1.4021 - X20Cr13 – AISI 420 – SAE 420 – ASTM F899


Grade 1.4021 is a martensitic stainless steel that can reach a hardness of about 46 HRC after hardening and tempering and has high abrasion resistance with moderate corrosion resistance. Its production is usually carried out in air (EAF+AOD).

Stainless has various formats in stock to best meet your processing requirements. This product can also be made to measure or cut into blanks by our service centers.

Main applications

Due to its corrosion resistance and hardness in the treated state (46HRC), the grade is used especially in the manufacture of instruments for medicine, in the food industry or even in the field of cutlery.


The manufacturing processes in combination with the processing procedures allow a homogeneous microstructure with a homogeneous distribution of carbides. In the processed state, the microstructure consists of martensite and partially dissolved carbides :




The grade can be hot forged in the temperature range 1000/1100°C.


Machining of this grade does not cause any difficulties in the QT700 or QT800 states. The grade is polishable in the treated condition and has a microstructure consisting of martensite and carbides. Laser marking may cause a localized reduction in corrosion resistance, especially when overheated.

Typical heat treatments

With a targeted hardness ≥ 45HRC
  • Heating 950/1050°C
  • Quenching Oil or gas under pressure
  • Tempering from 180°C /2h – It is not advisable to temper between 400 and 600°C (embrittlement zone).

Corrosion resistance

The grade contains little chromium and no molybdenum, which limits corrosion resistance. Corrosion resistance is better when the surfaces are polished, pickled and passivated. Corrosion resistance is severely compromised in the annealed condition or after welding, which is still discouraged.

Standard Sizes

  • Round bars in annealed condition (Condition A) or pretreated QT 700 or QT 800 – Surface peeled or ground depending on diameter
  • Flat bars made to measure in annealed condition (please request) – Forged blocks – Sheets
  • Other sizes: please request