Nitriding as thermochemical treatment on the final material can be used to significantly improve surface and bulk properties.
Nitriding is a gaseous thermochemical treatment that is widely used to improve the surface properties of parts and components made of forging and tool steel. However, extreme bulk strengthening as well as significantly improved wear or surface properties can been obtained by tailoring the design of the final nitriding treatment.
For fundamental understanding, model alloys can be elaborated on lab scale to isolate the effect of one or more specific elements on its behaviour during nitriding. As a result, the alloy compositions can be modified for an optimum response during nitriding by combining the experimental results with thermodynamic calculations.
In addition, in-house models have been developed for nitrogen diffusion and nitride layer formation − allowing OCAS to predict and optimise the nitriding cycles to be applied in order to obtain a specific nitrogen level for a given steel composition.
The translation of this fundamental knowledge into industrial nitriding solutions has already proven some interesting tracks.
Lehrer diagram for pure Fe
Time for through thickness nitriding
OCAS is equipped with both a tube furnace and a reactive annealing simulator, which are able to apply nitriding or other reactive annealing cycles on request. Of course full characterisation of the samples, including TEM, FIB, and XRD is available at OCAS. Our brand new EPMA will give us additional information thanks to enhanced N characterisation. OCAS is also equipped to test a wide range of surface properties.
“The very high N-levels that can be achieved through gaseous nitriding in combination with strong interaction with certain alloying elements result in highly interesting − and relatively unexplored − metallurgy. For a metallurgist, this is very exciting! “
