title: Identifying suboxide grains at the metal-oxide interface of a corroded Zr-1.0%Nb alloy using (S)TEM, transmission-EBSD and EELS.
abstract: Here we report a methodology combining TEM, STEM, Transmission-EBSD and EELS to analyse the structural and chemical properties of the metal-oxide interface of corroded Zr alloys in unprecedented detail. TEM, STEM and diffraction results revealed the complexity of the distribution of suboxide grains at the metal-oxide interface. EELS provided accurate quantitative analysis of the oxygen concentration across the interface, identifying the existence of local regions of stoichiometric ZrO and Zr3O2 with varying thickness. Transmission-EBSD confirmed that the suboxide grains can be indexed with the hexagonal ZrO structure predicted with ab initio by Nicholls et al. (2014). The t-EBSD analysis has also allowed for the mapping of a relatively large region of the metal-oxide interface, revealing the location and size distribution of the suboxide grains.
authors.affiliation: Department of Materials, University of Oxford, Parks Road, Oxford, UK. Electronic address: jing.hu@materials.ox.ac.uk.
authors.forename: Jing
authors.initials: J
authors.lastname: Hu
authors.affiliation: Materials Performance Centre, School of Materials, University of Manchester, Manchester, UK.
authors.forename: Alistair
authors.initials: A
authors.lastname: Garner
authors.affiliation: Department of Materials, Imperial College London, Royal School of Mines, London, UK.
authors.forename: Na
authors.initials: N
authors.lastname: Ni
authors.affiliation: Materials Performance Centre, School of Materials, University of Manchester, Manchester, UK.
authors.forename: Ali
authors.initials: A
authors.lastname: Gholinia
authors.affiliation: Department of Materials, University of Oxford, Parks Road, Oxford, UK.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Nicholls
authors.affiliation: Department of Materials, University of Oxford, Parks Road, Oxford, UK.
authors.forename: Sergio
authors.initials: S
authors.lastname: Lozano-Perez
authors.affiliation: Materials Performance Centre, School of Materials, University of Manchester, Manchester, UK.
authors.forename: Philipp
authors.initials: P
authors.lastname: Frankel
authors.affiliation: Materials Performance Centre, School of Materials, University of Manchester, Manchester, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Preuss
authors.affiliation: Department of Materials, University of Oxford, Parks Road, Oxford, UK.
authors.forename: Chris R M
authors.initials: CR
authors.lastname: Grovenor
keywords: (S)TEM; EELS; Oxidation mechanism; Suboxide; Transmission Kikuchi Diffraction; Transmission-EBSD; Zirconium alloys