Liquid Nitriding QPQ (Salt Bath Nitriding)
Liquid Nitriding (LN) is a subcritical surface enhancement process. It is a commonly used term for the diffusion process that is actually liquid nitrocarburizing.
Black Oxide
Black Oxide is the process of forming a black iron oxide on the surface of ferrous metals, and is most commonly referred to as black oxiding, blackening, oxidizing, gun blueing.