Publication detail

Characterization and Corrosion Properties of Fluoride Conversion Coating Prepared on AZ31 Magnesium Alloy

DZIKOVÁ, J. FINTOVÁ, S. KAJÁNEK, D. FLORKOVÁ, Z. WASSERBAUER, J. DOLEŽAL, P.

Original Title

Characterization and Corrosion Properties of Fluoride Conversion Coating Prepared on AZ31 Magnesium Alloy

Type

journal article in Web of Science

Language

English

Original Abstract

Wrought AZ31 magnesium alloy was used as the experimental material for fluoride conversion coating preparation in Na[BF4] molten salt. Two coating temperatures, 430 degrees C and 450 degrees C, and three coating times, 0.5, 2, and 8 h, were used for the coating preparation. A scanning electron microscope and energy-dispersive X-ray spectroscopy were used for an investigation of the surface morphology and the cross-sections of the prepared coatings including chemical composition determination. The corrosion resistance of the prepared specimens was investigated in terms of the potentiodynamic tests, electrochemical impedance spectroscopy and immersion tests in the environment of simulated body fluids at 37 +/- 2 degrees C. The increase in the coating temperature and coating time resulted in higher coatings thicknesses and better corrosion resistance. Higher coating temperature was accompanied by smaller defects uniformly distributed on the coating surface. The defects were most probably created due to the reaction of the AlxMny intermetallic phase with Na[BF4] molten salt and/or with the product of its decomposition, BF3 compound, resulting in the creation of soluble Na-3[AlF6] and AlF3 compounds, which were removed from the coating during the removal of the secondary Na[MgF3] layer. The negative influence of the AlxMny intermetallic phase was correlated to the particle size and thus the size of created defects.

Keywords

AZ31 magnesium alloy; Na[BF4]; fluoride conversion coating; corrosion

Authors

DZIKOVÁ, J.; FINTOVÁ, S.; KAJÁNEK, D.; FLORKOVÁ, Z.; WASSERBAUER, J.; DOLEŽAL, P.

Released

2. 6. 2021

Publisher

MDPI

Location

BASEL

ISBN

2079-6412

Periodical

Coatings, MDPI

Year of study

11

Number

6

State

Swiss Confederation

Pages from

1

Pages to

19

Pages count

19

URL

https://www.mdpi.com/2079-6412/11/6/675

Full text in the Digital Library

http://hdl.handle.net/11012/200951

BibTex

@article{BUT172151,
  author="Juliána {Dziková} and Stanislava {Fintová} and Daniel {Kajánek} and Zuzana {Florková} and Jaromír {Wasserbauer} and Pavel {Doležal}",
  title="Characterization and Corrosion Properties of Fluoride Conversion Coating Prepared on AZ31 Magnesium Alloy",
  journal="Coatings, MDPI",
  year="2021",
  volume="11",
  number="6",
  pages="1--19",
  doi="10.3390/coatings11060675",
  issn="2079-6412",
  url="https://www.mdpi.com/2079-6412/11/6/675"
}