Characterizing solute hydrogen and hydrides in pure and alloyed titanium at the atomic scale

TL;DR

This study uses advanced microscopy techniques to analyze hydrogen distribution and hydride formation in pure and alloyed titanium, revealing specific conditions under which hydrides form or are absent, impacting titanium's mechanical properties.

Contribution

It provides detailed atomic-scale characterization of hydrogen and hydrides in titanium alloys, highlighting the effects of alloying elements and microstructure on hydride formation.

Findings

Hydrides form along grain and phase boundaries in pure Ti and certain alloys.

No hydrides observed in alloys with Al or quenched-in Mo.

Hydride formation influenced by alloy composition and microstructure.

Abstract

Ti has a high affinity for hydrogen and is a typical hydride formers. Ti-hydride are brittle phases which probably cause premature failure of Ti-alloys. Here, we used atom probe tomography and electron microscopy to investigate the hydrogen distribution in a set of specimens of commercially pure Ti, model and commercial Ti-alloys. Although likely partly introduced during specimen preparation with the focused-ion beam, we show formation of Ti-hydrides along {\alpha} grain boundaries and {\alpha}/\b{eta} phase boundaries in commercial pure Ti and {\alpha}+\b{eta} binary model alloys. No hydrides are observed in the {\alpha} phase in alloys with Al addition or quenched-in Mo supersaturation.