Plasma immersion ion implantation of industrial gears

Plasma immersion ion implantation (PIII) has been shown to be an effective surface treatment technique for industrial components, especially those possessing an irregular shape. Gears are widely used for rotary mechanical motion in various industrial machines. Extensive wear can occur on the surfaces due to mechanical contact but the complex shape renders conventional surface modification difficult. In this work, we investigated argon and nitrogen PIII of industrial gears. Rutherford backscattering spectrometry (RBS) was used to determine the implanted ion dose along the gear surface using silicon samples affixed at different positions. The results show that the lateral difference of implanted ion dose is quite large. We have also found a large iron content on the silicon surface at some positions. This corresponds to the degree of sputtering near this position and also reflects the ion implantation angle. Our results indicate that the ion dose along the tooth flank is less than that in other positions on the gear surface, and sputtering is more serious due to the larger ion incident angle as a result of the sheath propagation.