Nitriding is the process of infiltration of nitrogen atoms into the surface layer of steel to improve surface hardness and abrasion resistance, as well as to improve fatigue strength and corrosion resistance.

It is the use of ammonia in the heating of the decomposition of the active nitrogen atoms, after the steel absorption on the surface of the nitriding layer, while the centripetal part of the diffusion.

Nitriding is usually carried out using specialized equipment or pit-type carburizing furnaces. Applicable to all kinds of high-speed transmission precision gears, machine tool spindle (such as boring bar, grinder spindle), high-speed diesel engine crankshaft, valves and so on.