TY - JOUR
T1 - LDH conversion films for active protection of AZ31 Mg alloy
AU - Pillado, Borja
AU - Mingo, Beatriz
AU - del Olmo, Ruben
AU - Endzhe, Matykina
AU - Kooijman, A.M
AU - Gonzalez-Garcia, Yaiza
AU - Arrabal, Raul
AU - Mohedano, Marta
N1 - Funding Information:
The authors gratefully acknowledge the support of the RTI2018-096391-B-C33 FEDER/ Ministerio de Ciencia e Innovación−Agencia Estatal de Investigación, S2018/NMT−4411 Regional Government of Madrid and EU Structural and Social Funds and PID2021-124341OB-C22 (MCIU/AEI/FEDER, UE). M. Mohedano is grateful for the support of RYC-2017 21843, Ministerio de Ciencia e Innovación. B. Mingo is supported by the Royal Academy of Engineering through the RAEng Research Fellowship and by EPSRC (EP/V026097/1)
Publisher Copyright:
© 2022
PY - 2022/10/5
Y1 - 2022/10/5
N2 - Zinc aluminium (Zn-Al) and lithium aluminium (Li-Al) – layered double hydroxides (LDH) coatings with incorporated inhibitors (Li−, Mo− and W−based) were successfully synthesized on AZ31 Mg alloy. Zn−Al LDH W and Li−Al LDH Li showed the highest corrosion resistance and were selected for further evaluation. SEM cross−section examination revealed a bi−layer structure composed of an outer part with loose flakes and a denser inner layer. XRD, FTIR, and XPS analysis confirmed the incorporation of the inhibitors. Post−treatments with corrosion inhibitors containing solutions resulted in the selective dissolution of the most external layer of the LDH coating, reducing the surface roughness, hydrophilicity and paint adhesion of the layers. Active corrosion properties were confirmed by SVET evaluation for the Zn−Al LDH W coating. The proposed active corrosion mechanism involves the ion−exchange of aggressive Cl− ions, deposition of hydroxides and competitive adsorption of W−rich corrosion inhibitors.
AB - Zinc aluminium (Zn-Al) and lithium aluminium (Li-Al) – layered double hydroxides (LDH) coatings with incorporated inhibitors (Li−, Mo− and W−based) were successfully synthesized on AZ31 Mg alloy. Zn−Al LDH W and Li−Al LDH Li showed the highest corrosion resistance and were selected for further evaluation. SEM cross−section examination revealed a bi−layer structure composed of an outer part with loose flakes and a denser inner layer. XRD, FTIR, and XPS analysis confirmed the incorporation of the inhibitors. Post−treatments with corrosion inhibitors containing solutions resulted in the selective dissolution of the most external layer of the LDH coating, reducing the surface roughness, hydrophilicity and paint adhesion of the layers. Active corrosion properties were confirmed by SVET evaluation for the Zn−Al LDH W coating. The proposed active corrosion mechanism involves the ion−exchange of aggressive Cl− ions, deposition of hydroxides and competitive adsorption of W−rich corrosion inhibitors.
KW - AZ31
KW - Active corrosion protection
KW - Corrosion inhibitors
KW - Layered double hydroxides
KW - Magnesium
UR - https://www.scopus.com/pages/publications/85140223038
U2 - 10.1016/j.jma.2022.09.014
DO - 10.1016/j.jma.2022.09.014
M3 - Article
SN - 2213-9567
JO - Journal of Magnesium and Alloys
JF - Journal of Magnesium and Alloys
ER -