Co-sputtered CuO/TiO2 coatings with varying copper content deposited on Ti6Al4V alloy

Abstract

Abstract In this study, mosaic target material of titanium (Ti) and copper (Cu) was used to deposit CuO/TiO2 coatings on Ti6Al4V alloy. The aim was to examine the change in composition, structure and adhesion of the deposited films on titanium alloy when varying the titanium/copper (20:1, 41:1, 179:1, 418:1 and 837:1) ratio of the target material. The coatings were obtained by sputtering in a glow-discharge in a pure O2 atmosphere for a deposition time of 240 min. All coatings showed homogenous Cu distribution and the film thickness decreased with the reduction of Cu content in the composite target. Cu content in the coatings followed a power function of decrease with reduction of Ti-Cu content in the target while the increase of Ti showed logarithmic dependence. In all coatings, anatase and rutile TiO2 phases were detected whereas Cu atoms participated only in the formation of monoclinic CuO. TiO2-rich coatings demonstrated better adhesion to the Ti6Al4V alloy, whereas the critical loads of CuO-rich films were dependent on coating thickness.