Effect of naturally formed oxide films and other variables in the early stages of Mg-alloy corrosion in NaCl solution

Feliú, S.; Maffiotte, C.; Samaniego, Alejandro; Galván, J.C.; Barranco, Violeta

doi:10.1016/j.electacta.2011.02.077

Cited by 53 publications

(29 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…22,30,[35][36][37] Impedance spectra were recorded with the following AZ91D alloy specimens: (i) with a native oxide layer, (ii) potentiostatically anodized, and (iii) anodized and modified with the SAMs of PA and SA. For these measurements the surface films of anodized specimens were modified with SAMs of PA and SA during a period of 24 h. As an example, Fig.…”

Section: Resultsmentioning

confidence: 99%

Surface Modification of Biodegradable Magnesium Alloys

Grubač¹,

Rončević²,

Metikoš‐Huković³

et al. 2012

J. Electrochem. Soc.

View full text Add to dashboard Cite

The use of self-assembling monolayers (SAM) of long chain carboxylic acids has a potential for designing specific interface architectures in degradable implants technology. In this paper, the native and anodically formed oxide films on the Mg-alloy (AZ91D) surface were modified with the SAMs of palmitic acid (PA) and stearic acid (SA) to protect the alloy degradation in a physiological solution. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were used to evaluate chemical composition, bonding modes of acids to the substrate, and structural properties (ordering and close-packing) of the surface layers. The results obtained by electrochemical impedance spectroscopy (EIS) have shown a beneficial effect of anodization and especially of the oxide layer modification by forming SAMs of PA and SA on the corrosion properties of AZ91D alloy in physiological solutions.Magnesium and its alloys are ideal structural materials for the lightweight engineering applications due to their remarkable properties such as low density, high specific strength, high thermal conductivity, and electromagnetic interference resistance. But so far, their application has been limited mostly due to the poor corrosion and wear resistance. 1 As a potential biodegradable implant material, magnesium shows many advantages over current metallic materials as well as biodegradable polymeric and ceramic materials because it is an essential element and in the human body its concentration is high . 1-3 However, in a solution containing Cl − ions like body fluids magnesium and its alloys easily corrode, and their successful application as degradable orthopedic implants has been mainly inhibited due to the high degradation rates and a consequent loss of the mechanical integrity. 2-6 Various surface treatments have been applied to Mg and its alloys to improve their corrosion resistance and the lifetime of implants including anodization, 7, 8 deposition of chemical conversion layers, 9 treatments based on the sol-gel application, 10 and the surface modification by formation of SAMs of long-chain carboxylic acids. 11, 12 The chemisorption of saturated long-chain (C 16 , C 18 ) carboxylic acids has been also studied on many surfaces such as aluminum oxide, 13-15 iron, 16, 17 zinc, 17 and steel. 18 As endogenous compounds and the main components of fats, fatty acids are very biocompatible substances. According to the Food and Agriculture Organization of the United Nations (FAO) recommendation, the intake of saturated fatty acids by adults should not exceed 10% of the total energy consumption. 19 However; the results on the interaction of carboxylic acids with the magnesium/AZ91D alloy surface are not consistent. While the theoretical studies predict that the most stable adsorbed configuration is one in which the carboxyl group is attached by its each oxygen atom to two separate magnesium ions, 20 the experimental results have confirmed the existence of monodentate bonding, 11 and even the electrostatic attraction of magne...

show abstract

Section: Resultsmentioning

confidence: 99%

Surface Modification of Biodegradable Magnesium Alloys

Grubač¹,

Rončević²,

Metikoš‐Huković³

et al. 2012

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…As shown in Fig. 8a, Mg 2p peak obtained on the outmost surface of oxidized Mg-3Y-2.5Zn alloy contains one component at a binding energy of 50.8 eV, this peak associated with the presence of magnesium in the form of MgO, Mg(OH) 2 or MgCO 3 [11,30]. The O 1s spectra of the oxidized Mg-3Y-2.5Zn alloy also contains one single component at about 532.1 eV and corresponding to Mg(OH) 2 or MgCO 3 [30].…”

Section: Characterization Of the Oxide Filmsmentioning

confidence: 97%

Effect of Zn addition on the oxidation property of Mg-Y alloy at high temperatures

Jiang

et al. 2016

Journal of Alloys and Compounds

View full text Add to dashboard Cite

“…During Mg dissolution, Mg 2+ ions diffuse to react with the hydroxyl ions OH − to form the porous layer of Mg(OH) 2 on top of the inner barrier film formed by MgO [24]. In contact with a NaCl solution, the adsorbed chloride ions on the surface of magnesium alloys tend to transform Mg(OH) 2 into soluble MgCl 2 [25,26] and therefore creates more film free areas where magnesium is corroded.…”

Section: Introductionmentioning

confidence: 98%