Effect of processing on the structure and wear properties of sputtered zirconium oxide thin films

Thin films of zirconium oxide were deposited on injection molded stainless-steel substrates via direct sputtering using yttria-stabilized zirconia target under controlled temperature and environment conditions. The films thus obtained were characterized for their structure, grain size and wear properties. The deposited films, less than 1 μm in thickness, were found to have a predominantly tetragonal structure with grain size of about 5 nm. The films were heat treated to study the stability of phases and changes in tribological properties. The grain size was found to increase only slightly with increasing heat treatment time at 650 °C. Finally, it has been shown that thin-film zirconia coatings with stable structure, good adhesion and very low friction coefficient could be produced using appropriate sputtering and post heat treatment parameters.