European Federation of Corrosion National Academy of Sciences of Ukraine Ministry of Education and Science of Ukraine Ukrainian Association of Corrosionists Karpenko Physico-Mechanical Institute Ivan Franko Lviv National University Ivano-Frankivsk National Technical University of Oil and Gas ХV International Conference «Problems of corrosion and corrosion protection of materials» (Corrosion-2020) (461 event of the European Federation of Corrosion) ABSTRACT BOOK October 15–16, 2020 Lviv, Ukraine UДC 539.3, 620.193, 620.194, 620.179, 620.197, 621.181:669.018, 621.785. XV International Conference “Problems of Corrosion and Corrosion Protection of Materials“ (Corrosion-2020). October 15-16, 2020, Lviv, Ukraine: Book of Abstract / Karpenko Physico-Mechanical Institute of NAS of Ukraine; S. Korniy, М.-О. Danyliak, Yu. Maksishko (Eds.). – Lviv, 2020. – 121 p. XV International Conference “Problems of Corrosion and Corrosion Protection of Materials“ (Corrosion-2020) was held at Lviv Palace of Arts on October 15-16, 2020. This Book of Abstract contains the results of studies are devoted to fundamentals of corrosion and corrosion assisted mechanical fracture; hydrogen and gas corrosion; new corrosion resistant materials; thermal spray, electroplated and other coatings; inhibitor, biocidal and electrochemical protection; testing methods and corrosion control; corrosion protection of oil and gas industry and chemical equipment. In the authors edition. Editorial board: S. Korniy, М.-О. Danyliak, Yu. Maksishko ©Karpenko Physico-Mechanical Institute of NAS of Ukraine, Lviv, 2020 CONFERENCE TOPICS: fundamentals of corrosion and corrosion assisted mechanical fracture; hydrogen and gas corrosion; new corrosion resistant materials and coatings; inhibitor and biocidal protection; electrochemical protection; testing methods and corrosion control; corrosion protected equipment of the oil and gas, chemical and energy industries. PROGRAMME COMMITTEE: V. Pokhmurskii (Ukraine) – Chairman M. Khoma (Ukraine) – Vice-Chairman R. Baessler (Germany), F. Danilov (Ukraine), I. Dmytrakh (Ukraine), I. Zin (Ukraine), L. Kwiatkowski (Poland), V. Korolev (Ukraine), Ye. Kryzhanivskyi (Ukraine), A. Krolikowska (Poland), V. Kublanovskyi (Ukraine), О. Kuntyi (Ukraine), S. Lyon (UK), Th. Lampke (Germany), O. Liniucheva (Ukraine), E. Lunarska (Poland), Z. Nazarchuk (Ukraine), H. Nykyforchyn (Ukraine), O. Reshetnyak (Ukraine), M. Sakhnenko (Ukraine), М. Ferreira (Portugal), J. Fernandes (Portugal), J. Chen (China), O. Chygyrynets (Ukraine), G. Schmitt (Germany), G. Yar-Mukhamedova (Kazakhstan) ORGANIZING COMMITTEE: S. Korniy – Chairman V. Vynar – Vice-Chairman L. Boichyshyn, Kh. Vasyliv, М. Ved, І. Vynar, R. Dzhala, О. Zvirko, О. Narivskiy, L. Nyrkova, І. Pohrelyuk, H. Pokhmurska, A. Syrotyuk, L. Frankevych, V. Chervatyuk, О. Yaskiv CONFERENCE SECRETARIAT: М.-О. Danyliak О. Khlopyk Yu. Maksishko E-mail: [email protected] [email protected] Web site: http://www.ipm.lviv.ua/corrosion2020/ Conference “Problems of Corrosion and Corrosion Protection of Materials“ (Corrosion-2020) is supported by Lviv Oblast Council SPC Halychyna SEC “Teсhno-Resurs” SE Gazotermic LLC “Technology Center to protect metals from corrosion” Fundamentals of corrosion and corrosion assisted mechanical fracture 1 Hydrogen and gas corrosion INFLUENCE OF CHROMIUM SALTS ON CORROSION OF INCOLOY 800 H/HT ALLOY IN FLUORIDE EUTECTIC MELT FLINAK Pavlik V., Boca M. Institute of Inorganic Chemistry, Slovak Academy of Sciences, Slovak Republic [email protected] The effect of three chromium salts – potential impurities was analysed with the assumed effect of increasing the corrosion efficiency of eutectic mixture FLINAK on model alloy Incoloy 800H/HT. The occurrence of similar mixtures using superalloys is predicted in the future for 4th generation molten salts nuclear reactors and have been studied by various authors from different perspectives [1, 2, 3]. Salts containing bound chromium, oxygen, fluorine and water (namely CrF3.3H2O, CrF3 and Cr2O3) were used to observe their corrosiveness through dependence on the weight loss of the samples. One of the main ideas of this work was search for corrosion suppressor that could be added into the system to reverse or slow down overall corrosion process. Experiments consisted of static tests, with samples (diameter 12 mm, thickness 1.2 mm) placed in prepared mixtures (25 g) with different salt concentrations (x = 0, 0.5, 1, 3, 5 mol %). A glove-box furnace with an argon atmosphere was used. The SEM analyses of the surfaces shown corrosion attack on all samples. The surfaces of the samples, which was exposed to concentrations of more than 1 mol % of hydrated CrF3 appeared to be most damaged with comparison against all other FLINAK mixtures. The