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Erschienen in: Journal of Materials Science 10/2017

30.01.2017 | Eutectics

Local investigation of the emissive properties of LaB6–ZrB2 eutectics

verfasst von: M.-H. Berger, T. C. Back, P. Soukiassian, D. Martinotti, L. Douillard, S. B. Fairchild, J. J. Boeckl, V. Filipov, A. Sayir

Erschienen in: Journal of Materials Science | Ausgabe 10/2017

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Abstract

LaB6–ZrB2 composites obtained by directional solidification at eutectic composition have been investigated by low-energy electron microscopy (LEEM) and thermal emission electron microscopy (ThEEM). The transitions from the mirror electron microscopy mode to the LEEM mode for the hexa- and diborides indicate lower work functions of the two phases when embedded in the composite compared to the corresponding single phases. In the composite, the work function of the ZrB2 fibers is similar to that of the matrix and ThEEM images display a brighter contrast for the fibers. This is explained by the thermally activated diffusion of La on the fiber surface.

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Metadaten
Titel
Local investigation of the emissive properties of LaB6–ZrB2 eutectics
verfasst von
M.-H. Berger
T. C. Back
P. Soukiassian
D. Martinotti
L. Douillard
S. B. Fairchild
J. J. Boeckl
V. Filipov
A. Sayir
Publikationsdatum
30.01.2017
Verlag
Springer US
Erschienen in
Journal of Materials Science / Ausgabe 10/2017
Print ISSN: 0022-2461
Elektronische ISSN: 1573-4803
DOI
https://doi.org/10.1007/s10853-017-0816-0

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