UNS N06625

Alloy 625 is a nickel-chromium-molybdenum-niobium alloy that exhibits excellent resistance to pitting, crevice corrosion, intergranular corrosion, and stress corrosion cracking. The alloy provides good corrosion resistance to inorganic acids such as nitric, phosphoric, sulfuric, and hydrochloric acids. The alloy is also used in applications with alkali and organic acids, and seawater. Alloy 625 also exhibits good high temperature strength and can be used for short term exposures to 1,500 °F; however long-term exposures should be limited to 1,100 °F. This alloy is used in pulp and paper processes, acid cooling heat exchangers, and in high temperature aircraft service.