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Describes methods of accelerated corrosion testing currently being used in the world today and the cabinets available in which to perform the tests. Compares the tests and looks at the results obtained from them, looking at constant salt‐spray testing ASTM B117, cyclic wet/dry Prohesion and the multi‐function automotive cyclic corrosion test which incorporates salt‐spray cycles and high humidity cycles. Gives test results comparing constant salt‐spray to cyclic Prohesion to natural outdoor exposure.

Examines accelerated methods for the corrosion testing of materials, coatings and surface treatments used in the aerospace and defence industries. The drawbacks with some current accelerated corrosion tests are examined, particularly the problems experienced with neutral salt spray tests. Specific examples are given which identify the acute discrepancy between salt spray and marine exposure in the corrosion testing of metallic coatings on steels. Examines some recent advances in corrosion testing of aerospace materials, pre‐treatments and organic coatings, and outlines some preliminary research conducted at DERA Farnborough in developing more accurate test methods.

Salt‐spray testing, in which specimens or actual articles are contained in a closed cabinet and exposed to the ‘fog’ produced by the atomisation of a salt solution, is probably the most widely used method of accelerated corrosion testing in industrial laboratories. Many other salt‐spray‐testing techniques have been developed and used, but this short survey will be limited to consideration of the so‐called ‘salt‐fog’ testing method.

The purpose of this paper is to study the effect of surface salt spray duration on the fretting wear and electrochemical corrosion behaviors of Inconel 690 alloy.

A high-temperature steam generator was applied to salt spray test samples, a fretting wear rig was used to realize the damage behavior tests, an electrochemical workstation was applied to analysis the changes of each sample’s corrosion dynamic response before and after fretting wear.

The thickness of the oxide film that formed on sample surface was increased with the salt spray duration, and somewhat it could act as lubrication during the fretting wear process; however, the corrosive chloride would accelerate the fretting mechanical damage behavior.

In a salt steam spray condition, the fretting tribo-corrosion behaviors of Inconel 690 alloy surface was studied.

It is now fairly well established that steel reinforcements need some additional protection and various types of coatings such as fusion‐bonded epoxy, galvanizing and cement slurry have been used. Evaluation of such coated rebars in aggressive marine conditions is done usually by conducting some accelerated corrosion tests. These accelerated corrosion tests cannot be truly representative of field conditions and they often give higher corrosion rates. Validity of such tests becomes questionable. In the present work, corrosion rates of cement slurry‐coated rebars, obtained by ASTM impressed voltage test, salt‐spray test, precracked cantilever model slab test, alternate wetting and drying test and macrocell corrosion test, have been compared with uncoated rebars. It is shown that for a passivating type of coating such as cement slurry, accelerated corrosion tests could be equally valid.

Substitution of zinc chromate or zinc yellow, traditionally used as anticorrosive pigment, for other phosphate‐based pigments that are not hazardous to health and have the same anticorrosive behaviour or even better, is studied in this paper. Four alkyd paints were specially prepared; two of them contained calcium acid phosphate or micronised zinc phosphate as anticorrosive pigments respectively. A paint containing zinc chromate was used as reference and a paint without anticorrosive pigments was used as a blank, in which the other ingredients were increased proportionally to attain the desired PVC relationship. The corrosion behaviour of low carbon steel panels coated with these paints in a 3 per cent NaCl solution was assessed by electrochemical impedance spectroscopy (EIS). In addition, other painted panels were evaluated by salt spray and humidity chamber tests. Results of all tests showed that the paint with calcium acid phosphate and especially that with micronised zinc phosphate exhibited better behaviour than paint with zinc chromate. Analysis of impedance parameters (ionic resistance and capacitance of the paint film) against immersion time allowed the paints to be ranked in the same order as that obtained with salt spray and humidity chamber tests.

Health and safety legislation has forced changes in the type of anticorrosive pigments used in paint formulations, mainly focused on their substitution with different phosphates. The zinc phosphate pigment used with different types of binders has provided contradictory experimental results. In this paper, waterborne anticorrosive paints pigmented with zinc phosphates were studied. The main variables considered were PVC and the anticorrosive pigment content. Accelerated tests (salt spray, humidity chamber, and electrochemical tests) were performed to evaluate the paints’ anticorrosive performance. Good correlation was found using salt spray and impedance tests. From analysis of the time dependence of all the experimental results it was concluded that an efficient steel protection could be obtained using a waterborne epoxy primer pigmented with zinc phosphate. Such protection is attained through the barrier effect afforded by the paint film as well as the precipitation of a pretty stable ferric phosphate layer under the intact and damaged coating areas.

The objective of this work was to examine the anticorrosive behaviour of four different epoxy coatings, which were formulated with zinc pigments and were applied on pretreated steel panels exposed to deionised/deaerated water taken from the installations of the Greek Public Electricity Company, as well as to compare the results of this study with those of a relevant, previous work. The coating's performance was assessed by the measurement of the potentiodynamic polarisation resistance, by electrochemical impedance spectroscopy and the measurement of dielectric permittivity, during the deionised/deaerated water immersion tests. Additionally, accelerated salt spray tests were performed. All types of coatings tested exhibited a high protective performance. It was concluded that the epoxy system containing zinc dust was the most effective anticorrosion coating under the conditions relevant to this study.

The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance.

Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test.

The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings.

The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

Legislation is currently the key driver in the coatings industry. Reduction of the volatile organic content (VOC) of coating systems is a main aim. This may be achieved by designing the resin and coating with water as the carrying solvent. Reduction of resin viscosity to enable high solids coatings production is another route. The design and development of legislation‐compliant paint formulations based on water‐based epoxy resin systems and high solids polyurethane topcoats is discussed. A short review and discussion of the weaknesses of traditional accelerated test methods including salt‐spray, QUV^TM and Prohesion^TM used to check coating performance is presented. Some simple reaction and degradation mechanisms are shown.