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This paper aims to acquire the current density distribution on dissolving of Mg, MgZn₂ (η -phase), Mg₂Si (ß-phase) and Al₄Cu₂Mg₈Si₇ (Q-phase) surface in NaCl solutions.

MgZn₂ (η -phase), Mg₂Si (ß-phase) and Al₄Cu₂Mg₈Si₇ (Q-phase) are important intermetallic compounds found in aluminum alloys. Insitu scanning vibrating electrode technique (SVET) was used to acquire the current density distribution on dissolving of Mg, MgZn₂ (η -phase), Mg₂Si (ß-phase) and Al₄Cu₂Mg₈Si₇ (Q-phase) surface in NaCl solutions scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) was used to characterize the corroded surface.

SVET maps reveal that these compounds display characteristic dissolution features. Mg and MgZn₂ displayed localized anodic and cathodic sites while that of Al₄Cu₂Mg₈Si₇ > Mg₂Si displayed a diffused distribution of anodic and cathodic sites. The magnitude of the integrated anodic current densities on the compounds was noted to decrease with the progress of time, and the order of the magnitude of the current density with respect to the compounds is Mg > Mg₂Si > Al₄Cu₂Mg₈Si₇ > MgZn₂. SEM/EDX reveal that the highest mass loss recorded after the SVET test was manifested by Mg₂Si followed by MgZn₂ then Al₄Cu₂Mg₈Si₇.

Auxiliary information on the current density distribution on the corroding sample surface at the microscopic scale has been provided by SVET thereby taking care of certain limitations of traditional corrosion monitoring techniques such as gravimetric, hydrogen evolution and electrochemical measurements.

The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.

In line with current research efforts to develop eco-friendly strategies for corrosion mitigation, the purpose of this study is to appraise the anti-corrosion potential of selected amino acids on magnesium corrosion in sodium chloride solutions.

The corrosion inhibition of magnesium in aqueous solutions in the presence of benign, eco-friendly and readily available amino acids (alanine, arginine, histidine, lysine, proline) were evaluated using electrochemical methods.

Amino acids suppressed magnesium corrosion rate in aqueous sodium chloride solutions. The order of inhibition efficiency (%IE) was as follows: alanine < arginine < histidine < lysine < proline. The open circuit potential shift with respect to the blank was less than 0.085 V_SCE, indicating that the amino acids are mixed-type corrosion inhibitors. In addition, the %IE of the amino acids was inversely proportional to the molecular weight. The results obtained indicate that the amino acids can serve as sustainable eco-friendly corrosion inhibitors for magnesium with the best inhibition efficiency attributed to proline with an efficiency of 85.1%.

New information on the application of amino acids as green sustainable corrosion inhibitors is provided herein.