Surface Films on Zinc-Plated Steel Formed on Holding in Aqueous Extracts of Anticorrosion Pigments

The methods of X-ray photoelectron spectroscopy and Auger spectroscopy are used to study surface films formed on zinc and zinc-plated steel in the process of holding in aqueous extracts of mixtures of phosphate and calcium-containing pigments. It is shown that protective films formed mainly of zinc and calcium phosphates of different chemical structure are deposited in inhibited solutions on specimens of pure zinc and zinc-plated steel. The protective properties of these films are much better than the protective properties of the surface layers formed on the metal in the extracts of a single phosphate (or calcium-containing) pigment. The mixture of these pigments may serve as a promising substitution of chromate inhibitors in anticorrosive organic coatings.     

Corrosion of Galvanized Steel with Damaged Epoxy Coatings

We studied the corrosion behavior of galvanized steel with damaged epoxy and epoxy chromate coatings in a slightly acidic medium by the scanning reference electrode technique. We showed that corrosion fracture of a metal in the defect area occurs with separation of specific electrode reactions, and the center of anodic activity moves along the defect during the test. The potential gradient in the defect area decreases about 6 times upon introduction of chromate pigment into the epoxy primer.     

Influence of Surface-Modified Conducting Fillers on the Properties of Epoxy Coatings

We have developed a new epoxy composition for antistatic coatings on metallic surfaces, filled with technical carbon and talc, which had been surface-modified by paranitroaniline and phosphoric acid. It has been shown that, with the introduction of modified fillers, the content of gel fraction in an epoxy coating increases by 5–6%, its adhesion becomes 2.5–2.7 times higher, and the amount of organic solvents decreases. We have also established that the electric resistance of the coating is more stable in time as compared with the commercial antistatic ground-coat enamel, and the frequency dependence of the resistance is more clearly pronounced after exposure to a chloride-containing medium, which corroborates the better protective properties of antistatic coatings with modified current conductive fillers. __________ Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 41, No. 4, pp. 53–58, July–August, 2005.     

Effect of polystyrol coatings on the corrosion fatigue resistance of 09G2S steel in sea water

Translated from Fiziko-khimicheskaya Mekhanika Materialov, No. 5, pp. 114–115, September–October, 1990.     

The effect of chromate pigment on the protective properties of an epoxy prime coat

Conclusions The protective function of strontium chromate pigment in the epoxy prime coat on the galvanized steel is manifested simultaneously with penetration of the corrosive medium to the metal surface and consists of an increase (by an order of magnitude) in polarization resistance and inhibition of corrosion of the galvanized steel at the places of through defects of the polymer coating. Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 35, No. 5, pp. 111–113, September–October, 1999.     

Corrosion-fatigue endurance of 09G2S steel with an allowance made for cathodic protection

Translated from Fiziko-Khimicheskaya Mekhanika Matrialov, Vol. 25, No. 3, pp. 101–102, May–June, 1989.     

Effect of the modes of formation on the protective properties of conversion-polymeric coatings

We study regularities of changes in the total electrode potential, de resistance, and impedance of lowcarbon steel with conversion-polymeric coatings as functions of the temperature and time conditions of their formation and of the time of holding in corrosive media. We establish the relationship between electrochemical corrosion processes in metal covered with conversion-polymeric coatings and the barrier-adhesion mechanism of the protective action of coatings. We establish the following optimal mode of the application of coatings of modified SKD-1s latex: polymerization for 110–130 sec at a temperature of 220–240°C. Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. State University of Chemical Engineering, Dnepropetrovsk. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 32, No. 5, pp. 50–54, September–October, 1996.     

Properties of epoxy-amine coatings modified with petroleum polymeric resins

We study the composition of the gel fraction, water absorption, and impedance characteristics of epoxy coatings modified with petroleum polymeric resin treated with maleic anhydride. It is shown that modified epoxy coatings are characterized by higher water resistance and better protective properties in acid media. We determine the optimal amount of the petroleum polymeric modifier and demonstrate the possibility of improvement of the corrosion resistance of modified epoxy coatings by subsequent thermal treatment. Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 32, No. 4, pp. 81–85, July–August, 1996.     

Synergistic Effect of Phosphate and Calcium-Containing Pigments on the Corrosion Resistance of Galvanized Steel

We studied the corrosion inhibition of galvanized steel in artificial acid rain solution by chromate-free pigments containing phosphate and calcium ions. We used the methods of electrochemical impedance spectroscopy, potentiodynamic polarization, electron microscopy, and X-ray microspectrum analysis. It was established that the combination of modified zinc phosphate and ion-exchange-type calcium-containing pigment provides a significant synergistic anticorrosion effect on galvanized steel as compared with the same inhibiting pigments used separately. The charge-transfer resistance of the metal in acid rain solution saturated with this pigment composition approaches that in the same solution with a chromate inhibitor and is significantly higher as compared with the solutions of separate pigments. Owing to the combination of nonchromate pigments, a protective film is formed on galvanized steel, which represents a complex mixture of calcium and zinc phosphates and guarantees the corrosion inhibition of galvanized steel under mixed cathodic-anodic control.