Aerospace Technic and Technology

Corrosion of aircraft structures is one of the main factors limiting the duration of their operation, affecting on the economic efficiency and safety of air transport. Corrosion protection is performed at the stage of manufacturing aircraft structures, during their repair and operation. One of the additional measures of anti-corrosion protection is the use of film-forming coatings, which displace moisture from the gaps of structural joints, form a protective film, and also slow down the corrosion process. The protective properties of film-forming coatings are investigated by standard corrosion tests. At the same time, the specifics of aircraft structures and the possible side effects of the use of anti-corrosion compounds require special studies. The article presents an analysis of works in which the effect of film-forming anticorrosive compounds on the fatigue of elements of aircraft structures is considered.The main type of joints in the structure of modern aircraft are riveted joints. The high penetrating ability of film-forming materials ensures their penetration into the gaps of riveted joints, which, in some cases, can affect the frictional forces between the connected elements, which ensure the integrity of the joints. In some experimental investigations, the influence of film-forming compositions on the kinetics of fatigue crack growth is noted as a side effect. A number of possible mechanisms of deceleration and acceleration of the rate of crack propagation are considered. Experimental data concerning the effect of anticorrosive compounds on the fatigue of riveted joints and the process of propagation of fatigue cracks in structural materials, indicate the need to develop a universal methodology for the selection and use of film-forming compositions for the protection of aircraft structures from corrosion, taking into account the minimization or prevention of negative side effects on the service life of aircraft.

fatigue; corrosion; riveted joints; film-forming anticorrosion compounds; side effects

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