A297 HK

Grade HK is a heat-resistant austenitic stainless steel casting alloy defined by ASTM A297/A297M, designed for service in high-temperature applications where both oxidation and carburization resistance are required. With a typical composition of approximately 25% chromium and 20% nickel, HK provides a well-balanced combination of strength, corrosion resistance, and thermal stability. This alloy is commonly used in furnace components, reformer tubes, radiant sections, and heat-treat fixtures that are subjected to sustained thermal exposure. Its stable microstructure and resistance to scaling make it a standard choice for petrochemical, metallurgical, and industrial heating environments.