Different adhesive bonding methods have been prominently used in aerospace applications since the 1980s because adhesively bonded joints are regarded as an alternative to traditional bonding methods. However, the effects of fatigue on adhesively bonded joints – one of the most significant issues in the aerospace industry – are still currently being investigated. This study experimentally investigated the lifetimes of single-lap joints (SLJs) of five different adherend thicknesses (2, 3, 4, 5 and 6 mm) – obtained using AA2024-T3 aluminum alloy and DP460 structural adhesive – under varying tensile fatigue loads. Accordingly, before performing fatigue tests, static tensile strength tests were carried out on the SLJs to determine the maximum loads to be used for tensile fatigue tests and also to evaluate their quasi-static performances. The fatigue tests were performed at a loading ratio (R) of 0.1 and a frequency of 20 Hz. The static tensile strength of the joints was found to increase by approximately 22% with increasing adherend thickness. However, this increase was not the same as the increase in adherend thickness. In addition, increased adherend thickness was observed to change the maximum load applied to the joints over infinite cycles (taken to be 10⁶ cycles). This was because the change in adherend thickness changed the bending moment formed in the joint and the flexural rigidity of the adherend.

自1980年代以来，在航空航天应用中已广泛使用了不同的粘合方法，因为粘合接头被认为是传统粘合方法的替代方法。但是，目前仍在研究疲劳对粘合接头的影响-航空航天工业中最重要的问题之一。这项研究通过实验研究了五种不同厚度（2、3、4、5和6毫米）（使用AA2024-T3铝合金和DP460结构粘合剂）在不同的拉伸疲劳载荷下的单搭接接头（SLJ）的寿命。因此，在进行疲劳测试之前，对SLJ进行了静态拉伸强度测试，以确定用于拉伸疲劳测试的最大载荷，并评估其准静态性能。疲劳试验是在0.1的负载比（R）和20 Hz的频率下进行的。发现接头的静态抗拉强度随被粘物厚度的增加而增加约22％。但是，该增加与被粘物厚度的增加不同。此外，观察到增加的被粘物厚度会改变无限循环中施加到关节的最大载荷（取为10⁶个周期）。这是因为被粘物厚度的变化改变了在接头中形成的弯曲力矩和被粘物的抗弯刚度。