Effect of the high doze of N+(1018 cm–2) ions implantation into the (TiHfZrVNbTa)N nanostructured coating on its microstructure, elemental and phase compositions, and physico-mechanical properties

Abstract

Structure and properties of (TiHfZrVNbTa)N nanostructured multicomponent coatings implanted with a very high (10¹⁸ cm^–2) dose of N⁺ions have been studied. As a result of the implantation a multilayer structure has been formed in the surface layer of the coating. The structure is composed of amorphous, nanocrystalline (disperse) and nanostructured (with the initial sizes) nanolayers. In the depth of the coating two phases (with the fcc and hcp structures) having a small volume content are formed. The nitrogen concentration near the surface attains 90 at % and then decreases with the depth. In the initial state after the deposition the coating nanohardness values are from 27 to 34 GPa depending on the conditions of the deposition. As a result of the implantation the hardness is decreased approximately by the depth of the projective ions range, i.e., to 12 GPa and then increases with the depth to 23 GPa. The investigations were conducted using the Rutherford backscattering, scanning electron microscopy with the microanalysis, high resolution electron microscopy (with local microanalysis), X-ray diffraction, nanoindentation, and wear tests.