Wear and friction characteristics of ion-implanted zirconia ceramics

Yttria-tetragonal zirconia polycrystals (Y-TZP) and magnesia-partially stab ilized zirconia (Mg-PSZ) ceramics were implanted with ions of C or a combin ation of Ti + C using a metal vapour vacuum are (MEVVA) ion implanter. Wear and frictional characteristics of ion-implanted Y-TZP and Mg-PSZ ceramic p lates against unimplanted TZP and PSZ pins were investigated using a pin-on -plate reciprocating rig under two levels of load of 1.2 and 2.0 N and an a verage velocity of 0.1 m s(-1). The effects of ion implantation on friction coefficients and wear rates have been explored by comparing the results wi th those of unimplanted self-mated zirconia ceramics. It was found that the friction coefficients of the Ti + C and C ion-implanted ceramics were lowe r than those of the unimplanted ceramics tested under the same conditions b ut the duration of low friction was short. The wear resistance of the C-imp lanted zirconia ceramics was significantly higher during the first 400-600 m of sliding (4 X 10(4)-6 X 10(4) cycles) than that of the unmodified ceram ics, especially at a lower load of 1.3 N. Ti + C ion implantation reduced t he wear of TZP only slightly and did not affect the wear of PSZ ceramics du e to a quite rapid removal of the implanted layer. The C-implanted layer pe rsisted on the ceramic surfaces over a much longer sliding distance. (C) 20 00 Published by Elsevier Science S.A.