PLASMA NITRIDING: POPULAR BELIEFS UNMASKED

In the PLASMA 2 configuration, the nitriding process was observed near the ends of the bushes (with the ratio of twice the diameter size) but not in the mid-point of the bushes,, where laboratory analyses have identified the core hardness to drop from 48 to 30-32 HRC: this demonstrates the fact that the hollow cathode phenomenon  originates and develops very fast inside the cavities, making it unmanageable for the temperature to be regulated despite the use of control thermocouples located adjacent to the affected areas.

 In some cases, however, the material melted, not at the inlet of the bushes but just behind the notorious ratio mentioned above, without being able however to penetrate with nitriding inside the entire through diameter.

Without prejudice to the use of simulacra where to allocate the control thermocouples, made with identical geometries and thickness or very similar to the parts to be treated, the hollow cathode remains a very difficult phenomenon to control, despite the fact that the latest systems in our possession are equipped with state-of-the-art electronics and process PLCs; this phenomenon remains the main cause of non-nitriding inside holes (especially deep ones).