Research On Theory And Process Of Fatigue Strengthen Of Interference-fit For Aircraft Wall-riveting

Because it doesn't increase the weight and needn't change the material, Interference-fit riveting technology can exponentially improve the fatigue life of aircraft riveting structure. It was paid more attention in the long life manufacturing of modern aircraft. Research on interference-fit riveting technology for increasing the service safety and service durability of the aircraft is of great significance. Based on interference-fit riveting about stress analysis, finite element simulation, fatigue test of the riveting process and data statistics, studying the strengthen mechanism of interference-fit and the selection of process parameter in-depth.Using the theory of elastic-plastic mechanics, the mathematical model between the quantity of interference and the stress for the hole of interference-fit riveting structure was established and the stress distribution of the interference-fit was obtained. The validity of the theory of stress analysis was verified by finite element simulation of interference-fit riveting structure. From the view of stress analysis combined with finite element simulation of the actual riveting structure model, the reason of improving the fatigue life of interference riveting structure is: under the external alternating load, residual tangential tensile stress after interference riveting reduces the amplitude of alternating stress of the hole. The influence law between process parameters, including accuracy the height of rivet driving head, the diameter of hole, and the fatigue life of riveted structure are found by fatigue test. Within a certain range, with the decrease of the height of rivet driving head or the diameter of hole, the fatigue life of riveting structure is rising. The influence law between the quantity of interference and the fatigue life was also found by fatigue test and interference measuring experiment of Interference-fit riveting test pieces. The highest fatigue life of the interference riveting structure was acquired when the quantity of interference is controlled in 4% ~ 5%.