Study on micro droplet reduction on tin coated biomedical TI-13ZR-13NB alloy

Abstract

Cathodic arc physical vapor deposition (CAPVD) is one of the physical Vapor deposition (PVD) techniques used to coat titanium nitride (TiN) on biomedical implants due to its good adhesion and high evaporation rate. However, this technique emits micro droplets which have can detrimental effect on the coating performance. Previous studies reported that micro droplets can be controlled through proper deposition parameters. In this paper, the PVD coating was performed on the Ti-13Zr-13Nb biomedical alloy with different substrate temperatures. Scanning electron microscopy (SEM) was used to characterized the surface morphology and coating thickness while X-Ray Diffraction (XRD was employed to evaluate the crystal phase of the coated substrates. Image analysis software was used to quantify micro droplets counts. The results show that higher substrate temperature able to decrease a significant amount of micro droplets and concurrently increase the thickness of TiN coating. A mixed crystal planes of (111) and (200) are obtained on the coated substrates at this setting which exhibits denser structure as compared to substrates coated at lower substrate temperature.