工程设计学报2025，Vol.32Issue(3)：359-366,8.DOI:10.3785/j.issn.1006-754X.2025.04.177
热处理对铝合金自冲铆接头裂纹和力学性能的影响
Influence of heat treatment on cracks and mechanical properties of self-piercing riveted joint in aluminum alloy
摘要
Abstract
Aiming at the problem that cracks were prone to occur at the bottom of the self-piercing riveted joint in 2024 aluminum alloy,the crack formation mechanism was analyzed through riveting experiments,and the crack suppression was investigated by combining the annealing and riveting processes of the 2024 aluminum alloy sheet.Meanwhile,the microstructure and mechanical properties of the joints were compared,and the fracture characteristics of the joints were analyzed using scanning electron microscopy(SEM)to explore their failure mechanism,thereby analyzing the influence of heat treatment process on the mechanical properties and failure forms of the joints.The results showed that the plasticity and ductility of the 2024 aluminum alloy sheet increased after annealing treatment at 360℃,while the hardness decreased by 23.6%.In the case of riveting the 2024 aluminum alloy sheet without annealing treatment,the crack initiation occurred at the rivet tube leg tip area,and macro cracks appeared along the radial direction at the joint bottom.After annealing treatment,there were no obvious cracks at the joint bottom,which significantly improved the sealing performance and corrosion resistance of the connection point.The grain structure of the joint section in the unannealed group was coarse and irregular,and the deformation at the rivet tube leg tip area was significant.In contrast,the grain structure of the joint section in the annealed group was refined and more uniform.Although the static strength of the joints decreased by 12.93%after annealing treatment,the failure displacement and energy absorption values increased by 27.3%and 19.31%,respectively.The failure mode transformed from complete fracture of the upper plate to tearing of the lower plate,with the bottom of the connection point being pulled through by the rivet clinch.Additionally,the fracture mode changed from brittle fracture to ductile fracture.The research results can provide important references for the application of self-punching riveting process in fields such as automobiles and aerospace.关键词
2024铝合金/自冲铆接头/裂纹/热处理工艺/力学性能/失效形式Key words
2024 aluminum alloy/self-piercing riveted joint/crack/heat treatment process/mechanical property/failure mode分类
金属材料引用本文复制引用
邢保英,陈锦聪,阎治铭,张洪申,曾凯,邹春芽..热处理对铝合金自冲铆接头裂纹和力学性能的影响[J].工程设计学报,2025,32(3):359-366,8.基金项目
国家自然科学基金资助项目(52065034) （52065034）
云南省基础研究计划资助项目(202401AT070350) （202401AT070350）
