Achieving high strength and low Young's modulus in martensitic Ti-Nb-O alloys

摘要

In this study, the effects of oxygen addition on the phase formation and mechanical behavior of martensitic TiNb-O alloys with relatively low Nb contents were evaluated. The oxygen content did not change the phases formed after solution followed by water quenching and samples' microstructures were mainly composed of orthorhombic alpha '' martensite. The presence of retained beta and omega ath phases was identified in alloys with Nb content equal or higher than 20 wt%. Hardness and compressive strength increased with oxygen addition, whereas the Nb content had a minor influence. The Young's modulus was found to be significantly affected by Nb but not by oxygen. Accordingly, it was possible to increase the mechanical strength of the alloys while maintaining their elastic moduli at a low level.