Stainless Steel 440C

Technical Data Sheet


Chemical Composition Limits
Weight% C Si Mn P+S Cr Mo Ni Others
0.95/ 1.2 1.0 max 1.0 max 0.04 P
0.03 S
16.0 / 18.0 0.75 - -
AFNOR Z100 CD 17 0.90/ 1.2 1.0 max 1.0 max 0.04 P
0.03 S
16.0 / 18.0 0.35 / 0.75 0.50 max Cu 0.50 max
AMS 5630 0.95/ 1.2 1.0 max 1.0 max 0.04 P
0.03 S
16.0/ 18.0 0.4/ 0.65 0.75 max Cu 0.50 max
WS 1.4125
Chronifer X 105 CrMo17
Z100 CD 17
0.95/ 1.2 1.0 max 1.0 max 0.015 S max 16.0/ 18.0 0.8 max - -

AISI 400C is a high carbon chromium steel is designed to provide stainless steel properties with maximum hardness. After heat-treatment Type 440C attains the highest hardness of any stainless steel (about 60 HRC). This stainless steel is principally used for bearing assemblies including ball bearings and should be considered for needle valves and ball check valves.

Typical Mechanical Properties


Material Condition
Yield Strength 0.2% (MPa) Ultimate Tensile Strength (MPa) Elongation 2"% Reduction of Area Brinell Hardness
Alloy 440C Hardened 1900°F, oil quench, tempered 600°F 1896 1965 2 10 580

Alloy 440C is available in Bar (Flat, Hexagon, Round, Square), Wire, Billet, Rod. For all stock availability contact Sales.

440C Vac Melt
AMS 5618 Bars / wire / forging (VM)
AMS 5630 Bar, Wire, Forgings
AMS 5880 Bars / wire (bearing apps)
ASTM A276 / ASME SA276
ASTM A314 / ASME SA314
ASTM A473 / ASME SA473
ASTM A484 / ASME SA484
ASTM A493 / ASME SA493
ASTM A756 / ASME SA756
ASTM A580 / ASME SA580
WS 1.4125
UNS S44004
RBO 160-064

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.

Sell your Stock Online at