Microstructural and electrochemical properties of TiAlN(Ag,Cu) nanocomposite coatings for medical applications deposited by dc magnetron sputtering

Publication date: Available online 17 February 2020Source: Journal of Alloys and CompoundsAuthor(s): Hernán D. Mejía, Aida M. Echavarría, Jorge A. Calderón, G. Gilberto BejaranoAbstractAISI 420 stainless steel is currently used in the manufacture of surgical and dental instrumentation due to its hardenability, acceptable biocompatibility and resistance to corrosion. However, its resistance to wear is relatively low, and therefore multiple strategies of surface modification are used in order to overcome these drawbacks in the properties of this material when envisaging its use for biomedical applications. In this work, TiAlN coatings doped with Ag and Cu nanoparticles in four different quantities (11 at.% to 20 at.%) were deposited onto 420 steel by DC magnetron sputtering technique. The microstructure, and chemical and phase composition were analyzed by scanning and transmission electron microscopy (SEM/TEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction, while roughness was determined using atomic force microscopy (AFM). The electrochemical behavior of the coatings was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The analysis of the microstructures of the different coatings revealed that the typical columnar structure of the TiAlN matrix is densified as the content of silver and copper increases. The Ag and Cu doping materials are placed in the free spaces between the grain limits of the TiAlN structur...
Source: Journal of Alloys and Compounds - Category: Chemistry Source Type: research