Among the biomedical alloys, titanium based alloys are currently the best solution for implantation as a result of their low levels of toxicity. To improve mechanical properties, a series of chemical compositions of some titanium alloys have been studied over the past 15 years, to provide elasticity values as close as possible to bone. The paper presents the main mechanical and microstructural characteristics of Ti-Nb-Ta-Zr alloys compared to other titanium brands. It was found that in the absence of heat treatments, the highest hardness values (437HV1) were obtained for the Ti15Nb7.6Ta8Zr alloy, and the lowest hardness value (259 HV1) was obtained for the Ti98.4 alloy.

Titanium is one of the most appreciated biocompatible materials, as it possesses both good mechanical characteristics but also high corrosion resistance in contact with biological environments. Initially, Ti-6Al-4V trade mark was used for the manufacture of implantable medical devices, being usually selected for making aerospace structures. Over time, it has been found that aluminum and vanadium are not elements with acceptable biocompatibility, metallic ions being found either dissolved or accumulated in certain areas adjacent to the implants. Therefore, the development of titanium alloys dedicated to biomedical applications is still highly required. The effects of chemical elements (Al, Fe and Mn) on the microstructure and microhardness of titanium alloys for medical applications are analyzed in the paper. The experimental alloys were obtained by melting of raw materials in an argon inert atmosphere of the VAR equipment, using high purity metallic elements. Has been developed Ti-base alloys that contain different concentration of 11 to 18 wt. % Al, 2 to 7wt. % Fe and 6 wt. % Mn for highlighting the effects of these elements on the micro-structure and microhardness of titanium alloys. SEM and EDAX analysis revealed the microstructure and microhardness changes occurred by using of alpha stabilizing elements (Al) or beta stabilizers (Fe, Mn).