Degradation of unconventional fluoride conversion coating on AZ61 magnesium alloy in SBF solution

0510544 - ÚFM 2020 RIV CH eng J - Journal Article
Fintová, Stanislava - Drábiková, J. - Hadzima, B. - Trško, L. - Březina, M. - Doležal, P. - Wasserbauer, J.
Degradation of unconventional fluoride conversion coating on AZ61 magnesium alloy in SBF solution.
Surface and Coatings Technology. Roč. 380, DEC (2019), č. článku 125012. ISSN 0257-8972
Institutional support: RVO:68081723
Keywords : AZ61 magnesium alloy * Corrosion * Fluoride conversion coating * Na[BF ] 4
OECD category: Coating and films
Impact factor: 3.784, year: 2019
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S0257897219310035?via%3Dihub

The paper offers an analysis of the corrosion process of the AZ61 magnesium alloy protected with the unconventionally prepared fluoride conversion coating using Na[BF4] salt melt. The protection of the magnesium alloy with the coating was shown to vary depending on the preparation temperature (430 and 450 °C) and coating time (0.5, 2 and 8 h). Lower coating temperature and shorter coating times offer lower protection of the material against corrosion. Similar corrosion mechanism was observed for all the damaged specimens. Migration of the species from the SBF to the substrate through the coating resulted in the coating damage due to the H2 evolution and corrosion products creation following with more pronounced corrosion attack of the substrate. However, no signs of the corrosion attack were observed when the coating was prepared at 430 °C for 8 h and at 450 °C for 2 and 8 h even after 168 h of exposure of the specimen to the simulated body fluid solution at 37 ± 2 °C.
Permanent Link: http://hdl.handle.net/11104/0301488