Hydrogen Evolution and Corrosion Behavior of Fe-Ni Alloys in H₂SO₄—Effect of Temperature, Cl⁻ and Benzotriazole

The corrosion of iron-nickel alloys in deaerated 1N H₂SO₄ in the absence and presence of chloride ions and benzotriazole (BTA) between 23 to 75 C has been investigated. A marked decrease in the corrosion rate of the uninhibited alloys in the absence and presence of chloride ions was observed as the iron content decreased from pure iron to 60% Fe at all temperatures. On the other hand, below 60% Fe the corrosion rate of the alloys did not differ as substantially. Apparent activation energies for corrosion of Fe-Ni alloys in 1N H₂SO₄ decrease with increase in nickel content. Benzotriazole was an effective corrosion inhibitor of the Fe-Ni alloys in 1N H₂SO₄ even at 75 C.