SEM-EDX cross-sections shown dealloying of the elements from surfaces, mainly chromium and iron, which is in agreement with general corrosion theory. The process of forming corrosion products was demonstrated by WD-XRF complementary analysis of the mixtures after corrosion. The higher chromium and iron content in the mixtures meant a higher weight loss of material. Gravimetric analysis shown strong dependence of weight changes on concentration of added salts. It has been found that there is always a different corrosion resistance of the material depending on the concentration of cation and / or anion present in the corrosion mixture. The corrosion rate of the material with acidic or hydrated salts is several times higher than that of oxides. It is assumed that the main corrosion mechanism involves the formation of gaseous HF, which preferably reacts with the alloying element to form more volatile or soluble corrosion product depending on Gibbs formation enthalpy. In the case of addition of oxides to molten mixture, this may be a factor that may help to suppress the corrosion reaction when it’s detected in power plant's rapid protection system in the future. 1. V. Pavlik, M. Kontrik, M. Boca Corrosion behaviour of Incoloz 800H/HT in the fluoride molten salt Flinak + MFx (MFx = CrF3, FeF2, FeF3 and NiF2) // New J.Chem. – 2015. – Vol. 39. – P. 9841–9847. 2. N.S. Patel, V. Pavlik, M. Boca High-Temperature Corrosion Behavior of Superalloys in Molten Salts – A Review // Crit. Rev. Solid State Mater. Sci. – 2017. – Vol. 42. No. 1. – P. 83–97. 3. V. Pavlik, P. Barborik, M. Boca, Z. Vaskova Interaction of metallic zirconium and its alloys Zry-2 and E110 with molten eutectic salt of LiF-NaF-KF containing zirconium fluoride components // Chem. Pap. – 2016. – Vol. 70. – Iss. 2 – P. 197–205. 2 CORROSION-2020 CORROSION RESISTANCE OF [(Zn-Ni)1/(Zn-Ni)2]n COATINGS IN COMPARISON WITH Zn-Ni ALLOY COATINGS Maizelis A., Bairachnyi B. National Technical University “Kharkiv Polytechnic Institute” [email protected] Multilayer coatings consisting of periodically alternating layers of different compositions with a thickness of about 100 nm each and obtained by various physical methods show improved functional properties both as compared with corresponding alloys and metal coatings. The opportunity to improve the performance of coatings solves the urgent task of resource saving in many industries. Electrochemical methods of metals and alloys deposition have advantages associated with the use of simpler equipment and the ability to treat parts of various shapes and sizes. The zinc-nickel alloy used to protect steel parts from corrosion [1-3] is an example of the influence of both chemical and phase composition on the properties of the resulting coatings, including their protective properties. Zinc-nickel alloy coatings were deposited from a pyrophosphate-citrate electrolyte on low-carbon steel samples in the galvanostatic mode. Multilayer coatings consisting of layers of alloys of different chemical and phase compositions were deposited using a two-pulse galvanostatic method. The corrosion behavior of samples with multilayer coatings was compared with alloy coatings of the same thickness and having nickel content corresponding to both the average nickel content in multilayer coatings and composition of the sublayers of multilayer coatings. After exposure in 0.5 mol L-1 NaCl solution for half an hour, the corrosion potentials of multilayer coatings with average nickel content in the range of 9.8-22.3% practically do not differ from the corrosion potentials of freshly deposited Zn-Ni alloy coatings with the same nickel content. Long-term monitoring of the stationary potentials of coated samples, with periodic updating of the NaCl solution, reveals significant differences in the kinetics of corrosion dissolution of the coatings. As zinc dissolves from the coating, the potentials of all coatings increased with time shifting to the potential of the steel substrate, after which the sacrificial protection nature of the coating ends. The shape of this dependence is practically same in the case of multilayer and single-layer coatings containing 9.8% nickel. The time until the potential of the steel base reaches in both cases did not exceed a week. Coatings with nickel content close to the composition of γ-phase reached the potential of the steel substrate in 8 days, while it took about 20 days for multilayer coatings. Both single-layer and multilayer coatings with excess nickel content with respect to the γ-phase remained sacrificial for 38 and 67 days, respectively. 1. A. Tozar, I.H. Karahan Structural and corrosion protection properties of electrochemically deposited nano- sized Zn–Ni alloy coatings // Appl. Surf. Sci. – 2014.