CFRP-铝合金单搭接胶接接头拉伸剪切性能及疲劳失效模式分析  

Tensile Shear Performance and Fatigue Failure Mode Analysis of CFRP-aluminum Alloy Single-lap Adhesive Joints

作　　者：张瑶[1] 阳玉球 高聪 ZHANG Yao;YANG Yu-qiu;GAO Cong(College of Textiles,Donghua University,Shanghai 201620;Chongqing Changan Automobile Co.,Ltd,)

机构地区：[1]东华大学纺织学院,上海201620 [2]重庆长安汽车股份有限公司,重庆400023

出　　处：《纺织科学与工程学报》2024年第4期65-72,共8页Journal of Textile Science and Engineering

摘　　要：在汽车生产过程中,为减少应力集中或提升结构刚度,很多零部件采用胶接方式进行连接,但胶接结构容易出现损伤积累,使连接部分出现整体破坏现象,研究胶接接头的疲劳性能对保证汽车零部件的长时间服役性能具有重要意义。设计胶接厚度为0.5 mm、1.5 mm和2.5 mm以及搭接长度为12.5 mm和25 mm的碳纤维增强树脂复合材料(CFRP)-铝合金单搭接胶接接头,进行准静态拉伸和疲劳实验。基于疲劳实验结果和双参数Weibull分布,对接头的应力-寿命(S-N)曲线进行拟合,分析其破坏模式及破坏形貌,揭示CFRP-铝合金单搭接接头在疲劳载荷下的失效模式和破坏机制。研究发现,接头的静态拉伸结果对胶接厚度变化不敏感,对搭接长度变化较为敏感;搭接长度从12.5 mm变化至25 mm时,接头的疲劳极限载荷从555.14 N变为1446.10 N,疲劳极限载荷随着搭接长度变化效果明显;随着胶接厚度变化,失效模式由内聚失效转化成界面失效,随着搭接长度变化,失效模式由胶层内聚失效转化成混合失效。In the domain of vehicle manufacturing,the adhesive bonding of components is extensively utilized to mitigate stress concentration or enhance local structural rigidity.Nevertheless,adhesive structures are prone to damage accumulation,leading to overall failure in the connection areas.It is crucial to investigate the fatigue performance of adhesive joints to ensure the long-term serviceability of automotive components.In this study,CFRP(carbon fiber reinforced polymer)-aluminum alloy single-lap adhesive joints were designed with adhesive thicknesses of 0.5 mm,1.5 mm,and 2.5 mm and overlap lengths of 12.5 mm and 25 mm,and quasi-static tensile and fatigue tests were conducted.Based on the fatigue test results and the two-parameter Weibull distribution,the stress-life(S-N)curves of the joints were fitted,and their failure modes and morphologies were analyzed to reveal the failure modes and mechanisms of CFRP-aluminum alloy single-lap adhesive joints under fatigue loading.Results showed that the static tensile results of the joints were not sensitive to changes in adhesive thickness but were sensitive to changes in overlap length.When the overlap length changed from 12.5 mm to 25 mm and the fatigue limit load of the joint increased from 555.14 N to 1446.10 N,a significant effect of overlap length on the fatigue limit load appeared obviously.With changes in adhesive thickness,the failure mode converted from cohesive failure to interfacial failure,and with changes in overlap length,the failure mode converted from cohesive failure in the adhesive layer to mixed failure.

关 键 词：CFRP 单搭接 胶接 疲劳性能 失效模式 

分 类 号：TB332[一般工业技术—材料科学与工程] TG496[金属学及工艺—焊接]