Influence of an anodized layer on the adhesion and surface protective performance of organic coatings on AA2024 aerospace Al alloy

Influence of electrode arrangement method on specific energy consumption and productivity in electrosynthesis of fine graphite powder

“…Between the electrodes is a working medium-a strong electrolyte: aqueous solutions of soluble salts. On the upper part of the electrodes there are current leads (4), which are connected to a direct current source through a diode. The electrolyte is a 15÷25 % aqueous solution of soluble salts.…”

“…During operation, aircraft, in addition to force influences, are continuously exposed to an extensive complex of external physical influences of a heterogeneous type: ionizing and radio emissions, large differences in thermal disturbances, harmful effects of electrodynamic and gravitational fields, geomagnetic and ionospheric factors [4][5][6][7]. Therefore, the creation of an external multifunctional coating for the protection of rocket and space objects, which has a huge range of possibilities for reflection and absorption from external negative factors, is an urgent task in modern aerospace engineering.…”

The long‐term corrosion performance and adhesion properties of 7B04 aluminum alloy/anodic film/epoxy primer system in acidic NaCl solution

“…To prevent corrosion of aircraft aluminum alloy structure, the aluminum alloy substrate usually needs to be pretreated and then coated with organic coatings. [ 1–3 ] Among the existing pretreatment methods, anodizing technology is relatively mature and has been widely used in aerospace industries. [ 4–7 ] Using organic coatings to protect aluminum alloys has been considered an economically feasible and suitable method in the past decades.…”

“…[ 4–7 ] Using organic coatings to protect aluminum alloys has been considered an economically feasible and suitable method in the past decades. [ 3 ] Currently, chromium‐free high‐solids epoxy primers are being used more and more to meet the requirements of environmental protection and corrosion resistance in aerospace industries. The intact organic coatings can isolate the aluminum alloy from the corrosive medium, but the penetration of water and corrosive ions will cause the deterioration of the coatings, resulting in the weakening or loss of anticorrosion properties.…”

“…To figure out the corrosion mechanism of metal/coating system and quickly evaluate its corrosion resistance, accelerated test methods, such as immersion test, [ 2,11–13 ] salt spray test, [ 1,2,14–16 ] and CASS spectrum test [ 17 ] have been widely used, and the evaluation methods can be visual, [1, 13,15 ] electrochemical, [ 2,3,11,14,16 ] mechanical, [ 3,14 ] and so on. Among them, the traditional electrochemical impedance spectroscopy (EIS) technology has become one of the most effective tools to study the degradation process of the metal/coating system, [ 2,16 ] but its disadvantage is that the measured electrochemical signal is the average information of the measured area, and cannot provide the information of local microscopic corrosion reaction.…”