21-6-9 (AMS 5561)

21-6-9 stainless steel is a high manganese content austenitic alloy strengthened with nitrogen. The material provides outstanding oxidation resistance at elevated temperatures and excellent air corrosion resistance in the annealed condition. 21-6-9 possesses lower carbon content resulting in an alloy with excellent resistance to intergranular corrosion, even after welding. The weldability of the material is good by standard methods. The alloy combines excellent impact toughness with high mechanical strength and promotes workability like 301, 302, 304 and 316 stainless steel.

Non-Magnetic

21-6-9 stainless is non-magnetic (even after cold working) and may be stress-relieved below 705°C (1300°F). However, such a process will reduce the mechanical properties of the alloy, particularly at temperatures above 1250°F. Annealing will soften the material, which will improve formability. The alloy finds typical use in aerospace applications, including hydraulic tubes and aircraft engine components.

Stock Availability

We stock 21-6-9 stainless steel tubes in various sizes and welded forms.