The University of Southampton
University of Southampton Institutional Repository

In situ TEM observations on the structural evolution of a nanocrystalline W-Ti alloy at elevated temperatures

In situ TEM observations on the structural evolution of a nanocrystalline W-Ti alloy at elevated temperatures
In situ TEM observations on the structural evolution of a nanocrystalline W-Ti alloy at elevated temperatures

The thermal stability and nanoscale structural evolution at elevated temperatures of a sputter deposited W-Ti alloy thin film were studied by a combination of ex situ and in situ techniques. XRD, FIB, SEM-EDX and STEM-EDX were used to characterise the film annealed ex situ in vacuum at 1373 K for 48 h. In situ TEM heating experiments were conducted at various temperatures up to 923 K to capture transitional phenomena occurring in the alloy upon heating and cooling. At a microscopic level, the alloy annealed at 1373 K for 48 h transformed from a single-phase β-(WTi) solid solution into a two-phase alloy consisting of Ti-rich grains in equilibrium with Ti-depleted β-(WTi) solid solution grains. In situ TEM observations revealed initial Ti segregations along columnar grain boundaries at T ∼ 423–573 K, followed by Ti-rich clusters formation in the grains interior at T ∼ 573–773 K. The microstructure observed at 923 K remained stable upon cooling to room temperature and consisted of Ti-rich segregations along the columnar grain boundaries and of alternate Ti-rich and Ti-depleted nanoscale domains in the grains interior, which formed a stable dual-phase nanocrystalline structure.

High-temperature alloys, In situ TEM heating, Phases separation, Physical vapour deposition (PVD)
0925-8388
1000-1008
Callisti, M.
86e03724-aacc-46d5-bccc-4c7025556667
Tichelaar, F.D.
b96cf2d4-b18c-48a5-87e2-236b9f48aa60
Polcar, T.
c669b663-3ba9-4e7b-9f97-8ef5655ac6d2
Callisti, M.
86e03724-aacc-46d5-bccc-4c7025556667
Tichelaar, F.D.
b96cf2d4-b18c-48a5-87e2-236b9f48aa60
Polcar, T.
c669b663-3ba9-4e7b-9f97-8ef5655ac6d2

Callisti, M., Tichelaar, F.D. and Polcar, T. (2018) In situ TEM observations on the structural evolution of a nanocrystalline W-Ti alloy at elevated temperatures. Journal of Alloys and Compounds, 749, 1000-1008. (doi:10.1016/j.jallcom.2018.03.335).

Record type: Article

Abstract

The thermal stability and nanoscale structural evolution at elevated temperatures of a sputter deposited W-Ti alloy thin film were studied by a combination of ex situ and in situ techniques. XRD, FIB, SEM-EDX and STEM-EDX were used to characterise the film annealed ex situ in vacuum at 1373 K for 48 h. In situ TEM heating experiments were conducted at various temperatures up to 923 K to capture transitional phenomena occurring in the alloy upon heating and cooling. At a microscopic level, the alloy annealed at 1373 K for 48 h transformed from a single-phase β-(WTi) solid solution into a two-phase alloy consisting of Ti-rich grains in equilibrium with Ti-depleted β-(WTi) solid solution grains. In situ TEM observations revealed initial Ti segregations along columnar grain boundaries at T ∼ 423–573 K, followed by Ti-rich clusters formation in the grains interior at T ∼ 573–773 K. The microstructure observed at 923 K remained stable upon cooling to room temperature and consisted of Ti-rich segregations along the columnar grain boundaries and of alternate Ti-rich and Ti-depleted nanoscale domains in the grains interior, which formed a stable dual-phase nanocrystalline structure.

Text
Manuscript_accepted - Accepted Manuscript
Restricted to Repository staff only until 28 March 2019.
Request a copy

More information

Accepted/In Press date: 26 March 2018
e-pub ahead of print date: 28 March 2018
Published date: 15 June 2018
Keywords: High-temperature alloys, In situ TEM heating, Phases separation, Physical vapour deposition (PVD)

Identifiers

Local EPrints ID: 419955
URI: https://eprints.soton.ac.uk/id/eprint/419955
ISSN: 0925-8388
PURE UUID: ed2fa51c-330b-4204-9f18-11a84991cdbd
ORCID for T. Polcar: ORCID iD orcid.org/0000-0002-0863-6287

Catalogue record

Date deposited: 24 Apr 2018 16:30
Last modified: 14 Mar 2019 01:36

Export record

Altmetrics

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×