TRIBOLOGICAL PROPERTIES OF ALUMINUM MODIFIED WITH NITROGEN ION-IMPLANTATION AND PLASMA TREATMENT

Surface modification of Al by a combination of ion implantation and plasma treatment has been investigated from the tribological viewpoint. Nitrogen ions were implanted into pure Al specimens at 90 keV and then ion-nitrided at a few kV for 6 h. The wear test was carried out using a wheel-on-plate-type testing machine. It was shown that these treatments reduce the friction coefficient, the wear rate and increase the hardness. The surface of the Al specimen was observed by optical microscopy and SEM. A lot of blisters emerged on the surface of the treated Al specimen. The TEM observation revealed the detailed surface structure of the modified layer. These results suggest that the combination of the treatments is effective for the modification of tribological properties of the Al surface.