1.4550 Stainless Steel Composition for High-Temperature Corrosion Resistance
1.4550 (X6CrNiNb18-10) is a niobium-stabilized austenitic stainless steel grade specified under EN 10028-7 and EN 10088-2, equivalent to the widely used 347. Its composition includes 17–19% chromium, 9–13% nickel, and niobium added in proportion to carbon content (Nb ≥ 10×C%). Niobium prevents carbide precipitation during welding or high-temperature service, significantly improving resistance to intergranular corrosion.
Compared with 1.4301 (304) and 1.4541 (321), 1.4550 offers superior stability at elevated temperatures and can operate continuously above 600°C without sensitization. This makes it suitable for heat exchangers, exhaust systems, boiler components, and high-temperature pressure equipment. It maintains good weldability and does not require post-weld heat treatment to restore corrosion resistance. 1.4550 is available as sheets, plates, strips, tubes, and bars. It is widely used in chemical processing, petrochemical plants, aerospace exhaust systems, heat-resistant structures, and food-grade equipment. Its niobium-stabilized design ensures reliable performance in high-temperature and welded applications, serving as a heat-resistant upgrade to the 304 stainless steel family.
Compared with 1.4301 (304) and 1.4541 (321), 1.4550 offers superior stability at elevated temperatures and can operate continuously above 600°C without sensitization. This makes it suitable for heat exchangers, exhaust systems, boiler components, and high-temperature pressure equipment. It maintains good weldability and does not require post-weld heat treatment to restore corrosion resistance. 1.4550 is available as sheets, plates, strips, tubes, and bars. It is widely used in chemical processing, petrochemical plants, aerospace exhaust systems, heat-resistant structures, and food-grade equipment. Its niobium-stabilized design ensures reliable performance in high-temperature and welded applications, serving as a heat-resistant upgrade to the 304 stainless steel family.