Nitriding, deeper: why this course exists

Gas nitriding is controlled by the ratio of ammonia to hydrogen in the retort, expressed as the nitriding potential Kn. Plasma is controlled by the nitrogen-to-hydrogen gas ratio and the discharge parameters. Salt-bath chemistry sets the carbon and nitrogen activity of the melt. The atmosphere variable decides whether the compound layer is ε-dominant, γ'-dominant, mixed, or absent, and whether the vendor knows which they grew. A vendor running open-loop ammonia at fixed flow produces whatever the retort dissociates that day, not whatever the print called for.