Liquid Nitriding Process

Basic Process Steps for Liquid Nitriding:

CLIN Process Steps
Scope
Description
Degreasing/Rinsing
Remove oils, and other particulates from the surfaces of the parts
Preheating
Maintain a stable temperature in the nitrocarburizing melt
Nitrocarburizing
Nitride layer formation on component surface. Using HEF’s ARCOR® and MELONITE® & TUFFTRIDE® / (TENIFER®) Nitriding salts
The hard nitride layer provides wear resistance. The diffusion region underneath the nitride layer provides improved fatigue life
Oxidizing*
Oxide layer formation on component surface. Using HEF’s Oxynit® and other trademarked Oxidizing salts
Oxynit® is a post-nitrocarburizing molten salt bath treatment that provides added corrosion protection by oxidizing the porous zone of the iron nitride compound layer into stable iron oxides (Fe3O4) – also called magnetite. Oxide layer also provides a black aesthetic appearance.
Cooling/Cleaning
Remove salt from the surface of the parts
Mechanical finishing*
Smooth surface, low roughness (no lower than before treatment), friction properties
HEF expertise:
Blast finishing
Mass finishing
Centerless polishing
Surface Impregnation*
Additional corrosion resistance;
improved run-in behavior;
deep-black appearance
HEF impregnation using:
Corolac® (dry appearance)
Corofluide® (oily appearance)
*optional


The LN process is carried out in equipment manufactured by HEF and customized to the nature of the applications under consideration – the size and shape of components to be nitrided; the throughput rate required; process steps required to achieve the desired nitriding specifications; and environmental considerations. A schematic view of a typical ARCOR® process line is shown below:

Liquid Nitriding

Liquid nitriding is a subcritical surface enhancement process with one of the longest track records of success of any case hardening technology.

Engineered Bushings

HEF bushings are recognized worldwide for their excellent frictional and anti-seizure properties, and ability to withstand high loads.