Gaseous Nitrocarburizing

Standard – UNI 5478
Typical Materials – 42CrMo4, 39NiCrMo3, 41CrAlMo7, C40, etc.
Metallurgical Characteristics Achievable – Surface hardness varies depending on the material and pre-treatment hardness, ranging between 450-1200HV. Effective nitriding depth: 0.10-0.60mm

Gas nitriding is typically applied to finished parts at the end of all mechanical processes. In some cases, depending on the application and the degree of finish, a subsequent lapping process may be necessary.

Nitriding provides components with high surface hardness without affecting core mechanical properties. Additionally, it offers high wear and corrosion resistance. This process is widely used in the automotive industry, particularly for transmission shafts, where fatigue resistance is significantly increased.

The process involves heating the components to temperatures below austenitization, typically between 510-550°C, in a controlled atmosphere that facilitates the surface diffusion of nitrogen. By adjusting the exposure time, the required depth can be controlled according to the design specifications. Due to the slow diffusion rate, the achievable depths are much lower than those obtained with thermochemical processes like carburizing. After nitriding, the components are slowly cooled within the furnace to ambient temperature.

The low processing temperatures greatly minimize deformations, especially if the process is preceded by pre-treatment hardening and/or stabilizations at temperatures of at least 570°C.