NC2295 Alloy C22 (Hastelloy C22) sheet metal

Description of Alloy C22 Sheet

ALLOY22 is a Ni-Cr-Mo alloy with tungsten and extremely low amounts of carbon and silicon. The chromium content, ranging from 20.0 to 22.5%, contributes to resistance against oxidising media. The molybdenum and tungsten levels provide resistance against reducing media. The nickel alloy resists corrosion in oxidising aqueous environments, including conditions with moist chlorine and mixtures of nitric acid or oxidising acids that contain chloride ions. It also performs against oxidising acidic chlorides, moist chlorine, formic and acetic acids, iron and copper chlorides, seawater, brine and many mixed chemical solutions, both organic and inorganic. The alloy meets performance criteria in process streams that expose it to both reducing and oxidising conditions, thereby supporting extended use in multipurpose facilities.

This nickel alloy resists the formation of grain-boundary precipitates in the heat-affected zone. It is therefore suitable for most chemical process applications in the welded state.

Alloy C-22 should not be used at operating temperatures exceeding 1250° F, as above this temperature harmful phases form.

Specifications of Alloy C22 Sheet

ASTM Specifications

Applications of Alloy C22 Sheets

• Chimney linings:
• The alloy meets corrosion performance criteria under both oxidising and reducing conditions, thereby ensuring its suitability for chimney linings.
• Pipes:
• The alloy demonstrates resistance to corrosion when exposed to a range of aggressive media over extended periods.
• Dampers:
• The alloy’s resistance to corrosion and oxidation ensures consistent performance when it is exposed to corrosive gases.
• Washers:
• The alloy reliably meets durability criteria against pollutants and chemical agents in washing applications.
• Heat exchangers:
• The alloy exhibits thermal stability and resistance to both oxidising and reducing conditions, thereby maintaining efficiency in heat exchangers.
• Reaction vessels:
• The material maintains its structural integrity under exposure to acids and chlorides, as required for reaction vessels.
• Evaporators:
• The alloy’s corrosion resistance is critical when processing concentrated solutions and corrosive substances, thereby meeting operational standards in evaporators.