Aalberts Surface Technologies (Heat) is part of Aalberts N.V. a global engineering company providing mission critical technologies from more than 150 locations in 30 countries.
The home of hard surfaces
Lab Metallography - polishing and grinding for inspection

Nitriding from specialist metallurgists

With a wide variety of furnaces available, we are capable of handling a comprehensive range of product and batch size, from small series through to 10 Tonnes in weight, and sizes up to 4.2m long and up to 1.6m diameter.
Our staff are expert in advising the characteristics achievable from all material types, from low alloy steels to high quality grade stainless steels and Inconel alloys.

Stress Relieving

The "Stress Relieve" process is typically used to remove residual stresses which have accumulated from earlier manufacturing processes.

Over many years, we have provided Stress Relieving services to clients who want a thorough, and high quality suite of services delivered on their components for wide variety of applications.

Stress Relieving is typically performed on low to medium alloy steels and at a minimum of 30 to 40 degrees Celsius following on from the previous tempering temperature, used after quenching. The materials are heated under a protective non oxidising atmosphere for sufficient time and then slow cooled to avoid formation of excessive thermal stresses.

One of the key advantages of this process is that there is no micro-structural changes during the process.

Post Oxidation

Post oxidation process can be carried out at the end of any Nitriding cycle, or as a stand-alone operation.
A thin (2-3 microns) hard tenacious layer of magnetite is formed blue-black in colour, at typical treatment temperatures of 450-500°

The process is well known on HSS drills and taps, but its benefits are now being recognised in a much wider range of applications.
Also, for many years our Post Oxidation services have proved invaluable for our clients - fewer trips to a contractor, better prices, swifter response - reliable and top quality throughput.

The crucial benefits of the process are:
  • Porous surface- absorbs lubricant, reduces friction.
  • Inherent wear resistance
  • Attractive dark surface finish.
  • Enhanced corrosion resistance- particularly when applied to previously Nitrided surfaces. 
  • Certain steels can pass over 200 hours of salt-spray test per ASTM B117, when treated in this way.