Adhesive character of wear processes in nitrogen-implanted iron

The friction coefficient and the abrasive wear rate of nitrogen-implanted iron were measured in atmospheres of air, oxygen, argon and vacuum. The results showed that the smallest friction coefficient and wear occur for the sample implanted with a fluence of 1×1017 N2+/cm2. Oxidizing wear was found to be predominant after implantation with a fluence of 3×1017 N2+/cm2 when the increased radiation damage and the defect production were believed to promote intensive oxygen diffusion in the region of interacting mechanical elements. The largest friction coefficient and the largest sample wear were found to occur in an argon atmosphere. Under these conditions it was found impossible to reproduce the oxide layer in the rubbing elements surface layer. As a result, adhesion of interacting elements was increased leading, in turn, to the localised increase of temperature and micro-welding at the points of contact.