Effect of Riveting Gap on Fatigue Life of Composite Single Nail Joint

In order to evaluate the fatigue strength of rivet connection composites, carbon fiber T800 plates were connected by stainless steel single row rivets. The fatigue tests were carried out on composite single-nail joints by low-cycle fatigue testing machine, and the rivet connection joints were broken. The macroscopic inspection and microscopic observation of the composite single-nail connection joints were carried out, the stress analysis was carried out by finite elements, and the fatigue life of rivet joints was predicted by the stress severity coefficient method, so as to determine the fracture properties and causes of the connecting joints, and to predict the fatigue life of rivet joints. The results show that in the fatigue experiment of single-nail connection composites, the rivet is plastically deformed during the application of load, and the main failure form is shear fatigue failure. The size of the riveting gap affects the fatigue life of the composite single-nail joint. At the same time, the thickness of the specimen will reduce the maximum inclination of the rivet caused by the riveting gap, which will jointly affect the fatigue life of the composite single-nail joint. The minimum error between the rivet joint model prediction and experimental results is 3.4%, and the maximum error is 16.8%.