Titanium alloys comprise a versatile class of biomedical materials. Among them, β- titanium alloy is one of the most promising metallic materials for biomaterial applications thanks to their high mechanical strength, good corrosion resistance and excellent biocompatibility. This study purported to analyze the phase stability in Ti-Nb alloys, evaluating the influence of the Nb content on the microstructure obtained under different heat treatment conditions. To this end, Ti-Nb alloys containing 5 to 35% (wt.%) of Nb were prepared and evaluated. The samples were arc melted and characterized using optical microscopy, transmission electron microscopy and X-ray diffraction. Young’s modulus was evaluated primarily by acoustic techniques.