Influence of sodium alginate inhibitor addition on the corrosion protection performance of AZ91D magnesium alloy in NaCl solution

Research output: Contribution to journalArticlepeer-review

Authors

External organisations

  • Nanjing Hydraulic Research Institute
  • Nanjing Institute of Technology
  • School of Chemical Engineering Birmingham

Abstract

Purpose - This paper aims to investigate the inhibition effect of sodium silicate (SS), sodium alginate (SA) and sodium tungstate (ST) on the corrosion behavior of AZ91D magnesium alloy in 3.5 per cent NaCl solution through polarization curve test at room temperature, electrochemical impedance spectroscopy and weight loss measurement. Design/methodology/approach - The influence of SA concentration on the inhibition efficiency of the corrosion inhibitor was mainly analyzed. The corrosion morphology and inhibition mechanism of the samples were also analyzed with scanning electron microscopy and energy-dispersive spectroscopy. Findings - The results show that with the increase of SA concentration, the corrosion inhibition first increases and then decreases. When SA concentration is 0.03 mol/L, the inhibition efficiency is the highest, reaching 98 per cent. The adsorption film formed by SA and other deposition films produce a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy. Originality/value - The adsorption film formed by SA with other deposition films produces a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy. With the increase of SA concentration, the corrosion inhibition first increases and then decreases. When the concentrations of SA, SS and ST are 0.03 mol/L, 0.015 mol/L and 0.02 mol/L, respectively, the inhibition efficiency of the inhibitor is the highest, reaching 98 per cent.

Details

Original languageEnglish
Pages (from-to)486-491
Number of pages6
JournalAnti-Corrosion Methods and Materials
Volume64
Issue number5
Publication statusPublished - 13 Feb 2017

Keywords

  • Composite inhibitor, Inhibition mechanism, Magnesium alloy, Sodium alginate