Structure and Protective Properties of Complex Chromosilicide Diffusion Coatings on Steel 20

Authors I. Pohrebova1, K. Yantsevych2, T. Loskutova1, N. Kharchenko3 , T. Hоvоrun3

1National Technical University of Ukraine “I. Sikorsky Kyiv Polytechnic Institute”, 37, Beresteiskyi ave, 03056, Kyiv, Ukraine

2E.O. Paton Electric Welding Institute, 11, Kazymyr Malevych st., 03150 Kyiv, Ukraine

3Sumy State University, 2, Rimsky Korsakov st., 40007 Sumy, Ukraine

Issue Volume 15, Year 2023, Number 5
Dates Received 05 August 2023; revised manuscript received 18 October 2023; published online 30 October 2023
Citation I. Pohrebova, K. Yantsevych, T. Loskutova, et al., J. Nano- Electron. Phys. 15 No 5, 05031 (2023)
PACS Number(s) 61.46. – w, 62.20.Qp, 62.20. – х, 68.55N
Keywords Diffusion coatings, Microhardness (2) , Chromosiliconizing.

The paper presents the results of studies of the structure, chemical composition, microhardness, heat, and corrosion resistance of multicomponent coatings obtained during diffusion chromosiliconizing of steel 20. The coating was applied in a specially designed reaction chamber at a temperature of 1050 ºС for 6 hours to the surface of carbon steel 20 in a closed reaction space at a reduced pressure of the active gas phase, for the formation of which rational amounts of silicon and chromium were used, as well as carbon tetrachloride as an activator. It was established that the obtained coatings consist of carbides of chromium Cr23C6, Cr7C3 doped with silicon and a zone of solid solution of chromium and silicon in iron. The maximum amount of silicon is observed in the inner area of the coating (2.82 – 3.89 wt. %) at a depth of 15-50 microns. The total thickness of the coating is 110 μm, and the microhardness of the surface layers is 19.5 GPa. The surface layers of coatings, based on chromium and silicon, lead to the formation of protective films Cr2O3, Al2O3, which ensures their high heat resistance in the air atmosphere and corrosion resistance in oxidizing acids. The possibility of increasing the corrosion resistance of coatings by introducing inorganic oxidants into aggressive solutions has been established.

List of References