Plasma Nitriding,Plasma Nitriding Steel,Plasma Nitriding tool steel,Plasma NitridingPlasma Nitriding. Another process used for nitriding tool steels is plasma nitriding, also known as ion nitriding. It is
used in the nitriding of high-speed (M and T series), cold work (A and D series), and hot work (H series) tool steels (Ref
5). This process is also a vacuum process, but employs the principle of glow discharge to provide energy for heating and
nitriding (see Fig. 5). Because it relies on electrical energy to dissociate gases, activate surfaces, and to provide energy for
reaction, ordinary nitrogen at pressures in the range 0.1 to 1 kPa (1 to 10 mm Hg) are all that is required for nitriding. In
addition, by adjusting the amount of nitrogen, the surface white layer can be closely controlled or eliminated. As in the
other methods, the cycles are very short. In addition, the temperature range is greatly expanded, to as low as 350 °C (660
°F), because the glow discharge reaction is not dependent on ammonia breakdown as in gas nitriding. This permits greater
flexibility in choice of nitriding temperature so that surface hardness, case depth, and core hardness can be optimized for a
given steel.
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