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Abstract—The use of mixed formulations is a promising way to increase the efficiency of inhibitory protection of metals. Criteria for the additivity of the protective action of the components of mixed corrosion inhibitors, both their synergistic interaction and antagonism depend on the parameter used in evaluating the protection efficiency. Equations were proposed that make it possible to separate the effects of synergy and antagonism of inhibitors based on data on the degrees or terms of metal protection by each of the mixture components and the mixture itself. The synergism of the protective action is a direct recommendation for using the mixed inhibitor instead of each of its component. However, the absence of the synergism of protective action, and even an antagonism, is not always a contraindication for use of the mixture. Even an antagonistic mixture can provide more effective metal protection compared to its constituents. In the absence of specific interactions, the protective properties of the inhibitor mixtures always exceed the protective properties of their components. This superiority is higher with a greater effectiveness of mixed inhibitors. [ABSTRACT FROM AUTHOR]

Abstract—With the correct adjustment of conditions, thermal treatment of a magnesium alloy in 5-chloro-1,2,3-benzotriazole vapor can lead to the formation of nanosized adsorption inhibitor layers on its surface, which hydrophobicizes the metal surface and increase its corrosion resistance due to inhibition of the anodic process. The protective aftereffect of the adsorption layers of 5-chloro-1,2,3-benzotriazole depends on the temperature and duration of the chamber treatment. The temperature optimal for chamber treatment of the MA8–5-chloro-1,2,3-benzotriazole system is 150°C, and the optimal duration of treatment is 1 h. Protective films formed on a magnesium alloy during chamber treatment are capable of self-assembling under these conditions. The protective effect of adsorption films formed under optimal conditions increase with an increase in the time of exposure of the samples to heat. [ABSTRACT FROM AUTHOR]

Using a set of physicochemical (ellipsometry and contact angle measurements), electrochemical (potentiometric anode polarization and electrochemical impedance spectroscopy), and corrosion (periodic moisture condensation test) methods, the properties of adsorption films formed on the AMg6 aluminum alloy surface by the chamber method in vapors of some amines of heterocyclic compounds, carboxylic acids, and their salts are studied. It is established that the use of the studied compounds in the chamber processing of the alloy increases—though not effectively enough—its corrosion resistance in a humid atmosphere. The most promising inhibitors are carboxylic acids themselves; the optimum temperature for surface treatment with them is 140°C. One-hour treatment of steel with pairs of oleic, neodecanoic acid, and carboxylic acid A at this temperature gives rise to the formation of nanoscale adsorption films on the AMg6 alloy, which slightly hydrophilize the surface, but possess a protective aftereffect. Apparently, further improvement of chamber protection methods of the AMg6 alloy should consist in the selection of synergists for chamber corrosion inhibitors of the carboxylate type. [ABSTRACT FROM AUTHOR]

Using a set of physicochemical (ellipsometry and contact angle measurements), electrochemical (electrochemical impedance spectroscopy and polarization measurements), and corrosion (periodic moisture condensation and salt fog tests) methods, the properties of adsorption films formed on copper by the chamber method from vapors of benzotriazol (BTA), 1H-1,2,4-triazole, tolyltriazole (TTA), 5-chloro-1,2,3-benzotriazole (CBTA), 3-amino-1H-1,2,4-triazole, and 4-amino-1H-1,2,4-triazole at a temperature of 100°C are studied. It is shown that 1-h chamber treatment of copper with vapors of these compounds leads to the formation of nanoscale hydrophobic adsorption films on it, which inhibits the thermal growth of oxides, but stabilizes the passive state of the metal and increases its corrosion resistance. Among these different triazole compounds tested as chamber corrosion inhibitors, BTA and its substituted derivatives are distinguished. After a 1-h chamber treatment of copper, the protective aftereffect of the adsorption films of triazole derivatives grows symbatically with their saturated vapor pressure at the chamber treatment temperature, i.e., in the following increasing order: CBTA < TTA < BTA. This may indicate that the equilibrium adsorption films do not have time to form at 100°С on the metal within this time period. After a prolonged (24 h or more) chamber treatment of copper with vapors of substituted benzotriazoles, equilibrium adsorption films of inhibitors are formed on it. In this case, the influence of the chamber inhibitor properties on their protective aftereffect alternates. Under such conditions, the least volatile and most hydrophobic substituted benzotriazole, i.e., CBTA, provide the best metal protection. [ABSTRACT FROM AUTHOR]

The atmospheric corrosion resistance of metals can be reached by the formation of ultrathin protective films on their surface. Over recent years, a fundamentally new feasibility of the nanodimension films on metals capable of ensuring high atmospheric corrosion resistance of metals at least for the period of transportation and in-process storage of the metals was studied. The method of formation of such films by semivolatile nontoxic compounds capable of being adsorbed on metal surface from gas phase at increased temperature (chamber inhibitors) was proposed for this purpose. It is based on the use of such low-volatile organic inhibitors, which are prone to chemisorption on protected metal, and, as a consequence, can provide the stability of the adsorbed layers and long protection after-effect. It was shown by the complex of accelerated corrosion, electrochemical, and optical techniques that the treatment of zinc by vapors of low-volatile corrosion inhibitors at increased temperature and suitable compilation of the reagents results in the formation of the adsorption film with the effect of the long protection after-effect. [ABSTRACT FROM AUTHOR]

Atmospheric corrosion stability of metals can be achieved by coating their surfaces with superthin nanoscale layers. The scientific principles of inhibiting metal corrosion have been under development for many years, but a new direction of progress has emerged recently. The main achievement of research in this new direction is the possibility of covering metals in nanoscale films that, despite their extreme thinness, ensure high corrosion resistance of the metals under various atmospheric conditions. To this end, methods are suggested for producing such coatings from volatile organic compounds that can adsorb on metal surfaces from the gaseous phase. Increasing the irreversibility of adsorption of volatile corrosion inhibitors is necessary to strengthen the protective effect of the nanolayers they form on the surface. Nanolayer-coating protection has a number of fundamental advantages, including retention of article dimensions, a lack of a need for special utilization and degreasing methods, and affordability. [ABSTRACT FROM AUTHOR]