Effects of carbon and nitrogen ion implantations on surface and tribological properties of Ti–Al–Si–N coatings

Abstract

The post-treatment of ion implantation on hard coatings attracts a great deal of attention because of the improvement in coating surface properties. The present research investigates the effect of nitrogen (N), carbon (C) and carbon followed with nitrogen (CzN) ion implantations on the structural and mechanical properties of the Ti-Al-Si-N coatings. Ion implantations were performed at an energy of 50 keV and different doses. The surface properties of the implanted layer were identified by a variety of analytic techniques, such as cross-sectional transmission electron microscopy, energy dispersive spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and nanoindentation measurement. Additionally, the wear performance of the samples was evaluated by a typical ball on disc tribometer in dry conditions. The results showed that the surface properties depended strongly on the implanted species and doses. In addition, a great improvement in the wear was observed on the samples with the post-treatment process of C and CzN ion implantations. ExperimentalTiAlSiN coatings with a typical thickness of 1?5 mm were deposited onto hardened M2 high speed steel and Si substrates by reactive close field unbalanced magnetron sputtering system (Teer UDP-450) with a high purity of Ti, Al and Si targets. In order to increase the adhesion of the coating, a Ti buffer layer was first deposited. By optimising the deposition conditions, TiAlSiN coatings [39 at-%Ti, 11 at-%Al, 4 at-%Si and 46 at-%N, determined by X-ray Department of Manufacturing Engineering and Engineering Management

Effect of Ti Transition Layer Thickness on the Structure, Mechanical and Adhesion Properties of Ti-DLC Coatings on Aluminum Alloys

“…The residual compressive stress of the Ti-DLC coatings as a function of the Ti transition layer thickness t 0 (μm) is presented in Figure 9 . It can be observed that when t 0 increases, the residual compressive stress decreases sharply from 12.4 GPa at 0 μm to 2.4 GPa at 1.1 μm, which serves as evidence that the residual compressive stress causes the G peak shifting upward to a higher wavenumber as in previous Raman studies [ 40 ]. As we know, this strain is produced by different shrinkage tendencies owing to the direct contact between the coating and Al alloy substrate.…”

Influence of chromium buffer layer on Cr/ta-C composite films

“…Figure 1 shows a typical cross-sectional SEM image of ta-C film. It exhibits that the adhesion strength and hardness of the composite film are favourably improved and hardened by its compact structure 12. Analysis of C, Cr and Si distributions across the film thickness, from the film surface down to the datum surface of the substrate, shows that the elements of C and Cr vary remarkably from layer to layer.…”

Compositionally gradient PVD CrAlSiN films: structural examination and oxidation resistance

“…Various approaches have been investigated in order to achieve extended lifetimes, such as controlling the plastic deformation of coatings by grain refinement according to the Hall-Petch effect, 1 work hardening, 2 solid solution strengthening, 3 precipitation hardening, 1 quenching 4 and surface strengthening by nitriding or nitrocarburizing. 5,6 Among them the most prominent relative method is the deposition of superhard transition metal nitride films, either binary such as TiN and CrN [7][8][9][10] or tailored ternary and quaternary systems, 11,12 due to their exceptional combination of properties, such as hardness, electrical conductivity, resistance to oxidation and refractory character. In particular, Reiter et al 10 reported that the addition of Al to the Cr-N structure increases its decomposition temperature because of the strengthening effect of the Al inclusion in the Cr-N bonds.…”