Publication detail

Structure and growth kinetic of unconventional fluoride conversion coating prepared on wrought AZ61 magnesium alloy

DRÁBIKOVÁ, J. FINTOVÁ, S. PTÁČEK, P. KUBĚNA, I. BŘEZINA, M. WASSERBAUER, J. DOLEŽAL, P. PASTOREK, F.

Original Title

Structure and growth kinetic of unconventional fluoride conversion coating prepared on wrought AZ61 magnesium alloy

Type

journal article in Web of Science

Language

English

Original Abstract

The structure, kinetics and thermodynamics of formation of unconventional fluoride conversion coating on wrought AZ61 magnesium alloy are described in this work. Fluoride conversion coating was prepared by immersion of the specimens of AZ61 magnesium alloy into Na[BF4] molten salt at 410, 420, 430, 440 and 450 degrees C for 0.5, 1, 2, 4, 8, 12, 24 and 36 h. Testing methods, such as scanning electron microscopy, focused ion beam cutting and transmission electron microscopy were used for the morphology analysis, chemical composition and microstructure investigation of the fluoride conversion coating. It was found that the coating was composed of the primary MgF2 and secondary Na[MgF3] layer. The growth mechanism of the primary coating layer was described by the empirical kinetic method. The apparent activation energy and pre-exponential factor, estimated from the Arrhenius plot, are 82.87 kJ.mol(-1) and 8.22 s(-1), respectively. The kinetic analysis of the coating growth indicates that the process is driven by the parabolic rate law of the stationary one-dimensional diffusion at 410 degrees C. The Jander equation of the stationary three-dimensional diffusion describes the coating growth at higher investigated temperatures.

Keywords

Magnesium alloys; Coating; Kinetic; Diffusion

Authors

DRÁBIKOVÁ, J.; FINTOVÁ, S.; PTÁČEK, P.; KUBĚNA, I.; BŘEZINA, M.; WASSERBAUER, J.; DOLEŽAL, P.; PASTOREK, F.

Released

15. 10. 2020

Publisher

ELSEVIER SCIENCE SA

Location

LAUSANNE

ISBN

0257-8972

Periodical

Surface and Coatings Technology

Year of study

399

Number

1

State

Swiss Confederation

Pages from

1

Pages to

10

Pages count

10

URL

https://www.sciencedirect.com/science/article/abs/pii/S0257897220307702?via%3Dihub

BibTex

@article{BUT167330,
  author="Juliána {Drábiková} and Stanislava {Fintová} and Petr {Ptáček} and Ivo {Kuběna} and Matěj {Březina} and Jaromír {Wasserbauer} and Pavel {Doležal} and Filip {Pastorek}",
  title="Structure and growth kinetic of unconventional fluoride conversion coating prepared on wrought AZ61 magnesium alloy",
  journal="Surface and Coatings Technology",
  year="2020",
  volume="399",
  number="1",
  pages="1--10",
  doi="10.1016/j.surfcoat.2020.126101",
  issn="0257-8972",
  url="https://www.sciencedirect.com/science/article/abs/pii/S0257897220307702?via%3Dihub"
}