Nano-scale structural non-uniformities in gum like Ti-24Nb-4Zr-8Sn metastable β-Ti alloy

Abstract

Phase instabilities in a recently developed gum like alloy, Ti-24Nb-4Zr-8Sn (Ti2448), were investigated using conventional and aberration-corrected scanning/transmission electron microscopy. Athermal ω (hexagonal) and O′ (orthorhombic) phases were found to be present in the alloy following solution treatment. A partial collapse of {111}β atom planes was observed in the ω phase, and a shuffle of every other {011}β atom planes along 01¯1β was observed in the O′ phase particle. The presence of both the ω and O′ phases in Ti2448 may influence the transition behavior under loading and may have significant impact on its mechanical properties.