METHOD FOR ENHANCING THE PROPERTIES OF THE SURFACE OF 73TI-20ZR-5TA-2AG ALLOY BY DEPOSITION OF AG MICROSTRUCTURES

摘要

The invention relates to a process of electrochemical deposition of a layer of Ag microparticles on the surface of 73Ti-20Zr-5Ta-2Ag alloy, said alloy being meant to be used in the medical field for manufacturing metal implants with increased corrosion resistance, increased biocompatibility and low rugosity. According to the invention, the process has the following stages: cleaning the metal discs of 73Ti-20Zr-5Ta-2Ag alloy, used as electrodes, by polishing with emery paper-grade 1200, in order to remove the native oxide layer from their surface, cleaning the discs with water and ethanol for 10 min each, in the ultrasonication bath, treating the disc surface by immersion in a solution of 10M Triton X-100 and, without allowing the discs to dry, placing an aqueous solution with a content of 2.5% polystyrene nanospheres with a diameter of 100 nm on their surface by the spin coating technique, at 3200 rpm, after uniformly spreading the solution of polystyrene nanospheres, the discs are dried at ambient temperature, an electrolyte being prepared with the following composition, 0.5 mM AgNOand 50 mM NaNO, of which Ag nanoparticles are obtained, a system with three electrodes being used for the electrochemical deposition: the working electrode formed of metal discs coated with polystyrene nanospheres, the reference electrode of Ag/AgCl and the auxiliary electrode of platinum, the electrochemical method used being the pulsed potential deposition with an applied potential of 350 mV vs Ag/AgCl, with 250 pulses, on the total experimental duration of 10 s, a potentiostat Autolab 302N being used, and after the electrochemical deposition the metal discs being immersed in toluene for two hours for removing the polystyrene nanospheres and finally the samples being washed with deionized water and left to dry at the room temperature.