Nitronic 40 /21-6-9 (AMS 5656 / AMS 5595)

Technical Data Sheet


Chemical Composition Limits
Weight% C P Si Ni Fe Mn S Cr N Mo Cu
Nitronic 40 (21-6-9) 0.04 max 0.060 max 1.00 max 5.5-7.5 Bal 8-10 0.030 max 19-21.5 0.15-0.40 0.75 max 0.75 max

Nitronic 40 (21-6-9) is a high-manganese nitrogen strengthened stainless steel. Nitronic 40 properties include high strength in the annealed condition, excellent resistance to corrosion at high temperatures, readily weldable and it can also be fabricated. Nitronic 40 is used in a numerous applications including aircraft engine components, chemical processing, pollution control equipment.      

Typical Mechanical Properties


Alloy Cross Section Size Test Direction Yield Strength 0.2% Ultimate Tensile Strength Elongation in 2"(%)
Reduction of Area % Rockwell B Hardness
ksi MPa ksi MPa
Nitronic 40 (21-6-9) 6" (152mm) sq Longitudinal 62 428 95 655 46 69  
Nitronic 40 (21-6-9) 6" (152mm) sq Transverse 52 358 93 641 30 45  
Nitronic 40 (21-6-9) 4" (102mm) sq Longitudinal 56 386 97 668 53 73  
Nitronic 40 (21-6-9) 1" (25.4mm)sq Longitudinal 52 358 101 696 53 73 90

Nitronic 40 (21-6-9) is available as Bar, Wire, Sheet, Plate, Strip, Forgings, Extrusions, Rings, Tube (Welded or Seamless), Billet and Welding Wire. For all stock availability contact Sales.

AMS 5656 Bar / Wire
AMS 5595 Sheet / Plate / Strip
AMS 5561 Welded tube
AMS 5562 Seamless Tube
AMS 5656 Rings / Extrusions
ASTM A276 / ASME SA276
ASTM A412 / ASME SA412
ASTM A580 / ASME SA580
UNS S21906

At Aircraft Materials all stock items can be shipped out within 24 hours, usually within the same day. Even cutting orders for bar or sheet can be processed and dispatched the same day, and for time-critical situations such as AOGs, we have a dedicated AOG service desk ready to help (

Thanks to our global logistics network we can source from anywhere in the world in just a few days. We use a range of transport partners to enable us to ship overnight within the U.K. and Europe and provide fast shipping solutions to the rest of the world. If your requirement is urgent we can offer a priority shipping service, but also if time is not so critical we can offer more cost-effective options to ensure you get the best value for money. To find out more about our services click here.

Every effort is made to ensure that technical specifications are accurate. However, technical specifications included herein should be used as a guideline only. All specifications are subject to change without notice.

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