X15TN® - 1.4123 - AISI 420 MOD - X40CrMoVN16-2


  • France
  • FR


Grade 1.4123 (AISI 420 MOD), an alternative to CRONIDUR 30®, is a very high hardness martensitic stainless steel with good abrasion resistance and a corrosion resistance far superior to that of the 17% Cr to 1% C range (type 440C). It is manufactured using ESR remelting to optimise fatigue life and corrosion resistance. Stainless offers the X15TN® grade, developed by Aubert & Duval.

Stainless has a range of sizes in stock to suit your application requirements. This product can also be made to measure or cut into slabs by our service centres.


Main applications

Due to its good resistance to corrosion and its high hardness in the treated state (>58HRC), the grade is used in particular in the manufacture of instruments for the medical sector (screwdrivers, drills, cutting guides, etc.), in bearings and in the cutlery sector.



The elaboration processes associated with the transformation processes make it possible to obtain a homogeneous microstructure with a homogeneous distribution of carbides. In the processed state, the microstructure consists of martensite and undissolved carbides.

X15TN® - 1.4123 - AISI 420MOD - X40CrMoVN16-2


The grade can be hot forged in the temperature range 1000/1200°C.


Polishable grade in the treated condition with a structure consisting of martensite and carbides. The high level of cleanliness increases the polishability of this grade. Laser marking can lead to a local decrease in corrosion resistance, especially in the case of overheating.

Corrosion resistance

The grade contains molybdenum and nitrogen, which improve the resistance to generalized or pitting corrosion in the treated condition. Its resistance to corrosion in non-chloride environments is enhanced by polished, pickled and passivated surfaces.

The corrosion resistance is strongly degraded in the annealed condition or after welding, which is not recommended.

Standard Sizes

  • Round bars annealed (Condition A) – Surface ground or peeled depending on the diameter
  • Flat bars made to measure in the annealed condition (consult us)
  • Other formats: please contact us

Stainless has a wide range of stainless steels from the world's leading producers.


Available formats: Strips, tubes, bars, wires, flat bars, forged blocks, powders
Other formats are available from stock or on order. Contact us.

Austenitic stainless steels

316L – 1.4404

304 – 1.4301


Martensitic stainless steels for tempering (type QT)

X15TN® – 1.4123


Martensitic steels with structural hardening (type PH)

17-4PH -1.4542

Custom® 455 – MX455 – 1.4543
Custom® 465 – 1.4614

Remelted austenitic stainless steels for prostheses and implants

M30NW® – 1.4472
316LVM – 1.4441