ABSTRACT

Adhesive joints usually experience different thermal conditions not only during their service life but even also when the joints are stored, and no external force is applied. One of the main concerns for such a condition is the residual strains/stresses induced into the adhesive layer due to the cyclic ambient temperature. In this research, the effects of residual strains on the static strength of dissimilar single lap adhesive joints (SLJ) are experimentally investigated. The thermal cycles were applied in an aluminum/carbon fiber-reinforced polymer (Al/CFRP) adhesively bonded SLJ with different adhesive thicknesses. Residual strains due to the differential thermal contraction of the two materials were measured inside the adhesive layer using the digital image correlation (DIC) technique. It was shown that for the studied conditions, the residual strains increase by thermal cycles, leading to a decrease in residual static strength of the joints. A 2D finite element thermal analysis was also performed and the numerical data were compared with the experimental results.

摘要

胶接接头通常不仅在其使用寿命期间，甚至在接头存放且不施加外力时都会经历不同的热条件。这种情况的主要问题之一是由于循环环境温度而在粘合剂层中引起的残余应变/应力。在这项研究中，残余应变对不同单搭接粘合接头 (SLJ) 静态强度的影响进行了实验研究。热循环应用于具有不同粘合剂厚度的铝/碳纤维增强聚合物（Al/CFRP）粘合的 SLJ。使用数字图像相关 (DIC) 技术在粘合剂层内测量由于两种材料的不同热收缩引起的残余应变。结果表明，对于所研究的条件，残余应变因热循环而增加，导致接头残余静强度降低。还进行了二维有限元热分析，并将数值数据与实验结果进行了比较。