Effect of composition on microstructure and compressive mechanical properties in Ti-Cu-Fe-Sn-Nb alloys

Abstract

The microstructure and the compressive mechanical properties of the Ti-Cu-Fe-Sn-Nb alloys are significantly affected by the compositions. When the Cu in the alloys is more than 12 mol% and the Fe more than 10 mol%, the microstructure contains the dendritic bcc β-Ti solid solution, the matrix phase and the eutectic structure. With decreasing the contents of Cu and Fe, the dendritic structure increases in volume fraction, while the matrix phase decreases and the eutectic structure vanishes away. Correspondingly, the yield strength and the Young's modulus decrease, but the plastic strain increases. At the higher contents of Cu and Fe, the alloys exhibit the yield strengths of 1442-1515 MPa and the Young's module of 90-101 GPa, but the small plastic strains. At the lower contents of Cu and Fe, the alloys exhibit the yield strengths of 1050-1321 MPa and the Young's module of 47-76 GPa, which are very attractive for the biomedical applications.