Bearing Steels - M50 AMS 6490/6491

M50 AMS 6490/6491

M50 is a premium-melted alloy. It offers excellent resistance to multi-axial stresses and good resistance to oxidation. The product is refined using vacuum-induction melting (VIM) and vacuum-arc remelting (VAR) processes.
It possesses high compressive strength suitable for a high speed steel tool. It also has a high degree of cleanliness therefore can be finished to a high luster. M50 is a bearing steel suitable for use within the missile and bearing industry, offering high wear resistance and strength at elevated temperatures. Bearings within aircrafts and gas turbines are other typical applications of this alloy.
M50 could also be used in tooling applications where high levels of performance are required.

Chemical Composition

Spec: AMS 6490/6491

Chemical Element % Present
Carbon (C) 0.0 - 0.85
Manganese (Mn) 0.0 - 0.30
Silicon (Si) 0.0 - 0.20
Molybdenum (Mo) 0.0 - 4.25
Vanadium (V) 0.0 - 1.00
Chromium (Cr) 0.0 - 4.10
Iron (Fe) Balance


Physical PropertyValue
Density 7.87 g/cm³
Melting Point 86-203 °C

Alloy Designations

AMS 6490
AMS 6491
ASTM A600 (M 50)
ASTM A600 (M50)
DIN 1.3551

Supplied Forms

  • Bar
  • Forgings
  • Wire
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Last Datasheet Revision

18 July 2019


This Data is indicative only and as such is not to be relied upon in place of the full specification. In particular, mechanical property requirements vary widely with temper, product and product dimensions. All information is based on our present knowledge and is given in good faith. No liability will be accepted by the Company in respect of any action taken by any third party in reliance thereon.

Please note that the 'Datasheet Update' date shown above is no guarantee of accuracy or whether the datasheet is up to date.

The information provided in this datasheet has been drawn from various recognised sources, including EN Standards, recognised industry references (printed & online) and manufacturers’ data. No guarantee is given that the information is from the latest issue of those sources or about the accuracy of those sources.

Material supplied by the Company may vary significantly from this data, but will conform to all relevant and applicable standards.

As the products detailed may be used for a wide variety of purposes and as the Company has no control over their use; the Company specifically excludes all conditions or warranties expressed or implied by statute or otherwise as to dimensions, properties and/or fitness for any particular purpose, whether expressed or implied.

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