The Reduction of Adhesion by Ion Implantation
The effects of boron and argon ion implantation on the tribological characteristics of SUS440C stainless steel, sliding against a SUS440C ball (unimplanted) were investigated at room temperature using a friction test apparatus employing a ball-plate geometry in the absence of a lubricant. Wear performance was estimated using a profilometer tracing of the specimen wear track. Boron implantation reduced both the friction and wear of SUS440C. The friction coefficient of SUS440C was reduced from 0.75 to 0.15. SEM observations of wear track topography suggest that the reduction of the friction coefficient can be attributed to reduced adhesion due to boron implantation. The friction coefficient of the boron implanted layer decreased with an increase in the total ion dose. Argon implantation was carried out to distinguish the effects of implantation from the influence of contamination. Argon implantation increased the friction coefficient from 0.8 to 1.0 in contrast with boron implantation.