Ferritic Nitrocarburizing (FNC) / Nitridetek is a surface engineering process for the heat treatment of steels and cast irons carried out in the temperature range 550-7400 C (1020-13500 F) using a gaseous nitrogen-bearing atmosphere. The treatments develop iron nitride surface compound layers between 5-50 mm (0.0002″-0.002″) thick, supported by a nitrogen rich diffusion zone in the substrate. Through selection of treatment temperature, time and nitrogen potential of the atmosphere, the structure, composition and hardness of the compound layer and the subsurface diffusion zone are controlled. An innovative oxidation technique, combined with specially formulated aqueous quenchant and organic sealant, are incorporated when corrosion resistance is required.
Wear Resistance & Lubricity
- The high surface hardness of the compound layer, and the presence of surface microporosity capable of retaining lubricant, produces an excellent wear resistant surface.
- Because of the ability to retain oil and the inherent wear resistance, Ferritic Nitrocarburizing (FNC) treated surfaces may operate in contact with one another without the need to employ individual ball bearings.
- Specific hardness profiles indicate the capability of Ferritic Nitrocarburizing (FNC) treated components to resist indentation from point contact surface loading.
- When non-alloyed steels are rapidly cooled after Ferritic Nitrocarburizing (FNC) / Nitridetek treatment, strengthening of thin sections occurs. This results in an increase in both the yield strength of the base material and its fatigue strength.
- Traditional hardening practices may result in distortion and poor dimensional control because of metallurgical phase changes when rapidly quenching from high treatment temperatures. During FNC / Nitridetek treatment these changes do not occur, therefore allowing the treatment of close-tolerance precision parts, especially thin cross section and precision components.
Aesthetic Finish & Corrosion Resistance
- Ferritic Nitrocarburizing (FNC) treatment produces an aesthetically pleasing black surface finish, and combining this with an organic sealant retained in the microporous layer, imparts corrosion resistance superior to that of electroplated components, and comparable to that of medium grades of stainless steel.