Plasma processing of AISI 304 stainless steel using radio frequency hollow cathode discharge

The plasma source is very important in plasma processes as it determines the plasma characteristics including plasma density, electron temperature, and plasma distribution. A radio frequency (RF) hollow cathode plasma source boasts a small size and can deliver a high local plasma density while the discharge can be easily ignited. In this work, we treat AISI 304 stainless steels using this source and determine the effects of the discharge parameters on the surface properties of the treated materials including hardness, wear resistance, corrosion resistance, and other properties. Our results show an optimal process window (gas flow, sample bias, and RF power) that delivers the best tribological properties and corrosion resistance. The plasma processes using this source are relatively complicated as no new phases can be detected in the treated materials. The process is believed to be a deposition-dominant one due to sputtering of the nozzle of the hollow cathode.