Active corrosion protection coating for a ZE41 magnesium alloy created by combining PEO and sol-gel techniques
By Ivanou, D. K. and Yasakau, K. A. and Kallip, S. and Lisenkov, A. D. and Starykevich, M. and Lamaka, S. V. and Ferreira, M. G. S. and Zheludkevich, M. L.
Published in RSC Adv.
The Royal Society of Chemistry
2016
Abstract
An active protective coating for ZE41 magnesium alloy was produced by sealing an anodic layer, loaded with 1,2,4-triazole, with a sol-gel film. An anodic oxide layer was formed using PEO in a silicate-fluoride alkaline solution. This thin (1.8 [small mu ]m) porous PEO layer was impregnated with corrosion inhibitor 1,2,4-triazole and sealed with a silica-based sol-gel film modified with titanium oxide. For the first time it was demonstrated that this relatively thin PEO-based composite coating revealed high barrier properties and provided superior protection against corrosion attack during 1 month of continuous exposure to 3% NaCl. A scanning vibrating electrode technique showed a sharp decrease (100 times) of corrosion activity in micro defects formed in the 1,2,4-triazole doped composite coating, when compared to blank samples.