Bearing SteelsAMS 5898 (Cronidur 30) Bar

A longer wearing martensitic stainless steel with greater corrosion resistance than 440C.

Cronidur 30 is a pressure-nitrided, highly corrosion-resistant martensitic cold work steel. Hardness up to 60 HRc combined with excellent toughness are some of the properties Cronidur 30 has to offer.

Combination of the PESR (Pressure Electro Slag Remelting) process with a forging or rolling technique allow a very high level of cleanliness to be achieved. Cronidur 30 offers polishability and machinability, it also retains stability after heat treatment.

It has excellent corrosion resistance and wear resistance compared to standard cold work steels as well as offering a high tempering resistance up to 500°C.

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Range Enquiry

To enquire about our range or your specific requirements, please contact your local service centre.


Chemical Composition


  • Industry applications: Aerospace and aeronautics, medical, automotive, racing and mechanical engineering, pharmaceutical and food industries.
  • High precision bearings
  • Ball screws
  • Spindles
  • Pumps
  • Valves
  • Indsutrial knives


  • Superior corrosion resistance, higher than 1.2083, 1.4112,1.4301, 1.4571
  • Excellent machinability
  • High dimensional stability after heat treatment
  • Excellent grinding and polishing ability to obtain optimal surface quality
  • High durability by maximum hardness under static and dynamic demands
  • Good wear resistance, higher than 1.4034, 1.2363 or 1.4528
  • Tougher and secondary hardening alternative to all corrosion resistant PM-steels
  • High temper resistance up to 500 °C

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