Deposition of soft self-lubricant metals on steel: Improved adhesion by ion beam and tests on non planar geometry

In this work a comparison between conventional Physical Vapour Deposition (PVD) and Ion Beam Assisted Deposition (IBAD) coatings is presented. Silver coatings on several substrates have been deposited by using IBAD. The conventional PVD was performed by a thermal evaporation. We show that the ion–beam irradiation is relevant both for surface pre-treatment step (surface cleaning) and to create mixing between substrate and film. The variable parameters were deposition rate, ion energy, and ion current density: they have been varied in a wide range of values and the results have been correlated to them. Scanning Electron Microscopy and X-ray spectroscopy have been used to investigate morphology, thickness, and roughness of the deposited films. Scratch test has been used to measure the adhesion for the different experimental conditions. Moreover, non planar geometries have been tested in order to extend the successful use of the technique to different applied fields. A relevant example of industrial technological transfer is illustrated.