First experimental evidence of oxygen ordering in dilute titanium-oxygen alloys

Régis Poulain (1) , Stéphanie Delannoy (1) , Ivan Guillot , Fabienne Amann (1) , Raphaelle Guillou (2) , Sylvie Lartigue-Korinek (3) , Dominique Thiaudière (4) , Jean-Luc Bechade (5) , Emmanuel Clouet (5) , Frédéric Prima (1)

1 ENSCP - Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL
2 LA2M - Laboratoire d'Analyse Microstructurale des Matériaux
3 UPEC UP12 - Université Paris-Est Créteil Val-de-Marne - Paris 12
4 SSOLEIL - Synchrotron SOLEIL
5 SRMP - Service de recherches de métallurgie physique

Small addition of oxygen is currently used to improve the mechanical properties of titanium. It has been thought, until now, that oxygen fully dissolves in the titanium matrix, thus leading to a solid solution. However, we show here, with transmission electronic microscopy and X-ray diffraction, that oxygen can also form ordered precipitates with a Ti$_6$ O-type structure, even for a concentration as low as 0.15 wt% O. The ordered precipitates found in a series of pure binary Ti-O alloys are also visible in commercially pure titanium, including grades 2 and 4, two compositions widely used for technological applications.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Régis Poulain, Stéphanie Delannoy, Ivan Guillot, Fabienne Amann, Raphaelle Guillou, et al.. First experimental evidence of oxygen ordering in dilute titanium-oxygen alloys. Materials Research Letters, 2022, 10, pp.481-487. ⟨10.1080/21663831.2022.2057202⟩. ⟨cea-03652065⟩