Iso Corrosion Curves:
Nitric acid is an oxidizing chemical, which makes it particularly difficult to handle. Zirconium, Hastelloy B series alloys, and in high concentrations, even Hastelloy C276 will experience corrosion failure in the presence of a strong oxidizer like nitric acid. Fortunately, there are materials that provide resistance to oxidizers. Because of its high chromium, Incoloy 825 provides excellent resistance to nitric acid solutions at all concentrations and temperatures up to and including boiling 65%. Incoloy 800 also offers excellent protection in nitric acid with stress-corrosion resistance significantly superior to austenitic stainless steels. Hastelloy C22 also performs very well in nitric acid environments.