1. Corrosion Laboratory for Light Metals, College of Materials Science and Engineering, Shandong University of Science and Technology, Qingdao 266590, China 2. School of Materials Science and Engineering, Liaocheng University, Liaocheng 252059, China
A hydrophobic surface was successfully fabricated on the Mg–Al-layered double hydroxide (Mg–Al LDH)/Mg(OH)2-coated AZ31 magnesium alloy via an in-situ steam coating (SC) process and a subsequent surface modification with environment-friendly myristic acid (MA). The microstructure, composition and hydrophobicity of SC/MA composite coating were investigated by XRD, SEM, EDS, FTIR, and contact angle (CA) measurement. The corrosion behavior of the hybrid coating was evaluated by potentiodynamic polarization, EIS and hydrogen evolution test in 3.5 wt.% NaCl solution. The results showed that the LDH coating had nano-flake microstructure, which remained unchanged after modification with MA. The CA of the MA-modified coating surface reached up to 129°±3.5°, and the corrosion current density of SC/MA-2 coating decreased about three orders of the magnitude compared to that of the substrate. It is proven that the modified surface has an effective anti-corrosion effect on AZ31 alloy. The formation mechanism and the corrosion mechanism of the coating were also discussed.
P Jia, M Wu, J Zhang, et al.. Effects of Mg‒Zn‒Y quasicrystal addition on the microstructures, mechanical performances and corrosion behaviors of as-cast AM60 magnesium alloy. Materials Research Express, 2018, 5(10): 106512 doi:10.1088/2053-1591/aada70
2
F S Pan, B Zeng, B Jiang, et al.. Enhanced mechanical properties of AZ31B magnesium alloy thin sheets processed by on-line heating rolling. Journal of Alloys and Compounds, 2017, 693: 414–420 https://doi.org/10.1016/j.jallcom.2016.09.220
3
F Li, Y Liu, X B Li. Dynamic recrystallization behavior of AZ31 magnesium alloy processed by alternate forward extrusion. Frontiers of Materials Science, 2017, 11(3): 296–305 https://doi.org/10.1007/s11706-017-0387-7
4
T Jin, Y Wang, H Yin, et al.. Corrosion protection properties and mechanism of epoxy/acetic acid-doped polyaniline coating on magnesium alloy. Journal of Nanoscience and Nanotechnology, 2018, 18(7): 4992–5000 https://doi.org/10.1166/jnn.2018.15278
pmid: 29442684
5
H Jin, X Yang, M Wang. Chemical conversion coating on AZ31B magnesium alloy and its corrosion tendency. Acta Metallurgica Sinica (English Letters), 2009, 22(1): 65–70 https://doi.org/10.1016/S1006-7191(08)60072-1
6
T Ishizaki, R Kudo, T Omi, et al.. Magnesium hydroxide/magnesium phosphate compounds composite coating for corrosion protection of magnesium alloy by a combination process of chemical conversion and steam curing. Materials Letters, 2012, 68: 122–125 https://doi.org/10.1016/j.matlet.2011.10.045
7
F Zhang, C L Zhang, L Song, et al.. Corrosion resistance of superhydrophobic Mg‒Al layered double hydroxide coatings on aluminum alloys. Acta Metallurgica Sinica (English Letters), 2015, 28(11): 1373–1381 doi:10.1007/s40195-015-0335-4
8
C Y Li, X L Fan, R C Zeng, et al.. Corrosion resistance of in-situ growth of nano-sized Mg(OH)2 on micro-arc oxidized magnesium alloy AZ31 — Influence of EDTA. Journal of Materials Science and Technology, 2019, 35(6): 1088–1098 https://doi.org/10.1016/j.jmst.2019.01.006
9
B P Singh, B K Jena, S Bhattacharjee, et al.. Development of oxidation and corrosion resistance hydrophobic graphene oxide‒polymer composite coating on copper. Surface and Coatings Technology, 2013, 232: 475–481 https://doi.org/10.1016/j.surfcoat.2013.06.004
10
R C Zeng, W C Qi, Y W Song, et al.. In vitro degradation of MAO/PLA coating on Mg‒1.21Li‒1.12Ca‒1.0Y alloy. Frontiers of Materials Science, 2014, 8(4): 343–353 https://doi.org/10.1007/s11706-014-0264-6
11
T Jin, Y Han, R Bai, et al.. Corrosion protection properties of nano NH2-reduced graphene oxide/epoxy composite coatings formed by self-curing on magnesium alloy. Journal of Nanoscience and Nanotechnology, 2018, 18(7): 4971–4981 https://doi.org/10.1166/jnn.2018.15357
