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For high strength magnets for disk drives. | Atomic Number: | 60 | Atomic Symbol: | Nd | | Atomic Weight: | 144.24 | Electron Configuration: | 2-8-22-8-2 | | Shells: | 2,8,18,22,8,2 | Filling Orbital: | 4f4 | | Melting Point: | 1010oC | Boiling Point: | 3127oC | | Description: | Silvery rare earth metal. | | Uses: | Used in ceramics to color glazes. |
History(Gr. neos, new, and didymos, twin)
- In 1841, Mosander, extracted from cerite a new rose-colored oxide, which he
believed contained a new element.
- He named the element didymium, as it was an inseparable twin brother of
lanthanum.
- In 1885 von Welsbach separated didymium into two new elemental components,
neodymia and praseodymia, by repeated fractionation of amonium didymium nitrate.
- While the free metal is in misch metal, long known and used as a pyrophoric
alloy for light flints, the element was not isolated in relatively pure form
until 1925.
- Neodymium is present in misch metal to the extent of about 18%.
- It is present in the minerals monazite and bastnasite, which are principal
sources of rare-earth metals.
- The element may be obtained by separating neodymium salts from other rare
eaths by ion-exchange or solvent extraction techniques, and by reducing
anhydrous halides such as NdF3 with calcium metal. Other separation techniques
are possible.
Properties- The metal has a bright silvery metallic luster, Neodymium is one of the more
reactive rare-earth metals and quickly tarnishes in air, forming an oxide that
spalls off and exposes metal to oxidation.
- The metal, therefore, should be kept under light mineral oil or sealed in a
plastic material.
- Neodymium exists in two allotropic forms, with a transformation from a
double hexagonal to a body-centered cubic structure taking place at 863C.
IsotopesNatural neodymium is a mixture of seven stable isotopes.
Fourteen other radioactive isotopes are recgnized.
UsesDidymium, of which neodymium is a component, is used for coloring glass to
make welder's goggles.
By itself, neodymium colors glass delicate shades ranging from pure violet
through wine-red and warm gray.
Light transmitted through such glass shows unusually sharp absorption bands.
The glass has been used in astronomical work to produce sharp bands by which
spectral lines may be calibrated.
Glass containing neodymium can be used as a laser material to produce
coherent light.
Neodymium salts are also used as a colorant for enamels.
CostsThe price of the metal is about $1/g.
HandlingNeodymium has a low-to-moderate actue toxic rating. As with
other rare earths, neodymium should be handled with care.
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