Liquid nitriding is a subcritical surface enhancement process with one of the longest track records of success of any case hardening technology.
PVD coatings involve the deposition of thin (2-10 microns; 0.0001" – 0.0004") films on the surface of tools and components.
ARCOR® V is default ferritic salt bath nitriding process used by HEF. Typical nitriding temperatures are in the range of 580°C to 590°C - as low as 510°C is possible. This process provides two valuable benefits: a dense epsilon iron nitride compound layer with limited porosity, and processing temperatures that minimize thermal distortion or loss of core hardness of the treated component - without a significant compromise of throughout and productivity. ARCOR® V is also operationally an easier process to control and environmentally friendlier than other liquid nitriding treatments. ARCOR® V is also the best choice for nitrocarburizing of cast iron materials, due to the improved quality of the compound layer.
ARCOR® N is distinctive in that it is an austenitic, rather than a ferritic salt bath nitriding process. ARCOR® N processing includes component immersion in an ionic liquid media at 630°C, to produce a 10-25 micron surface layer of epsilon iron nitride above a nitrogen diffusion layer. ARCOR® N salt bath nitriding delivers both hardness and ductility during its short process cycle. Its ductile compound layer provides outstanding wear and corrosion resistance. When used in conjunction with Corolac post-nitriding impregnation, ARCOR® N corrosion performance on certain steels and component geometries can be up to 1000 hours, per ASTM B117.
ARCOR® C, a.k.a SURSULF® is HEF’s original salt bath nitriding process. ARCOR® C, (SURSULF®), typically operates in the 540°C – 570°C temperature range, and complies with all known nitrocarburizing standards - most notably, SAE Aerospace Material Specification 2753C.
Parts treated with ARCOR® salt bath nitriding effectively resist seizure. The micro-layer inhibits the formation of frictional welding points and assists the running-in of components. The hard, yet ductile surface layers make ARCOR® treated parts compatible with mating surfaces without surface cracking or exfoliation. Finally, the ARCOR® process produces substantial improvements in fatigue resistance.