Field and accelerated tests of contact and volatile inhibitors of atmospheric corrosion with various metals

Effect of hydrogen peroxide on crack growth rate in X70 pipeline steel in weak acid solution

“…The character of the changes in the i p value as a function of the H 2 O 2 concentration at E cor and E = –0.45 V SHE is the same, but the maximum of the i p – C Ox dependence is more strongly pronounced at a constant potential (curve 2). Maximum points on the i p – C Ox dependence were observed previously in acidic environments in the presence of different oxoacids (HOx) and attributed to the dissociation of HOx molecules in the inner part of the electric double layer (EDL) with the formation of high-energy hydrogen ions, which are later discharged on the metal surface [15,23–26]. At the same time, hydrogen (hydronium) ions from the bulk solution are adsorbed on the outer surface of the dense EDL part, and the discharge process is hampered as it requires the permeation of the ions directly to the metal surface.…”

“…The critical concentration of hydrogen peroxide ( C Ox,crit ) in a particular environment can be calculated according to reference [13,16,23,26,27]: where , and are the concentrations of H + , and ions respectively; , and are the diffusivities of H + , , ions, and hydrogen peroxide, respectively; m is the number of hydrogen ions formed as a result of ion dissociation; and P is the number of hydrogen ions consumed in the reduction of a hydrogen peroxide molecule.…”

Pitting corrosion of aluminium in the tropical climate of Mauritius

“…Moreover, it has been reported that the corrosion of aluminium corrosion depends primordially on the atmosphere being contaminated (in general by sulphur dioxide or chlorides). This is due to the fact that it is only in such contaminated atmospheres that the TOW has a significant impact on the atmospheric corrosion of aluminium [33]. Other studies performed by Budov [34] and Berukshtis and Klark [35] have shown that sulphur dioxide and chloride levels are the most important factors influencing the atmospheric corrosion of aluminium and, depending on the level of atmospheric contamination, the corrosion rate of aluminium can vary up to 72 times.…”

Volatile inhibitors of atmospheric corrosion. III. Principles and methods of efficiency estimation

“…In fact, air-tight polyethylene packing can sometimes provide efficient metal protection in the absence of inhibitors by shielding it from exposure to moisture or other corrosive environment components [24]. Obviously, the tests described above do not reflect this capability of polymer films, papers, and composite materials on their basis.…”

“…Despite the external similarity, this phenomenon cannot be considered as vapor-phase corrosion inhibition. Corrosion inhibitors are compounds and combinations that, when present in a sufficient concentration in a corrosion system, can decrease the corrosion rate of metals without changing considerably the concentration of any corrosion agent, such as oxygen and water [23,24].…”