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Journal of Materials Science

, Volume 53, Issue 16, pp 11749–11764 | Cite as

Metastable monotectic phase separation in Co–Cu alloys

  • Oluwatoyin E. JegedeEmail author
  • Robert F. Cochrane
  • Andrew M. Mullis
Metals

Abstract

The liquid phase separation behaviour of metastable monotectic Co–Cu alloys was investigated as a function of cooling rate using a 6.5 m drop-tube facility. A range of liquid phase separated morphologies were observed including stable two-layer core–shell, evolving core–shell and dendritic structures. It was found that in the core–shell structures the core was always in the higher melting point (Co-rich) phase, irrespective of the core and shell volume fraction. In Cu–50 at% Co alloy, high cooling rates were observed to yield two episodes of liquid phase separation, corresponding to binodal, followed by spinodal decomposition. The resulting structure comprised a core–shell structure in which the Co-rich core contained a very fine dispersion of Cu-rich particles with a Cu-rich shell which may, or may not, contain a similar dispersion of Co-rich particles.

Notes

Acknowledgements

Oluwatoyin Jegede is a commonwealth scholar, sponsored by the UK government.

Compliance with ethical standards

Conflict of interest

The authors declare they have no conflict of interest related to this work.

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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Chemical and Process EngineeringUniversity of LeedsLeedsUK

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