Rare earth metals are a collection of 17 chemical elements that rarely exist in pure form. Three important rare earth metals are scandium, gadolinium, and ytterbium. Scandium is mainly used for research and in mercury vapor lamps. Gadolinium is used in alloys for high temperature resistance and oxidation resistance, and in gadolinium yttrium garnets for microwave applications. Ytterbium is used in stress gauges to monitor ground deformations and in alloys to improve strength. Neodymium plays an essential role in miniaturizing devices by creating powerful permanent magnets used in motors, phones, and turbines.
3. Definition of Rare Earth metals
¡ñ Name alludes to their elusive nature as they rarely exist
in their pure form
¡ñ Collection of 17 chemical elements in the periodic table
(15 lanthanides, Scandium and Yttrium)
¡ñ Scandium and Yttrium are considered rare earth
elements as they tend to occur in the same ore deposits
as the lanthanides and exhibit similar chemical
properties
4. Rare Earth Metal #1 - scandium
- A silvery metal that tarnishes in air, burns easily and reacts
with water
- Mainly used for research purposes
- Scandium Iodide is added to mercury vapour lamps to
produce a highly efficient light source resembling sunlight,
which is important for indoor lighting and night-time colour
television screens
- Also used as a tracing agent in refinery crackers for crude
- Has a great potential as its¡¯ density is almost as low as
aluminium, but has a much higher melting point, thus
attracting the interest of spacecraft designers.
5. Rare Earth Metal #2 - Gadolinium
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Gadolinium is a bright, soft, silvery-white metal that is both ductile and
malleable.
USES:
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Gadolinium is used in alloys of iron and chromium to improve resistance
to high temperatures and oxidation.
Gadolinium is used to make gadolinium yttrium garnets which have
microwave applications.
Gadolinium compounds are used as green phosphors in color television
picture tubes.
6. Rare Earth Metal #3 - Ytterbium
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Bright, soft, silvery-white metal that is both ductile and malleable
Tarnishes quickly in air
Reacts slowly with water
Dissolves rapidly in mineral acids
Extracted from mineral monazite by different extraction methods such as ion
exchange and solvent extraction
Uses of Ytterbium
¡ñ Radioactive isotope of ytterbium is used in portable x-ray machines that need no
electricity
¡ñ Used in stress gauges to monitor ground deformations caused by earthquakes or
underground explosions ¡ú Ytterbium¡¯s electrical resistance increases by order of
magnitude under very high physical stress
¡ñ Used in alloys and added to stainless steel to improve grain refinement and strength
7. Rare earth metal #4 -Neodymium
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1.
Neodymium is a silvery-white metal.
It is one of the more reactive earth metals and tarnishes in air,
forming an oxide layer that falls off and exposes more metal to
oxidation. -stored in light mineral oil or sealed in plastic
Used with iron and boron to create powerful permanent magnets (NIB
magnets). -used in motors, computer disk drives, handphones, cell
phones and wind turbines.
-->plays an essential role in the miniaturisation of gadgets (before, producing strong
magnetic fields for motors required big and heavy magnets)
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Used as a colourant for glasses and enamels
Used as a crystal in ND:YAG lasers- to treat skin cancers, for laser
hair removals and to cut and weld steels.