Effects of Ta content on phase transformation in selective laser melting processed Ti-13Nb-13Zr alloy and its correlation with elastic properties

Abstract

The phase transformation (β→ω and ω→α+β) and its correlation with the elastic properties of the selective laser melting (SLM) processed Ti-13Nb-13Zr-[0–8]Ta (wt.%) alloys were investigated. Analysis of the ω phase formation revealed that when the content of Ta is less than 6%, the formation of ω phase increases with the increase of Ta content in the alloys, while the high content of Ta (8 wt%) suppresses the ω phase formation. The elastic modulus of the alloys increases first and then decreases with the increase of Ta content due to the subsequent changes in the amount of ω phase. However, the ω phase is decomposed into α and β phases after solution treated and the elastic modulus of the alloys is decreased with the increase of Ta. Furthermore, the orientation relationship of O’ phase with β phase was discussed by black field transmission electron microscopy and selected-area electron diffraction.