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For color TV tubes. | Atomic Number: | 66 | Atomic Symbol: | Dy | | Atomic Weight: | 162.50 | Electron Configuration: | 2-8-28-8-2 | | Shells: | 2,8,18,28,8,2 | Filling Orbital: | 4f10 | | Melting Point: | 1412oC | Boiling Point: | 2562oC | | Description: | Rare earth metal. |
History(Gr. dysprositos, hard to get at) Dysprosium was discovered in
1886 by Lecoq de Boisbaudran, but not isolated. Neither the oxide nor the metal
was available in relatively pure form until the development of ion-exchange
separation and metallographic reduction techniques by Spedding and associates
about 1950.
OccurenceDysprosium occurs along with other so-called rare-earch or
lanthanide elements in a variety of minerals such as xenotime, fergusonite,
gadolinite, euxenite, polycrase, and blomstrandine. The most important sources,
however, are from monaziate and bastnasite.
Properties- Dysprosium can be prepared by reduction of the trifluoride with calcium.
- The elemtn has a metallic, bright silver luster. It is relatively stable in
air at room temperature, and is readily attacked and dissolved, with the
evolution of hydrogen, but dilute and concentrated mineral acides.
- The metal is soft enough to be cut with a knife and can be machined without
sparking if overheating is avoided.
- Small amounts of impurities can greatly affect its physical properties.
Uses- While dysprosium has not yet found many applications, its thermal neutron
absorption cross-section and high melting point suggest metallurgical uses in
nuclear control applications and for alloying with special stainless steels.
- A dysprosium oxide-nickel cermet has found use in cooling nuclear reactor
rods.
- This cermet absorbs neutrons readily without swelling or contracting under
prolonged neutron bombardment.
- In combination with vanadium and other rare earths, dysprosium has been used
in making laser materials.
- Dysprosium-cadmium chalcogenides, as sources of infrared radiation, have
been used for studying chemical reactions.
CostsThe cost of dysprosium metal has dropped in recent years since the
development of ion-exchange and solvent extraction techniques, and the discovery
of large ore bodies. The metal costs about $300/kg in purities of 99+%.
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