打偏对预穿孔自冲铆接接头的成形质量和力学性能的影响
Effects of riveting misalignment on forming quality and mechanical properties for pre-punched self-piercing riveted joints
于万元 1王超 2李卓2
作者信息
- 1. 柳州职业技术大学汽车工程学院,广西 柳州 545001
- 2. 湖南大学整车先进设计制造技术全国重点实验室,湖南 长沙 410082
- 折叠
摘要
面对日益严格的碰撞安全法规要求,钢-铝混合车身中的薄壁结构需采用多层高强度钢板,然而传统自冲铆接技术无法实现多层高强度钢板的有效连接.采用预穿孔自冲铆接技术实现了厚度为1.2 mm高强度钢DP780、厚度为1.2 mm高强度钢DP590和厚度为3.0 mm压铸铝合金Al Si10Mn Mg-T7的三层板连接,并系统分析了不同打偏参数对预穿孔自冲铆接接头的成形质量、力学性能和失效机理的影响.结果表明:打偏会导致铆钉与板材无法形成有效的机械互锁,导致承载能力显著下降;打偏侧的铆钉严重镦粗变形,并且无法刺穿中层钢板,仅有部分位置产生机械互锁;相较于正常对准铆接的接头的机械互锁失效,打偏接头的失效中未观察到塑性变形和材料失效;相较于正常对准铆接的接头的力学性能,打偏接头的剪切和十字拉伸峰值力分别降低了57%和52.3%以上.
Abstract
For the increasingly stringent collision safety regulations,the multi-layer high-strength steel sheets is required in the thin-walled structures of steel-aluminum hybrid bodies,however,the multi-layer high-strength steel sheets cannot be effectively joined by conventional self-piercing riveting(C-SPR)technology.Therefore,the three-layer sheet connection of high-strength steel DP780 with a thickness of 1.2 mm,high-strength steel DP590 with a thickness of 1.2 mm and die-casting aluminum alloy Al Si10Mn Mg-T7 with a thickness of 3.0 mm was achieved by pre-punched self-piercing riveting(PH-SPR)technology,and the influences of different riveting misalignment parameters on the forming quality,mechanical properties and failure mechanism of PH-SPR joints were analyzed systemat-ically.The results indicate that riveting misalignment leads to the ineffective mechanical interlock between rivets and sheets,resulting in a significant decrease in load-bearing capacity.The rivets on the off side are severely deformed in upsetting and unable to penetrate the middle steel sheet,with only some positions experiencing the mechanical interlock.Compared to the mechanical interlock failure of normally aligned riveted joints,no plastic deformation or material failure is observed in the failure of misaligned joints,and compared to mechanical properties of normally aligned riveted joints,the shear and cross-tension peak forces of misaligned joints are reduced by over 57%and 52.3%,respectively.
关键词
高强度钢/预穿孔自冲铆接/成形质量/失效机理/力学性能Key words
high-strength steel/pre-punched self-piercing riveting/forming quality/failure mechanism/mechanical properties引用本文复制引用
出版年
2025
NETL
NSTL
万方数据