Moscow Polytechnic University (Moscow Polytech), Moscow, Russia

A. A. Aksenov, Doctor of Technical Sciences, Professor, Chief Researcher of the Department “Physics”, e-mail: a_aksenov_59@mail.ru
V. V. Doroshenko, Candidate of Technical Sciences, Lead Researcher of the Department “Materials Science”, Associate Professor of the Project Activity Sector, e-mail: v.doroshenko@mail.ru
D. M. Strekalina, Candidate of Chemical Sciences, Lead Researcher of the Department “Physics”, e-mail: strekalina@misis.ru

E. V. Yakushko, Candidate of Technical Sciences, Senior Researcher of the Department “Physics”, e-mail: e.v.yakushko@mospolytech.ru

Moscow Polytechnic University (Moscow Polytech), Moscow, Russia¹ ; State Research Center of the Russian Federation JSC “NPO CNIITMASH”, Moscow, Russia²
I. V. Bardin, Candidate of Chemical Sciences, Senior Researcher of the Department “Physics”¹, Head of the Corrosion Testing Laboratory², e-mail: bardin_ilya@list.ru

The article investigates the structure of sheets made from the Al – Ca – Mn aluminum alloy system, coated using the micro-arc oxidation (MAO) method. The alloy sheets with a composition of Al – 2.5%Ca – 1.5%Mn – 0.4%Fe –0.2%Si – 0.2%Cu – 0.8%Zn were produced through hot rolling and subsequently treated in a low-alkaline alkalinesilicate electrolyte. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) methods were employed to assess the microstructure and phase composition during the study. The results revealed a high dispersion of the alloy structure with various phases present, such as Al4Ca and Al6(Mn, Fe). The sizes of the dispersed eutectic precipitates ranged from 1.5 to 5 micrometers. The thickness of the obtained MAO coatings was between 20 and 30 micrometers. The coating structure in the middle of the samples was uniform, without through porosity, although some isolated pores and cracks were observed. X-ray phase analysis indicated the presence of aluminum oxides in the coating, such as α-Al₂O₃ and η-Al₂O₃. Additionally, other alloying elements like calcium, potassium, and sodium were noted. An important aspect was that the structure of the alloy near the coating remained stable, indicating good adhesion between the aluminum matrix and the coating. The authors emphasize the need for further research to optimize processes for producing strong and wear-resistant coatings, especially for applications in Arctic conditions. This work lays the groundwork for developing new structural materials with multifunctional coatings that could be beneficial in various industries, including automotive and shipbuilding.

The work was carried out within the framework of the RNF project 23-79-00055 “Creation of scientific bases for the development of new structural materials of reduced density with protective multifunctional ceramic-like coatings for use in transport systems of the Arctic region” (coating, SEM, XRD) and at the expense of the grant named after P. L. Kapitsa of Moscow Polytechnic University, implemented within the framework of the program “Priority 2030” (melting, casting, deformation processing).

The structure study was performed using the scientific equipment of the Research Chemical and Analytical Center of SIC Kurchatov Institute.

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