440C Stainless Steel

Alloy 440C (AMS 5630, 1.4125) is commercially more available when compared to 440B and offers the highest carbon content of all 440 series products.

440C finds use in applications where increased strength with moderate corrosion resistance is essential. The alloy has enough chromium content for 440C to retain its status as stainless steel, regardless of the high carbon levels. Once heat-treated, the alloy is harder and more wear-resistant than other stainless steels. Machining is straightforward in the annealed condition, although much more problematic once hardened.


Typical commercial applications include:

  • Higher strength
  • Higher carbon content
  • Moderate wear resistance
  • The hardest stainless steel after heat-treatment

Application examples include bushes, bearings and valve parts. 440C is most commonly used for producing bearing components and high-quality cutting tools.


Besides being more commercially available than 440B, 440C is also the hardest of all stainless and heat-resistant steels. 440A offers superior toughness compared to see 440C. There is a free machining version in the 400 martensitic series - 440F.

Product Traceablity

All our stocked products carry a unique bar code while under our care to ensure total product traceability. The functionality of this system can be customised to include our customers' own product codes courtesy of a bespoke supply solution.

Stock Range

We stock 440C martensitic stainless steel in round bars.

440C Stainless Steel
440C Stainless pdf
440C Stock

Product Summary

Product 440C (to AMS 5630)
Type Martensitic Stainless Steel
Availability Round bar
Benefits Higher strength, higher carbon content, moderate wear resistance, the hardest stainless steel after heat-treatment
Applications Bushings, bearings, structural aircraft components, valve parts
Datasheet 440C - Technical Datasheet
Reference Home/ Products/ Stainless Steels/ 440C

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