Adhesion and structure of c-BN films produced by ion-beam-assisted deposition

Abstract

Ion beam dynamic mixing was performed to improve the adhesion of cubic boron nitride (c-BN) films prepared by ion-beam-assisted deposition. The interface between the c-BN film and the substrate and the adhesion of prepared films were also studied. Ion beam dynamic mixing was performed on silicon wafers and WC-Co coated with TiN by irradiation by ions with energies of 3 and 7 keV and by simultaneous evaporation of boron. c-BN films were then deposited by irradiation by ions with an energy of 0.5 keV. The structure and the adhesion of the coatings were studied by IR absorption spectroscopy, X-ray diffraction, Auger electron spectroscopy, scratch tests and cutting tests. The adhesion of c-BN films was greatly improved by ion beam dynamic mixing. The critical load determined from scratch tests becomes larger with increasing ion beam energy. No cohesive failures of films prepared by ion beam dynamic mixing with an ion beam energy of 7 keV were observed in cutting tests on carbon steels.