Machines. Technologies. Materials.
Vol. 14 (2020), Issue 6, pg(s) 247-250

MATERIALS

Structure and properties of microarc oxide coatings on high-temperature aluminum alloy

  • 1 National Technical University «Kharkiv Polytechnic Institute», Kharkiv, Ukraine

Abstract

To create a high-hardness and wear-resistant coating on the heat-resistant aluminum AK4 alloy, the technology of microarc oxidation is used. The possibility of forming an oxide layer on the surface (mainly of α−Al2O3 and γ−Al2O3 phases) with a thickness of about 150 μm and a hardness of 17000 – 18000 MPa is shown. For this, the process of microarc oxidation was carried out at a current density of 20 A/dm2 in an electrolyte of the composition KOH (1-2 g/L) and Na2SiO3 (6-12 g/L). The obtained properties of MAO coatings on the AK4 alloy make it possible to effectively use such materials for engine elements.

Keywords

References

  1. Li H. X., Li W. J., Song R. G., Ji Z. Effects of different current densities on properties of MAO coatings embedded with and without -Al2O3 nanoadditives. Mater. Sci. Technol., 2012, vol. 28, pp. 565-568.
  2. Veys-Renaux D., Rocca E., Henrion G. Micro-arc oxidation of AZ91 Mg alloy: An in-situ electrochemical study. Electrochem. Commun., 2013, vol. 31, pp. 42-45.
  3. He Q., Freakley S.J., Edwards J.K., Carley A.F., Borisevich A.Y., Mineo Y., Haruta M., Hutchings G.J., Kiely C.J. Population and hierarchy of active species in gold iron oxide catalysts for carbon monoxide oxidation. Nat Commun., 2016, vol.7, p. 12905.
  4. Martin J., Leone P., Nomine A., Veys-Renaux D., Henrion G., Belmonte T. Influence of electrolyte ageing on the plasma electrolytic oxidation of aluminium. Surf Coat Technol., 2015. Vol.269, pp. 36–46.
  5. Belozerov V., Mahatilova A., Sobol' O., Subbotina V., Subbotin A. Investigation of the influence of technological conditions of microarc oxidation of magnesium alloys on their structural state and mechanical properties. EasternEuropean Journal of Enterprise Technologies, 2017, vol. 2, n. 5(86), pp. 39- 43.
  6. Subbotina V., Al-Qawabeha U.F., Belozerov V., Sobol’ O.V., Subbotin A., Tabaza T.A., Al-Qawabah S.M. Determination of influence of electrolyte composition and impurities on the content of α-Al2O3 phase in mao-coatings on aluminum, Eastern-European Journal of Enterprise Technologies, 2019, vol. 6, n.12(102), pp. 6- 13.
  7. Belozerov V., Sobol’ O., Mahatilova A., Subbotina V., Tabaza T. A., Al-Qawabeha U. F., Al-Qawabah S. M. Effect of electrolysis regimes on the structure and properties of coatings on aluminum alloys formed by anode-cathode micro arc oxidation Eastern-European Journal of Enterprise Technologies, 2018, vpl. 1, n.12(91), pp. 43-47.
  8. Klopotov A. A., Abzaev Yu. A., Potekaev A. I., Volokitin O. G. Osnovi rentgenostrukturnogo analiza v materialovedenii. Tomsk: Izd-vo Tom. gos. arhit.-stroit. Un-ta, 2012, 276 p

Article full text

Download PDF