5182铝合金压印接头疲劳服役失效规律量化分析  

Quantitative analysis of fatigue service failure law of 5182 aluminium alloy clinched joints

作　　者：石也 雷蕾 闫明[1] 宋春雨 SHI Ye;LEI Lei;YAN Ming;SONG Chunyu(School of Mechanical Engineering,Shenyang University of Technology,Shenyang,110870,China)

机构地区：[1]沈阳工业大学,机械工程学院,沈阳110870

出　　处：《焊接学报》2025年第3期75-81,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金项目(52305397);辽宁省联合基金面上项目(2023-MSLH-238);辽宁省教育厅高等学校重点攻关项目(LJ212410142004)。

摘　　要：针对疲劳服役过程中的5182铝合金压印接头开展研究,通过动态响应—强度退化交替试验分阶段采集接头的固有频率,并测试接头在疲劳服役过程中的剩余静强度情况,借助固有频率变化量及强度退化规律,探究并量化压印接头疲劳退化的失效过程,基于剩余强度非线性理论模型和累积损伤模型探求接头服役失效的量化方法.结果表明,疲劳加载过程中压印接头固有频率曲线出现明显左移现象,随服役寿命的增加接头固有频率逐渐减小,其接头剩余强度同样出现对应减小变化.固有频率下降曲线和强度退化曲线走势大致相同,变化阶段分区明显,均呈现由平缓减小到急剧下降的过程.基于两种模型建立了压印接头疲劳服役强度退化理论公式,进一步得出5182铝合金压印接头剩余强度预测模型,经验证应用效果良好.创新点:(1)量化分析铝合金压印接头的渐进失效过程.(2)建立了铝合金压印接头剩余强度预测模型.This study investigates 5182 aluminum alloy clinched joints during fatigue service.The natural frequency of joints was periodically monitored through alternating dynamic response-strength degradation tests.The residual static strength was measured throughout the fatigue service process.The failure mechanism of fatigue degradation was quantitatively analyzed using natural frequency variations and strength degeneration laws.A quantitative method for joint service failure was established based on a nonlinear residual strength theoretical model and cumulative damage model.The results demonstrate that the natural frequency curve undergoes a significant leftward shift during fatigue loading.As the service life increases,the natural frequency of the joint gradually decreases,and the residual strength of the joint also decreases.The trend of the natural frequency and residual strength with the number of fatigue cycles is roughly the same,and the curve is clearly divided into stages.Both show a decreasing process from gentle to sharp.Based on the two models,a theoretical formula for the fatigue strength degradation of clinched joints was derived.A residual strength prediction model for 5182 aluminum alloy clinched joints was further established,and it shows validated practical effectiveness.Highlights:(1)Based on the welding numerical simulation,a step-cooling laser welding system was designed.(2)A predictive model for the residual strength of aluminium alloy clinched joints was developed.

关 键 词：压印连接 铝合金 动态响应 固有频率 强度退化 

分 类 号：TG405[金属学及工艺—焊接] TG386.34