The formation of a surface layer during microarc oxidation of aluminum alloys

17th International Scientific Conference "RESHETNEV READINGS"

Mikheev, A. Ye.^1 ; Girn, A.V.^1 ; Vakhteev, E.V.^1 ; Alekseeva, E.G.^1 ; Ravodina, D.V.^1

Siberian State Aerospace University Named after Academician M.F. Reshetnev, 31 KrasnoyarskiyRabochiy prospect, Krasnoyarsk

660014, Russia^1

关键词: Aluminium oxide;    Barrier layers;    Coating layer;    Different distributions;    Microarc oxidation;    Oxide coating;    Surface layers;    Thermochemical transformations;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/70/1/012002/pdf
DOI  :  10.1088/1757-899X/70/1/012002

来源: IOP

【 摘 要 】

The formation of a surface layer during microarc oxidation has been investigated. The results of experimental studies aimed at determining the structure and composition of oxide coatings on aluminum alloys are presented. The studies found out that, in contrast to existing ideas about the initial stages of micro-arc oxidation, a "barrier layer" grows unevenly over the sample area and there is no clear boundary between a pre-spark and a spark mode of the process. Uneven growth of a " barrier layer " is connected with different distribution of electric field on the surface of a sample and different concentration of electrolyte components. Depending on the electrolytes used the inside coating layers consist mainly of aluminium oxide, and the outer layers contain components formed as a result of thermochemical transformation of the electrolyte.