A297 HN

Grade HN is a high-temperature austenitic stainless steel casting alloy defined by ASTM A297/A297M, designed for service in environments requiring both oxidation resistance and mechanical strength at elevated temperatures. With a typical composition of approximately 20% chromium and 20% nickel, HN provides a stable austenitic structure and good resistance to scaling and thermal fatigue. HN is used in applications such as furnace parts, heat-treat fixtures, and other components subjected to moderate thermal cycling and oxidation. Its balanced alloy content makes it a versatile material for industrial heating systems and general high-temperature service where performance and cost-effectiveness are both important.