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 we specialise in the rapid turn-around of orders, with most stock items ready for shipping out the same day to anywhere in the world. For time-critical orders, such as AOGs use our AOG service desk (, the team are dedicated to processing and dispatching orders on the same day, even for cutting orders on bar and sheet products.

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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.