Strong-yet-ductile Ti−Zr alloys through high concentration of oxygen strengthening

Abstract

Abstract Ti−Zr alloys (oxygen content 0.42−0.54 wt.%) were prepared via powder metallurgy and hot working. The results indicate that the Ti−Zr alloys exhibit Zr-rich and Zr-lean areas with the same α-phase structure, and the Zr-rich area shows a slightly higher oxygen content and a much finer grain size. The Ti−Zr alloys present a good combination of high strength (σs=700−900 MPa) and total elongation (>20%), and solid solution strengthening of oxygen plays a major role. Zr does not influence much the oxygen-induced brittleness due to its high structural similarity to Ti. Therefore, the high value of 0.54 wt.% is still within the critical oxygen content for the ductile-to-brittle transition of Ti and does not degrade the ductility.