Sensitivity of the tensile ductility of powder metallurgy a, a+ß and nearly ß Ti alloys to oxygen

Oxygen is an important issue that affects the powder metallurgy (PM) titanium business in terms of both the cost of production and the resulting mechanical properties. The sensitivity of ductility to oxygen is related to the alloy type. For example, the tensile ductility of PM commercial pure Ti (CP-Ti) dropped from 37.1 to 15.5% with increasing oxygen content to 0.12 wt.% while the ductility of PM Ti-6Al-4V is little affected by the oxygen content until it exceeds about 0.32wt.%. However, there has been limited information about the sensitivity of the near β Ti alloy to oxygen. In this study, pore-free CP-Ti, Ti-6Al-4V and Ti-10V-2Fe-3Al alloys are fabricated from master alloy and Ti powders with different oxygen contents by spark plasma sintering. Their tensile properties are examined with a special emphasis on the influence of oxygen on the tensile ductility of PM Ti-10V-2Fe-3Al.