Journal of Materials Science

, Volume 52, Issue 10, pp 5537–5543 | Cite as

Local investigation of the emissive properties of LaB6–ZrB2 eutectics

  • M.-H. Berger
  • T. C. Back
  • P. Soukiassian
  • D. Martinotti
  • L. Douillard
  • S. B. Fairchild
  • J. J. Boeckl
  • V. Filipov
  • A. Sayir
Eutectics

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.

Notes

Acknowledgements

M. H. Berger and T. C. Back would like to acknowledge support from the Air Force Office of Scientific Research (AFOSR). TC Back would also like to acknowledge Prof. Martin Kordesch for useful discussions.

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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.MINES ParisTech, PSL Research University, MAT - Centre des matériaux, CNRS UMR 7633EvryFrance
  2. 2.University of Dayton Research InstituteDaytonUSA
  3. 3.Air Force Research LaboratoryMaterials and Manufacturing DirectorateWright-Patterson Air Force BaseUSA
  4. 4.SPEC, CEA, CNRSUniversité Paris-Saclay CEA SaclayGif Sur YvetteFrance
  5. 5.Université Paris-SudOrsayFrance
  6. 6.Frantsevitch Institute for Problems of Materials SciencesNational Academy of Sciences of UkraineKievUkraine
  7. 7.NASAGlenn Research CenterClevelandUSA
  8. 8.AFOSRArlingtonUSA

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