Thermodur® E38K Superclean: Toughness Becomes the Standard

In our journey through the steels that have redefined production “normality,” the first protagonist is Thermodur® E38K Superclean. Born to answer extreme toughness requirements, this Cr-Mo-V alloyed hot-work tool steel has established itself as an irreplaceable choice for those operating in die casting and hot plastic deformation. Its strength lies not only in its performance but in the qualitative consistency guaranteed by the remelting process (ESR/ESU), making it a reliable solution for the most complex geometries.

The official technical datasheet of Thermodur® E38K Superclean by Deutsche Edelstahlwerke.

Click here to download the full technical datasheet in PDF (ITA)

Click here to download the full technical datasheet in PDF (DEU)

Thermodur® E38K Superclean is not a common steel. It is a material designed with very low percentages of trace elements , a feature that gives it superior purity and structural homogeneity. These properties translate into concrete operational advantages that have made it a de facto standard for critical applications.

The distinctive feature of E38K is its high toughness. In applications like die casting, where dies undergo severe thermal cycles, the ability to resist crack propagation is fundamental. E38K offers excellent resistance to thermal shocks, drastically reducing the risk of sudden breakage and extending the useful life of the die.

Thanks to the Electro-Slag Remelting (ESR) process , this steel boasts excellent isotropy (uniform properties in all directions) and excellent mirror polishability. This makes it ideal not only for die casting but also for molding high-quality plastics and inserts requiring impeccable surface finishes.

Although born as an innovative steel, its versatility has led it to cover a vast range of industrial uses:

• Die Casting Tools: Ideal for processing light metals , especially for dies of large dimensions and with complex geometries, where toughness is the determining factor.
• Extrusion Dies: Perfect for large and difficult profiles , where hot wear resistance and thermal stability make the difference.
• Hot Stamping: Used for dies and inserts that must maintain high mechanical characteristics even under thermal stress.

For technical managers needing precise parameters, here are some key data extracted from the datasheet:

• Working Hardness: Typically quenched and tempered to 44 – 46 HRC, however, working hardness varies depending on the application; values up to 52 HRC can be obtained.
• Tempering Resistance: Maintains a hardness above 50 HRC even after tempering at 550°C
• Thermal Conductivity: At 350°C, the value stands at 30.0 W/(m K) for the annealed state and 27.3 W/(m K) for the quenched and tempered state, ensuring effective heat dissipation.

Bonomi Acciai believed in the potential of this material from the start. We have spoken about it in depth in the past, analyzing it in various dedicated posts and citing it as a pillar of our catalog in the focus on NADCA Recognized Quality e nella panoramica sul Die Casting Catalog.

Today, we confirm that Thermodur® E38K Superclean is no longer just a “specialty”: it is the norm for those who accept no compromises.