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Subject: search.filters.subject.AZ31 magnesium alloy

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    Exploring the Corrosion Inhibition Properties of an Anionic Gemini Surfactant Based on an Ethylenediaminetetraacetic Acid Derivative on AZ31 Alloy
    (John Wiley and Sons Inc, 2021) Acharya, G.M.; Shetty, N.A.
    Novel sodium 2,2?-(7,16-dihexyl-8,15-dioxo-7,10,13,16-tetraazadocosane-10,13-diyl)diacetate was prepared by treating ethylenediaminetetraacetic acid dianhydride with N-dihexylamine. The surfactant was used as a corrosion inhibitor on AZ31 alloy. FT-IR spectroscopy, NMR spectroscopy and LC-MS techniques were used to characterize the synthesized anionic inhibitor. The theoretical studies, performed by using the DFT simulations revealed in-depth information on the frontier molecular orbitals and electronic properties of the inhibitor. Potentiodynamic polarization and electrochemical impedance spectroscopy methods were used to determine the corrosion inhibition ability of the synthesized surfactant. The adsorption of the surfactant on the surface of AZ31 Mg alloy obeyed Langmuir isotherm with predominantly physical adsorption and partial chemisorption. SEM-EDX and XPS were used to understand the surface morphologies of the corroded AZ31 alloy. The quantum chemical simulations were used to get the correlation between their structural, molecular geometry, and experimental results. © 2021 Wiley-VCH GmbH
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    Influence of Media pH on Corrosion Behaviour of AZ31 Magnesium Alloy in Chloride and Sulphate Media
    (Pleiades journals, 2021) M Gururaj Acharya; A Nityananda Shetty
    Abstract: AZ31 alloy has excellent properties like ultra-low density, good energy absorption, and high damping performance but has poor corrosion resistance. The influence of media pH on the corrosion of AZ31 alloy in chloride and sulphate media was investigated using such electrochemical techniques as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The tests were carried out by varying pH in different concentrations (0.05–0.25M) of the media. The surface morphologies and surface compositions of the corroded alloy surfaces were analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. Conclusively, the recorded results reflect a trend of a higher corrosion rate at higher concentrations of the media; and an increase in the corrosion rate on decreasing the pH of the media. In the studied pH range, the alloy showed a higher corrosion resistance at pH 11 and a lower corrosion resistance at pH 3. © 2021, Allerton Press, Inc.
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    Experimental and Theoretical Studies on an Anionic Gemini Surfactant as Corrosion Inhibitor for AZ31 Magnesium Alloy
    (Springer Science and Business Media Deutschland GmbH, 2022) Acharya, M.G.; Nityananda Shetty, A.N.
    Abstract: Sodium 2,2′-(13,22-dimethyl-14,21-dioxo-13,16,19,22-tetraazatetratriacontane-16,19-diyl)diacetate anionic Gemini surfactant was synthesized and utilized as a corrosion inhibitor for AZ31 alloy. The corrosion inhibition property was investigated using electrochemical methods. The surface investigation of the alloy was achieved using SEM–EDX and XPS. The strength of inhibitor to inhibit corrosion depends on the surfactant concentration, the higher inhibition efficiency was exhibited when the surfactant concentration was higher. The inhibitor appeared as a mixed-type inhibitor. The inhibiting effect of Gemini surfactant showed rapid adsorption on the alloy surface. The experimental results were related to the theoretical findings obtained from the studies based on density function theory (DFT). Graphical Abstract: [Figure not available: see fulltext.]. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
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    Performance of anionic dimeric surfactant on AZ31 Magnesium alloy in neutral medium unveiled through experimental and theoretical investigation
    (Springer, 2024) Acharya, M.G.; Nityananda Shetty, A.N.
    The synthesis of a novel eco-friendly anionic Gemini surfactant, pursuing three parameters of green chemistry: economic, environmental factor, and mass reaction efficiency is developed as a corrosion inhibitor for AZ31 Mg alloy. Herein, the corrosion inhibition ability of novel EDTA-based dimeric surfactant on AZ31 Mg alloy in corrosive media with varying concentrations of NaCl and Na2SO4 at temperatures between 30–50 °C were studied. The surfactant’s molecular structure is affirmed by FT-IR, NMR, and LC–MS techniques. Electrochemical techniques and surface morphology were employed to evaluate the corrosion inhibition efficiency. The inhibitor studied exhibited appreciable corrosion inhibition at 30 °C. The surfactant shows physical adsorption as per the data obtained in the Gibbs free energy and enthalpy of adsorption studies. The adsorption of the inhibitor was found to be a film-like layer on the surface of AZ31 Mg alloy and, is confirmed by SEM–EDX and XPS techniques. In addition, theoretical simulations were performed to compare with experimental results. Conclusively, the work provides a deeper understanding of the intricacies involved in the development of a new anionic dimeric surfactant as an effective corrosion inhibitor. © The Author(s) 2024.