Dissolution of Niobium Particles during Ti-6Al-7Nb Sintering

摘要

The Ti-6Al-7Nb alloy, with α+β microstructure, was commercially developed aiming the replacement of Ti-6Al-4V alloy in the manufacture of surgical implants owing to its largest biocompatibility. The alloy processing by powder metallurgy eases the obtainment of parts with complex geometry and probably, cheaper. Samples of this alloy were obtained from hot uniaxial pressing of the elementary powders, in vacuum. The pressing was carried out in the range 700-1500℃ with compaction pressures of 20MPa. The alloy was characterized by means of scanning electron microscopy, X-ray diffraction, differential thermal analysis (DTA), Vickers microhardness measurements and density. In this work, the elementary powders behavior was investigated during sintering stage. The niobium particles act as β-phase nucleator agent and command the growth of the Widmanstaetten microstructure.