Effects of Mo composites on the corrosion behaviors of low alloy steel

Abstract

By using electrochemical and weight loss methods, the effect of MoO₄ ²⁻ on the corrosion behaviors of low alloy steel was investigated in the 55%LiBr+0.07 mol/L LiOH solution at high temperature. The results show that MoO₄ ²⁻, being an anodic inhibitor, would form a passive film rapidly and impede both anodic and cathodic reactions. Moreover, Na₂MoO₄ effectively prevents corrosion in 55%LiBr+0.07 mol/L LiOH solution when its concentration is higher than 200 mg/L. Some elements of alloy, such as chromium and nickel, may cause the widening of passive potential region and the decrease of passive density, which indicates that the corrosion resistance increases. AES analysis shows that molybdenum participates in forming a protection film. The synergistic effect between chromium and molybdenum induces Cr-steel to be in passive state in lower Na₂MoO₄ concentration.

Keywords

lithium bromide / low alloy steel / inhibitor / corrosion

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