The images of two Vickers hardness tester indentations shown below illustrate the difference between a controlled and uncontrolled process. The specimen on the left was produced in a traditional process and the cracking of the surface is indicative of the brittleness of the layer. The one on the right is a product of a Nitreg® process where, in spite of the same hardness, cracks have not formed. The Nitreg® treated component is therefore more resilient with high toughness of the compound layer.

Such superior result can only be achieved by controlling the nitrogen concentration in the substrate and the modern approach is control of nitriding potential (KN). Proper understanding and application of the principles that tie nitriding potential (KN), temperature and time are the cornerstone of the Nitreg® technology. An example of our ability to produce a variety of white layer / diffusion case combinations is shown in the following chart:
Nitrided case combinations – PDF
Gradually the ability to control the nitriding potential is becoming a requirement as set forth by specifications such as AMS 2759/10.
In conclusion, Nitreg® is a modern process, capable of meeting the metallurgical requirements of all nitriding specifications that may have been originally written for salt bath, plasma or traditional gas nitriding