Thermal Fatigue Analyses of Riveted Structures

In this study, the effects of thermal fatigue loading on the riveted structures made of 2014, 2024, 6061 and 7075 aluminum alloys which are widely used in the aviation industry have been investigated. An algorithm has been developed under ANSYS finite element analysis software to determine the behavior of these structures that are exposed repeated thermal loading. This algorithm is based on the principle of determining the distribution of the safety factor on the material subjected to the thermal fatigue load. In the study, the rivet spacing (RS), the rivet edge distance (ED) and the rivet hole diameter (RD) were selected as riveting parameters. It is aimed to determine the optimum values of the parameters used under thermal fatigue loading and the most suitable one for this loading among the materials used. It is seen that 7075 aluminum alloy has the highest safety factor distribution for all the models in which the effect of these parameters was investigated. It has been determined that when the rivet spacing is 3 times the rivet diameter (3d), the highest safety factor value is obtained for all material types. And this value decreases when the rivet spacing is increased. When the effect of the rivet edge distance is examined, it is seen that when the rivet edge distance 8d is used, the highest safety factor value is obtained. The safety factor value is the smallest when the rivet edge distance is 2,5d. In addition, when rivet hole diameter increased from 2.5 mm to 4.8 mm, it was determined that safety factor value increased.