pmid: 29442681
12
J Liang, R H Zhang, Z J Peng, et al.. One-step electrochemical fabrication of bilayered MgO/polymer coating on magnesium alloy. Frontiers of Materials Science, 2014, 8(3): 307–312 https://doi.org/10.1007/s11706-014-0250-z
13
T Jin, F M Kong, R Q Bai, et al.. Anti-corrosion mechanism of epoxy-resin and different content Fe2O3 coatings on magnesium alloy. Frontiers of Materials Science, 2016, 10(4): 367–374 https://doi.org/10.1007/s11706-016-0357-5
14
L Y Li, L Y Cui, R C Zeng, et al.. Advances in functionalized polymer coatings on biodegradable magnesium alloys — A review. Acta Biomaterialia, 2018, 79: 23–36 https://doi.org/10.1016/j.actbio.2018.08.030
pmid: 30149212
15
G Zhang, L Wu, A T Tang, et al.. Growth behavior of MgAl-layered double hydroxide films by conversion of anodic films on magnesium alloy AZ31 and their corrosion protection. Applied Surface Science, 2018, 456: 419–429 https://doi.org/10.1016/j.apsusc.2018.06.085
16
L Wu, D N Yang, G Zhang, et al.. Fabrication and characterization of Mg‒M layered double hydroxide films on anodized magnesium alloy AZ31. Applied Surface Science, 2018, 431: 177–186 https://doi.org/10.1016/j.apsusc.2017.06.244
17
G Zhang, L Wu, A T Tang, et al.. Active corrosion protection by a smart coating based on a MgAl-layered double hydroxide on a cerium-modified plasma electrolytic oxidation coating on Mg alloy AZ31. Corrosion Science, 2018, 139: 370–382 https://doi.org/10.1016/j.corsci.2018.05.010
18
T Ishizaki, N Kamiyama, K Watanabe, et al.. Corrosion resistance of Mg(OH)2/Mg‒Al layered double hydroxide composite film formed directly on combustion-resistant magnesium alloy AMCa602 by steam coating. Corrosion Science, 2015, 92: 76–84 https://doi.org/10.1016/j.corsci.2014.11.031
19
L Guo, F Zhang, J C Lu, et al.. A comparison of corrosion inhibition of magnesium aluminum and zinc aluminum vanadate intercalated layered double hydroxides on magnesium alloys. Frontiers of Materials Science, 2018, 12(2): 198–206 https://doi.org/10.1007/s11706-018-0415-2
20
J Chen, Y W Song, D Y Shan, et al.. Study of the in situ growth mechanism of Mg‒Al hydrotalcite conversion film on AZ31 magnesium alloy. Corrosion Science, 2012, 63: 148–158 https://doi.org/10.1016/j.corsci.2012.05.022
21
J Chen, Y Song, D Shan, et al.. Study of the corrosion mechanism of the in situ grown Mg–Al–CO32− hydrotalcite film on AZ31 alloy. Corrosion Science, 2012, 65: 268–277 https://doi.org/10.1016/j.corsci.2012.08.026
22
R C Zeng, X T Li, Z G Liu, et al.. Corrosion resistance of Zn‒Al layered double hydroxide/poly(lactic acid) composite coating on magnesium alloy AZ31. Frontiers of Materials Science, 2015, 9(4): 355–365 https://doi.org/10.1007/s11706-015-0307-7
23
D D Li, F Y Wang, X Yu, et al.. Anticorrosion organic coating with layered double hydroxide loaded with corrosion inhibitor of tungstate. Progress in Organic Coatings, 2011, 71(3): 302–309 https://doi.org/10.1016/j.porgcoat.2011.03.023
24
R C Zeng, Z G Liu, F Zhang, et al.. Corrosion of molybdate intercalated hydrotalcite coating on AZ31 Mg alloy. Journal of Materials Chemistry A: Materials for Energy and Sustainability, 2014, 2(32): 13049–13057 https://doi.org/10.1039/C4TA01341G
25
Q S Yao, F Zhang, L Song, et al.. Corrosion resistance of a ceria/polymethyltrimethoxysilane modified Mg‒Al-layered double hydroxide on AZ31 magnesium alloy. Journal of Alloys and Compounds, 2018, 764: 913–928 https://doi.org/10.1016/j.jallcom.2018.06.152
26
N Kamiyama, G Panomsuwan, E Yamamoto, et al.. Effect of treatment time in the Mg(OH)2/Mg‒Al LDH composite film formed on Mg alloy AZ31 by steam coating on the corrosion resistance. Surface and Coatings Technology, 2016, 286: 172–177 https://doi.org/10.1016/j.surfcoat.2015.11.051
27
T Ishizaki, S Chiba, H Suzuki. In situ formation of anticorrosive Mg‒Al layered double hydroxide-containing magnesium hydroxide film on magnesium alloy by steam coating. ECS Electrochemistry Letters, 2013, 2(5): C15–C17 https://doi.org/10.1149/2.006305eel
