Enhancing strength and ductility of pure titanium by interstitial oxygen atoms

Pure titanium is an ideal material for tissue replacements and implant materials for its superior biocompatibility and corrosion resistance, but its limited strength remains a major obstacle to its wide applications. A promising strategy for enhancing the strength is to alloy the pure titanium with oxygen. Herein, we reported an oxygen solid solution strengthening for pure titanium by achieving a titanium-oxygen (Ti-O) alloy using ball milling (BM) and spark plasma sintering (SPS). The effect of oxygen contents, ranging from 0.33 to 2.08 wt%, on the mechanical properties of pure titanium was systematically investigated. Experimental results indicate that the Ti-O alloy with the oxygen content of 1.95 wt% reached an ultrahigh yield strength of 2026 MPa and showed a large ductility of 11.2% in compression. According to the quantified analysis of strengthening mechanisms, solid solute oxygen atoms are responsible for the balance of superior yield strength and ductility of the Ti-O alloys.