Compositional library of β Ti-Nb-Zr alloy coatings applied to biomedical prostheses

Abstract

The β Ti-based alloys have attracted considerable interest as biomedical materials due to their unique characteristics, such as excellent biocompatibility, low elastic modulus, low density, and corrosion and wear resistances in biological environment. Ti, Nb, and Zr are non-toxic and non-allergenic biocompatible metals, and the addition of Nb and Zr to Ti favors the mechanical compatibility between the alloy and the bone. The addition of Nb to Ti yields to the stabilization of the β phase, and the addition of Zr to the Ti-Nb system increases the β stabilizing effect. However, the ideal amounts of the constituent elements in the Ti-Nb-Zr ternary system are uncertain. Combinatorial strategies allow for the production and characterization of many alloys simultaneously, and magnetron sputtering has been used to generate compositional libraries for ternary thin films and coatings. In this study, Ti-Nb-Zr ternary alloy coatings were deposited by magnetron sputtering on a Si (100) wafer substrate. The Ti, Nb, and Zr targets were positioned in a triangular configuration below the Si substrate. A composition gradient was formed over all the substrate area. Chemical, structural, and morphological analyses were performed by energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and atomic force microscopy.