Investigation of microstructural, mechanical, antibacterial and cytotoxic properties of Ti-nb based alloys produced by mechanical alloying method

In this research, new generation titanium alloys as biomaterials were produced by mechanical alloying with the addition of non-toxic elements such as Nb, Sn, Ta, Hf and Zr. Mechanical alloying experiments were carried out at room temperature in a high energy ball milling for 8 hours. After alloying procedures the as-milled powders were consolidated using an uniaxial pressing and sintered at 1150C for 2 hours followed by microstructural (X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive Spectrum (EDS)), mechanical (hardness and elastic modulus) and biological (antibacterial and cytotoxic tests) characterizations. The results obtained from XRD and EDS analyses showed α - Ti, β - Ti and TiC phases in the sintered alloys. Hardness tests taken from the sintered samples revealed a wide range values between 340 and 1322 HV depending on the alloy compositions and TiC phases. The density investigations showed that the sintered alloys had relatively low density resulting from high porosity varying between 0.87 - 12.37 %. The elastic modulus of the sintered samples were found between 48.3 to 130 GPa as a function of added elements, some of which was close to the elastic modulus of bone. Antibacterial and cytotoxic tests results showed that the synthesized alloys possessed good antibacterial properties and were not toxic for body. Overall, the obtained results from this study have shown that the developed alloys have the potential as a new generation biomaterials.