Martensitic Stainless Steels

Martensitic Grades Stocked:






* Materials where applicable are supplied in accordance with NACE MR0175

Rounds: 3mm dia. to 520mm dia

Rectangular: 50.8mm x 12.7mm to 240mm x 75mm

Square: 12.7mm Sq. to 50.8mm Sq


  • High strength
  • Good hardness & toughness
  • Moderate corrosion resistance
  • Magnetic
  • Poor weldability

Martensitic stainless steels are low carbon steels built around the Type 410 composition of Iron, 12% to 15% Chromium, and 0.08% to 0.50% Carbon. They can be heat treated and hardened and are often tempered to give good hardness and high toughness. Untempered martensite is low in toughness and therefore brittle. Type 431 has the addition of Nickel to further improve the properties. Martensitic steels have poor corrosion resistance compared to austenitic steels.


Martensitic stainless steel is often used when hardness is critical, such is in knives, where surface hardness creates a sharper blade, also for medical tools (scalpels, razors and internal clamps), gears, valves, pumps, shafts, bearings, turbine parts.

The metallurgy of these steels can be complex and if you need any help concerning usage, heat treatment etc, please do consult our in-house metallurgist for advice specific to your needs.

William Innes, 01226 766766