Main Article Content
Ti alloys are widely used in biomedical devices and components, due to their desirable properties such as low modulus biocompatibility and corrosion resistance. Microstructural modification is often performed in order to improve physical, mechanical and tribological properties. This study aims to examine the effect of Nb content on mechanical and tribological behaviour of Hot Isostatic Pressed (HIPed) Ti-6Al-xNb alloys (x= 0, 2, 5 and 7 at. %) for orthopaedics application. Porosity, hardness, Young’s modulus and tribological behaviour of the nanostructured Ti-6Al-7Nb alloys were investigated. The friction and wear tests were carried out under different applied loads of 2, 8 and 16 N, with alumina a-Al2O3 balls, using an Oscillating tribometer. The mechanical characterization indicated that Young’s modulus and hardness increased with increasing Nb content. Addition of Nb led to decrease friction coefficient and wear rate. The lowest values of friction coefficient, volume and wear rate were obtained for samples containing 7 at % of Nb tested under an applied load of 2 N. This enhancement in tribological properties is due to the grain size refinement, low porosity and high relative density of Ti-6Al with 7 at % of Nb.