Laser Assisted Size Reduction of Gold (Au) Particles onto a Titanium (Ti) Substrate Surface

Abstract

This paper aims to perform laser assisted size reduction to nanoparticles of gold (Au) sputtered layer on titanium (Ti) base material using an innovative method that could potentially be applied in novel blood contact and thromboresistive devices in the living body, such as ventricular assist devices (VADs). The enrichment of the surface layer of titanium with gold nanoparticles, due to its bioproperties, may contribute to the reduction of inflammatory reactions and infections occurring mainly in the first postoperative period causing implant failure. The possibility of obtaining superficial size reduction and/or bonding of nano gold particles with Ti micromachining by picosecond laser treatment was evaluated. The quantitative assessment of the particles has been made using SEM and are depicted on the histograms, whereby the appropriate number of particles determine the antibacterial properties and health safety. The initial analysis of micromachining process of the prepared material was focused on power-depth dependence by confocal microscopy. The evaluation of gold particles was conducted using scanning electron microscopy (SEM) using SE and QBSD detectors with energy dispersive spectroscopy (EDS) analysis. Attempts to reduce the deposited gold coating to the size of Au nanoparticles and to melt them into titanium matrix using a laser beam have been successfully completed. There seems to be no strict relationship between particle size distribution of gold onto Ti, probably due to too low energy to excite titanium enough, resulting from difference in Ti and Au melting point temperatures. However, the obtained results allow continuation of pilot studies for augmented research and material properties analysis in the future.