420 Stainless Steel – Data Sheet, Applications, Hardening

420 is a stainless steel with a high chromium alloy. It is also known under the DIN EN designation X20Cr13 and the EN number 1.4021. The martensitic stainless steel grade shows good hardenability and is used in many industries

Chemical composition – data sheet

The steel is characterized by a high chromium content of at least 12% as well as by a high carbon content.

0.16 – 0.25%≤ 1 %≤ 1.5 %≤ 0.045%≤ 0.03%12 – 14%

Properties of 420

The forgeability of the material is good. The steel can also be magnetised as it has a martensitic structure.

1.4021 is particularly impressive due to its good material properties. It achieves a tensile strength of up to 850 MPa. The yield strength reaches a value of at least 500 MPa. The chromium alloy gives the steel good wear resistance. The chemical resistance is very good in moderately aggressive, chloride-free media. The material should therefore not be used in media containing chloride. The corrosion resistance can be improved by grinding and polishing.

Areas of application

1.4021 is a resilient material with good mechanical properties, which is used in the following areas:

  • Automotive industry
  • medical technology
  • Cutlery industry
  • power engineering
  • mechanical engineering
  • Fasteners
  • Turbine construction, power station construction
  • Chemicals, petrochemicals

Due to its good polishability, 1.4021 is also used in private households. Kitchen equipment and tools are often made from this resilient material. The material is also frequently used for decorative purposes.

Hardening of 420

Due to its good mechanical properties, 420 is used in many applications. However, the steel is prone to intergranular corrosion and is susceptible to chemical stress. The corrosion resistance of the material is good, but shows poorer values compared to V2A steels such as 1.4401 and 1.4301. Hardening of the material is possible, but it does not effectively improve weaknesses.

An alternative solution is a surface hardening process such as our BORINOX® process. Using our hardening technique, the surface layer of the material can be efficiently hardened. This simultaneously increases corrosion resistance, protection against abrasion and wear resistance. At the same time, precipitation of chromium compounds is avoided.