Fatigue failure behaviour of bolted joining of carbon fibre reinforced polymers to titanium alloy

Carbon fibre reinforced polymers are widely used in industry, the problem of joining them with metal materials becomes significant. This is because of the loosening of bolted joints under applied loads, leading to a rapid reduction in fatigue life and even structural failure accidents. This study focuses on fatigue failure mechanisms of bolted joints of carbon fibre reinforced polymers to titanium alloy and looking for a novel solution to improve the fatigue life of bolted joints. Firstly, fatigue life prediction of the components is conducted based on FE-SAFE. Then, experiments are conducted to verify simulation results. Finally, the thread damage and the fracture morphology are analysed after tests. It is found that the fatigue life of bolted joints can be improved by increasing the stiffness of connected parts and choosing appropriate geometric parameters.