Effect of sintering parameters on microstructure, mechanical properties and electrochemical behavior of Nb-Zr alloy for biomedical applications

Despite the importance of Nb-Zr alloys as candidate materials for biomedical applications, little attention has been given to their processing and the development of new or improved structures. Here, we explore the viability of synthesizing a nano/sub-micron grain structured Nb-Zr alloy through the use of mechanical alloying (MA) and spark-plasma sintering (SPS). The sintered samples were characterized through measurements of densification, Vickers hardness (HV), X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The effect of the SPS parameters on the microstructure and mechanical properties of the sintered alloys was also investigated. Moreover, electrochemical corrosion analyses were performed by a means of a conventional three-electrode cell to assess the corrosion resistance of the developed alloys in Simulated Body Fluids (SBF) medium. A nano/sub-micron grain structured Nb-Zr alloy with an average grain size of between 100 and 300 am was produced using the MA-SPS techniques. A maximum hardness and relative density of 584 HV and 97.9% were achieved, respectively. Moreover, the nano/sub-micron grain structured Nb-Zr alloy exhibited higher corrosion resistance in SBF medium, which makes this alloy is a promising candidate for use in biomedical applications. (C) 2015 Elsevier Ltd. All rights reserved.