Ferritic Nitrocarburizing

Process

AMS 2759/12
Ferritic Nitrocarburizing is a case hardening process that is used to produce a hard, wear resistant surface. Despite the name, the process is a modified form of nitriding, not carburizing.  However, both processes introduce nitrogen and carbon in the ferritic state.  The case hardening process diffuses nitrogen and carbon into ferrous metals at sub-critical temperatures.  Because of the low process temperature, little size change or shape distortion occurs allowing this process to be successfully applied to a wider variety of finished parts.  The process is more commonly applied to law alloy steels, mild steels and cast irons, but can also be applied to any steel which is thermally stable at the treatment temperature.   Benefits include:  wear resistance, scuffing/seizure Resistance, improved fatigue, improved corrosion resistance, good surface finish, and minimal shape distortion.

Specifications

Because of the low processing temperature, steel and other ferrous alloys are still in the ferritic phase when the case hardening process takes place.  Ferritic Nitrocarburizing creates a shallow surface layer of epsilon iron nitride compound that typically has a hardness ranging between 58-65 HRC.  This compound increases the base materials resistance to corrosion.
Typical processing temperatures range from 977F – 1157F (525C – 625C)

Applications

Gears, hydraulic piston rods, cams