.
采用一种基于具有尖状底端和凹槽头部形状的钢制铆钉的新型摩擦塞−铆复合点焊工艺,对7075-T6铝合金/低碳钢异种金属进行焊接。研究接头的宏观形貌、微观形貌、显微硬度和搭接剪切性能。随着主轴下压距离的增加,铆钉尖端与下层钢板发生摩擦焊接,形成具有冶金结合的固相焊接区。此外,接头处形成的钩子状结构为机械连接提供了可能。实验结果表明,在3.4 mm的主轴下压距离、4000 r/min的主轴转速和2.4 mm/s的主轴下压速度的优化工艺参数组合下,接头的最大搭接剪切载荷能达到14.36 kN,该接头在铝合金母材中发生失效。
基金
supported by the National Natural Science Foundation of China(No.51875037).
