PIII Treatment of SS Samples Using a Current-Controlled High-Voltage Pulser

Plasma immersion ion implantation (PIII) was conducted in a large volume chamber with a current-controlled high-voltage pulser, to test the vacuum, plasma, and PIII conditions, in a preparation for the treatments of large workpieces or the batch-processing mode. For that purpose, a rugged high-power pulser (10 kW average) based on solid-state moderate voltage pulse system (1 kV) was coupled to a high-voltage transformer (1:22) to feed different loaded sample supports placed in different positions inside the chamber. It was found that the plasma, when produced by a hot filament enhanced glow discharge source, is not uniformly distributed in the chamber but despite that, implantation doses are locally uniform within 10% for 10-15-cm distances, along with the supports. Stainless steel 304 (SS304) -type samples were successfully treated with nitrogen PIII and different tests showed improvements on their mechanical and tribological properties.