Amorphization Effects on Pure Titanium Using C+, O+ and Cr+ Ion Implantation

Abstract

In this work, the influence of the amorphization effect of C +, O + and Cr +, implantation on the friction and wettability properties of pure titanium (grade 2) has been studied. Doses from 1×1017 to 5×1017 ions cm-2 at multiple energies of 50 to 190 keV have been used. Additionally, pin-on-disk tribological tests using Ultra-High-Molecular-Weight-Polyethylene (UHMWPE) pins under lubricated conditions and wettability measurements of implanted and unimplanted titanium samples were carried out. We found, that the more suitable material for the wettability and hence wear resistance is C + implanted titanium, because of its higher surface energy than the unimplanted titanium corresponding energy. Friction tests on monoenergetic 180 keV C + and O + modified titanium with 1×1017 ions cm-2 have showed an essentially reduced friction compared to samples implanted with the same dose but at multiple energies. A reduction of the wettability by about 7% and the friction coefficient by about 18% was observed for carbon implanted titanium with a dose of 1×1017 C + cm-2; this effect corresponds to a good correlation between wettability and friction coefficient after C + implantation in titanium. It was concluded that the reduction of the friction coefficient with monoenergetic C + implanted titanium is 3.7 times lower compared with those of pure titanium. This important result could extend the average lifetime of orthopaedic components of approximately 2 orders of magnitude.