Effects of Zn²⁺Concentration on the Corrosion of Mild Steel in NaCl Aqueous Solutions

Abstract

The effects of Zn 2+ concentration on the corrosion of mild steel were investigated by immersion tests and electrochemical tests in NaCl aqueous solutions. Immersion tests showed the minimum corrosion rate in the Zn 2+ rich solution. The specimens immersed in the Zn 2+ rich solution showed comparatively smooth surfaces as compared to specimens immersed in Zn 2+ free NaCl aqueous solutions observed by scanning electron and atomic force microscopes. The Zn 2+ attached to the steel surface and formed a layer, suggested from the results of X-ray photoelectron and Auger electron spectroscopy observations. The coverage of the Zn layer increased with increasing Zn 2+ concentrations in the solution, thereby suppressing the corrosion rate of the steel.

The influence of Zn2+ on stress corrosion cracking severity in a highly sensitised Al–Mg alloy

“…Liu et al also demonstrated that Zn 2+ additions reduce ORR kinetics on AA7050-T7451 through potentiodynamic analysis [39]. Numerous studies exist on steels, demonstrating that Zn 2+ content slows anodic and cathodic reactions on the steel surface by depositing layers of corrosion product and/ or adsorbing to the alloy surface over extended exposure [40][41][42][43][44]. In sulphuric acid, the presence of Zn cations has been demonstrated to inhibit hydrogen evolution and thus hydrogen embrittlement in iron [45].…”

In-Situ Detection of Early Corrosion of Ferritic Cr-Mo Steel in Aqueous Solutions of different Anions using Laser Raman Spectroscopy

“…Islam et al 27 studied the corrosion inhibition of mild steel by metal cations in high pH simulated fresh water at different temperatures and the effects of Zn 2+ concentration on the corrosion of mild steel in NaCl solutions. 28 The corrosion behaviour of modified 9Cr-1Mo steel in aqueous solution has been extensively studied by electrochemical methods in different aqueous media [29][30][31] such as sea water, 32 binary and ternary mixtures of concentrated phosphoric acid, acetic acid, sulphuric acid and formic acid environments, 29,31 organic constituents of bio-oils, including catechol, formic acid, and their mixtures as well as lactobionic acid 30 at different concentrations. These studies were focused on general (uniform) and localized (pitting) corrosion susceptibility behaviour, by observing the current density variation on either sweeping or at a fixed potential.…”