INCOLOY ® alloy 25-6MO (UNS N08926/W. Nr. 1.4529, formerly UNS N08925) is a super-austenitic stainless steel containing 6% molybdenum and enhanced by an addition of nitrogen. The nickel and chromium contents of this alloy make it resistant to a wide range of corrosive environments. The alloy is especially resistant to non-oxidizing acids such as sulfuric and phosphoric. The high molybdenum content and nitrogen provide resistance to pitting and crevice corrosion, while copper enhances resistance to sulfuric acid.

INCOLOY alloy 25-6MO is a fully austenitic alloy containing 6% molybdenum and offering excellent corrosion resistance in a wide variety of aggressive, aqueous environments. It replaces the conventional, austenitic stainless steels (AISI 316 and 317), where their capabilities are pushed to their performance limits. The alloy, therefore, falls into a "super austenitic stainless steel" category. (See Figure 1.) It can also represent a cost-effective alternative to the higher nickel alloys in some marine and chemical processing environments.

One of the outstanding attributes of INCOLOY alloy 25-6MO is its resistance to environments containing chlorides or other halides. This alloy is especially suited to handle high-chloride environments such as brackish water, sea water, caustic chlorides and pulp mill bleach systems. Applications include chemical and food processing, pulp and paper bleaching plants, marine and offshore platform equipment, salt plant evaporators, air pollution control systems, and condenser tubing, service water piping, and feedwater heaters for the power industry.