28
T Ishizaki, S Chiba, K Watanabe, et al.. Corrosion resistance of Mg‒Al layered double hydroxide container-containing magnesium hydroxide films formed directly on magnesium alloy by chemical-free steam coating. Journal of Materials Chemistry A: Materials for Energy and Sustainability, 2013, 1(31): 8968–8977 https://doi.org/10.1039/c3ta11015j
29
S Huang, H Peng, W W Tjiu, et al.. Assembling exfoliated layered double hydroxide (LDH) nanosheet/carbon nanotube (CNT) hybrids via electrostatic force and fabricating nylon nanocomposites. The Journal of Physical Chemistry B, 2010, 114(50): 16766–16772 https://doi.org/10.1021/jp1087256
pmid: 21126035
30
H Liao, Y Jia, L Wang, et al.. Size effect of layered double hydroxide platelets on the crystallization behavior of isotactic polypropylene. ACS Omega, 2017, 2(8): 4253–4260 https://doi.org/10.1021/acsomega.7b00621
pmid: 31457718
31
J Zhang, C Gu, J Tu. Robust slippery coating with superior corrosion resistance and anti-icing performance for AZ31B Mg alloy protection. ACS Applied Materials & Interfaces, 2017, 9(12): 11247–11257 https://doi.org/10.1021/acsami.7b00972
pmid: 28277644
32
Z Yuan, X Wang, J Bin, et al.. Controllable fabrication of lotus-leaf-like superhydrophobic surface on copper foil by self-assembly. Applied Physics A: Materials Science & Processing, 2014, 116(4): 1613‒1620 doi:10.1007/s00339-014-8472-6
33
E Richard, S T Aruna, B J Basu. Superhydrophobic surfaces fabricated by surface modification of alumina particles. Applied Surface Science, 2012, 258(24): 10199–10204 https://doi.org/10.1016/j.apsusc.2012.07.009
34
N Cao, Y Y Miao, D L Zhang, et al.. Preparation of mussel-inspired perfluorinated polydopamine film on brass substrates: Superhydrophobic and anti-corrosion application. Progress in Organic Coatings, 2018, 125: 109–118 https://doi.org/10.1016/j.porgcoat.2018.09.007
35
J Kuang, Z Ba, Z Li, et al.. Fabrication of a superhydrophobic Mg‒Mn layered double hydroxides coating on pure magnesium and its corrosion resistance. Surface and Coatings Technology, 2019, 361: 75–82 https://doi.org/10.1016/j.surfcoat.2019.01.009
36
G Zhang, A T Tang, L Wu, et al.. In-situ grown super- or hydrophobic Mg‒Al layered double hydroxides films on the anodized magnesium alloy to improve corrosion properties. Surface and Coatings Technology, 2019, 366: 238–247 https://doi.org/10.1016/j.surfcoat.2019.03.016
37
L Zhao, Q Liu, R Gao, et al.. One-step method for the fabrication of superhydrophobic surface on magnesium alloy and its corrosion protection, antifouling performance. Corrosion Science, 2014, 80: 177–183 https://doi.org/10.1016/j.corsci.2013.11.026
38
P Ding, Z Z Li, Q Wang, et al.. In situ growth of layered double hydroxide films under dynamic processes: Influence of metal cations. Materials Letters, 2012, 77: 1–3 https://doi.org/10.1016/j.matlet.2012.02.124
39
S Ozturk, D Balkose, S Okur, et al.. Effect of humidity on electrical conductivity of zinc stearate nanofilms. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2007, 302(1‒3): 67–74 https://doi.org/10.1016/j.colsurfa.2007.01.039
40
Y H Wang, W Wang, L Zhong, et al.. Super-hydrophobic surface on pure magnesium substrate by wet chemical method. Applied Surface Science, 2010, 256(12): 3837–3840 https://doi.org/10.1016/j.apsusc.2010.01.037
41
J Xi, L Feng, L Jiang. A general approach for fabrication of superhydrophobic and superamphiphobic surfaces. Applied Physics Letters, 2008, 92(5): 053102 https://doi.org/10.1063/1.2839403
42
F Zhang, Z G Liu, R C Zeng, et al.. Corrosion resistance of Mg‒Al-LDH coating on magnesium alloy AZ31. Surface and Coatings Technology, 2014, 258: 1152–1158 https://doi.org/10.1016/j.surfcoat.2014.07.017
43
F Zhang, C L Zhang, R C Zeng, et al.. Corrosion resistance of the superhydrophobic Mg(OH)2/Mg‒Al layered double hydroxide coatings on magnesium alloys. Metals, 2016, 6(4): 85 https://doi.org/10.3390/met6040085