Antibacteria and anti-wear TaN–(Ag,Cu) nanocomposite thin films deposited on polyether ether ketone

Abstract

Hard TaN–(Ag,Cu) nanocomposite films were deposited on PEEK (polyether ether ketone) substrates using reactive co-sputtering. The films were then annealed using RTA (Rapid Thermal Annealing) at 200°C to induce the nucleation and growth of soft metal particles in the TaN matrix and on the surface of the films. After examining the surface morphologies, structures, and mechanical properties of the samples, they were tested for their tribological properties under a normal load of 1N or 5N. It was found that the samples' tribological properties were much improved compared to uncoated PEEK, even though the substrate is relatively soft. This was especially apparent for heavier loads. Apparently, the solid lubricants (i.e., Ag and Cu particles) that emerged on coating's surface during the annealing process reduced the frictional force and wear rate of PEEK. These results were similar to those that were obtained using tool steel substrates. The coated samples were also tested for their anti-bacterial properties using Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria. It was found that the anti-bacterial efficiency of these samples was significant against both E. coli and S. aureus, even though the deposited samples were annealed through RTA at the relatively low temperature of 200°C. There was no peeling found between coatings and PEEK substrates after tribological and scratch testings.