Focused Ion Beam induced hydride formation does not affect Fe, Ni, Cr-clusters in irradiated Zircaloy-2
Journal article, 2023

Room temperature focused ion beam (FIB) milling is known to potentially promote the formation of hydrides in zirconium and its alloys. We used atom probe tomography (APT) to determine the composition of irradiated and as-produced Zircaloy-2 fuel cladding. We consistently found ∼ 50 at% hydrogen in all room temperature FIB-milled specimens run in voltage pulsing APT measurements. Crystallographic analysis of APT data however showed slightly better agreement with δ-hydride (ZrH2, FCC, ∼ 60–66.7 at% H) than γ-hydride (ZrH, FCT, ∼ 50 at% H). Electron energy loos spectroscopy (EELS) measurements prior to APT analyses confirmed the presence of δ-hydride. Hence, APT gives a systematic underestimation of hydrogen for Zr-hydride. Milling at cryogenic temperatures was found to not cause such hydride formation. However, we did not find significant differences in the clusters formed by segregation of the alloying elements Fe, Cr and Ni to irradiation induced a-loops whether the material was identified as α-Zr or hydride. Therefore, analyzing irradiation-induced redistribution of alloying elements in Zr fuel cladding using APT does not rely on FIB preparation at cryogenic temperatures. However, in conjunction with voltage pulsing APT cryo-FIB can be worthwhile if one aims at investigating hydrogen distribution or hydrides.

Irradiation effects

Atom probe tomography

Clustering

Zirconium hydrides

Zirconium fuel cladding

Focused ion beam

Author

David Mayweg

Chalmers, Physics, Microstructure Physics

Johan Eriksson

Chalmers, Physics, Microstructure Physics

Olof Bäcke

Chalmers, Physics, Microstructure Physics

Andrew J. Breen

The University of Sydney

Mattias Thuvander

Chalmers, Physics, Microstructure Physics

Journal of Nuclear Materials

0022-3115 (ISSN)

Vol. 581 154444

Subject Categories

Inorganic Chemistry

Atom and Molecular Physics and Optics

Corrosion Engineering

Condensed Matter Physics

Areas of Advance

Energy

Materials Science

Infrastructure

Chalmers Materials Analysis Laboratory

DOI

10.1016/j.jnucmat.2023.154444

More information

Latest update

8/3/2023 9