Stainless Steel, Martensitic1.4057 (431) Bar

A high chromium, low nickel high hardenability martensitic stainless steel.

1.4057 (Type 431) is a hardenable martensitic stainless steel alloy which combines high tensile strength and torsional strength. The material is well suited to shaft manufacture due to these characteristics.

Of all the stainless steels, 1.4057 it has one of the best combinations of high strength, corrosion resistance, and good impact toughness.

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Product FormConditionImperial SizesMetric Sizes
Round BarQT80018" - 6"4.0mm - 30.0mm
Round BarCondition P18" - 6"4.0mm - 30.0mm
If you do not see what you are looking for, please contact your local service centre with your specific requirements.

Related Specifications

  • DIN 1.4057
  • X17CrNi16-2
  • AISI 431
  • BS431S29


Chemical Composition


  • Marine systems
  • Pump & propeller shafts
  • Outboard motor driveshafts
  • Valve stems
  • Aircraft components
  • Axles
  • Fittings
  • Bolts & nuts


  • Considerable resistance to saltwater corrosion
  • Heat treatable martensitic stainless steel
  • High tensile and torsional strength and is well suited to shaft manufacture.
  • Welding is poor and cannot be easily cold worked

Additional Information

Heat Treatment

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