During the last decade, rare and high melting point metals (Nb, Ta and Zr) have been widely used as alloying elements for biomedical titanium alloys, as pointed out in the TNZT-O (Ti-36Nb-2Ta-3Zr-0,3O wt.%) composition developed by Saito, 2003. These elements, however, are costly and difficult to process. The combination of low cost metals, such as Mn, Fe or Sn, with classical beta stabilizer elements, such as Nb, is an important vector for the development of new biomedical alloys, with desirable mechanical properties for bioimplants. This work deals with the study of new Ti-Nb-Zr-Fe alloys, concerning phase transformations, aging heat treatments and mechanical properties. Eight alloys of Ti-Nb-Fe and Ti-Nb-Fe-Zr systems will be prepared via arc melting, under controlled atmosphere. The samples will be homogenized at temperatures above beta transus, hot rolled and submitted to different heat treatments, varying cooling rate, temperature and time. Then, the samples will be analyzed by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy and transmission electron microscopy. The aim of this work is to understand the influence of iron as either tertiary or quaternary element, partially substituting Nb, on the phase transformation events and mechanical properties of these novel alloys. Their compositions were determined with aid of the electronic parameters proposed by Morinaga, 1998. By the end of this work, it is expected to develop an optimal composition of the Ti-Nb-Zr-Fe system, with relative low cost and excellent mechanical properties.
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