Abstract Adhesively bonded joints are used in many engineering applications and are manufactured by joining various materials together. Static and dynamic analysis of adhesively bonded joints is very important in both scientific and sector studies on these joints. In this study, the static and fatigue strengths of single-lap joints (SLJs) and three-step-lap joints (TSLJs) that were subjected to tensile and four-point bending tests were examined experimentally and numerically. Adhesively bonded joints were produced using DP460 toughened type adhesive and AA2024-T3 aluminum alloy was used as the adherent. Fatigue tests were performed at a loading ratio (R) of 0.1 and a frequency of 10 Hz. As a result, applying a step-lap to the overlap area of adhesively bonded joints considerably increased the tensile static and fatigue strength of the joint. For the single-lap joint, both the static tensile and the tensile fatigue lifetime limit value of the three-step-lap joint increased approximately 100%. One of the reasons for that increase was that the moment effect formed in single lap joints due to the eccentric loading is minimized and the other is that a step-lap applied to the overlap area retards the formation of damage. However, static bending and fatigue strength values of TSLJs significantly decreased compared to those of SLJs. In addition, the results of the experimental and numerical analyses were found to be highly compatible with each other.

中文翻译：

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粘接阶梯搭接接头疲劳性能的研究：实验和数值分析

摘要 粘接接头在许多工程应用中都有使用，是通过将各种材料连接在一起而制成的。粘接接头的静态和动态分析在这些接头的科学和行业研究中都非常重要。在这项研究中，经过拉伸和四点弯曲试验的单搭接接头 (SLJ) 和三阶搭接接头 (TSLJ) 的静态和疲劳强度进行了实验和数值检验。胶接接头采用DP460增韧型胶粘剂制作，胶粘剂为​​AA2024-T3铝合金。疲劳测试在 0.1 的负载比 (R) 和 10 Hz 的频率下进行。因此，在粘接接头的重叠区域应用阶梯搭接大大提高了接头的静态拉伸强度和疲劳强度。对于单搭接接头，三阶搭接接头的静态拉伸和拉伸疲劳寿命极限值均增加了约 100%。增加的原因之一是由于偏心载荷在单搭接接头中形成的力矩效应被最小化，另一个原因是应用于重叠区域的阶梯搭接延迟了损坏的形成。然而，与 SLJ 相比，TSLJ 的静态弯曲和疲劳强度值显着降低。此外，发现实验和数值分析的结果彼此高度兼容。增加的原因之一是由于偏心载荷在单搭接接头中形成的力矩效应被最小化，另一个原因是应用于重叠区域的阶梯搭接延迟了损坏的形成。然而，与 SLJ 相比，TSLJ 的静态弯曲和疲劳强度值显着降低。此外，发现实验和数值分析的结果彼此高度兼容。增加的原因之一是由于偏心载荷在单搭接接头中形成的力矩效应被最小化，另一个原因是应用于搭接区域的阶梯搭接延迟了损坏的形成。然而，与 SLJ 相比，TSLJ 的静态弯曲和疲劳强度值显着降低。此外，发现实验和数值分析的结果彼此高度兼容。