Hastelloy Alloys
Hastelloy Alloys
Hastelloy is a trademarked name for a family of corrosion-resistant metal alloys primarily composed of nickel, with other elements such as molybdenum, chromium, and iron. These alloys are designed for high-performance applications where resistance to corrosion, oxidation, and high-temperature stability is essential.
Key Types of Hastelloy Alloys and Their Common Uses
Hastelloy C-276
◆ Composition: Primarily nickel, with molybdenum and chromium as key elements.
◆ Properties: Excellent resistance to a wide variety of aggressive chemical environments, especially in the presence of chlorine, sulfuric acid, and hydrochloric acid. It is highly resistant to stress corrosion cracking.
◆ Applications: Chemical processing, power plants, pollution control equipment, and pharmaceutical manufacturing.
Hastelloy C-22
◆ Composition: Similar to C-276 but with a slightly different balance of alloying elements, including more chromium.
◆ Properties: Excellent resistance to pitting, crevice corrosion, and stress corrosion cracking, especially in highly aggressive environments like hydrochloric acid, sulfuric acid, and other chlorides.
◆ Applications: Chemical and petrochemical processing, marine environments, flue gas desulfurization.
Hastelloy B-2
◆ Composition: Primarily nickel with high levels of molybdenum.
◆ Properties: Outstanding resistance to hydrochloric acid and other reducing environments.
◆ Applications: Ideal for applications where exposure to hydrochloric acid in reducing conditions is expected.
Hastelloy X
◆ Composition: A nickel-based alloy with significant amounts of iron and chromium.
◆ Properties: Excellent high-temperature strength, oxidation resistance, and weldability. It can maintain its structural integrity at temperatures as high as 2,000°F (1,093°C).
◆ Applications: Aerospace and gas turbine applications, combustion chambers, and exhaust systems.
Hastelloy C-4
◆ Composition: Nickel, molybdenum, and chromium, with small amounts of iron and tungsten.
◆ Properties: Excellent resistance to both oxidizing and reducing environments, particularly in acid-rich environments.
◆ Applications: Applications involving sulfuric acid, phosphoric acid, and other aggressive chemicals.
General Applications of Hastelloy Alloys
Chemical Processing
Due to their exceptional corrosion resistance, Hastelloy alloys are used in reactors, heat exchangers, and piping systems that handle aggressive chemicals.
Aerospace
Hastelloy X, for example, is used in jet engines, gas turbines, and other components that need to withstand high temperatures and oxidation.
Marine
The alloys are often used in saltwater environments where resistance to corrosion is crucial.
Pharmaceutical
Used in equipment for the production of drugs and in environments requiring sterile conditions due to their resistance to corrosion and contamination.