Modification of surface properties of Ti–16Si–4B powder alloy by plasma immersion ion implantation

Results of the surface modification of Ti–16Si–4B powder alloy by nitrogen ion implantation are presented, together with the experimental description of the preparation of that powder by high-energy ball milling and hot pressing. The phase structure, chemical composition and morphology of sample surfaces were observed by utilizing X-ray diffractometer (XRD), atomic force microscope (AFM) and scanning electron microscopy (SEM). A tribological characterization was carried out with a ball-on-disc tribometer and an SEM. Friction coefficient is compared with the one obtained for Ti–6Al–4V alloy and the wear scars characterized by SEM/EDS (energy dispersive spectroscopy). The concentration profile of the detected elements have been investigated using Auger electron spectroscopy (AES) depth profiling. Our results show that a shallow implanted layer of oxygen and nitrogen ions were obtained at the Ti–16Si–4B alloy surface, sufficient to modify slightly its tribological properties.

Research highlights
► Fine reinforcements were produced in a titanium matrix by hot pressing.
► The Ti-16Si-4B powder alloy presents good wear resistance. Plasma immersion ion implantation was applied to the sintered powder slightly changing wear characteristics.
► Characterization of the Ti-16Si-4B is presented in our work and gives important information about its chemistry and wear.