Mixed alumina and cobalt containing plasma electrolytic oxide coatings

2017 Global Conference on Polymer and Composite Materials

材料科学;化学

Yar-Mukhamedova, G.Sh.^1 ; Ved, M.V.^2 ; Karakurkchi, A.V.^2 ; Sakhnenko, N.D.^2

Physics Department, Al-Farabi Kazakh National University, IETP, 71 Al-Farabi avenue, Kazakhstan^1

Physical Chemistry Department, National Technical University, Kharkiv Polytechnic Institute, 2 Kyrpychova Street, Kharkiv

61002, Ukraine^2

关键词: Catalytic properties;    Cobalt oxides;    Electrolysis current;    Mixed oxide systems;    Plasma electrolytic oxidation;    Plasma electrolytic oxide coatings;    Synthesized materials;    Thermo-Chemical reactions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/213/1/012020/pdf
DOI  :  10.1088/1757-899X/213/1/012020

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Principles of plasma electrolytic oxidation of the AL25 aluminum alloy in diphosphate alkali solutions containing cobalt(2+) cations are discussed. It has been established that a variation in the concentration of the electrolyte components provides the formation of mixed-oxide coatings consisting of the basic matrix materials and the cobalt oxides of different content. An increase in the cobalt oxide content in the coating is achieved by the variation in electrolysis current density as well as the treatment time due to both the electrochemical and thermo-chemical reactions at substrate surface and in spark region. Current density intervals that provide micro-globular surface formation and uniform cobalt distribution in the coating are determined. The composition and morphology of the surface causes high catalytic properties of synthesized materials, which confirmed the results of testing in model reaction CO and benzene oxidation as well as fuel combustion for various modes of engine operation.