Dysprosium, isolated in 1886, derives its name from the Greek dysprositos meaning "hard to get"... and judging by its scarcity and price, it still is.
Dysprosium has a metallic, bright silver lustre. It is relatively stable in air at room temperature, but dissolves readily, with the evolution of hydrogen, in mineral acids. The metal is soft enough to be cut with a knife and can be machined without sparking if overheating is avoided. It is generally found in small amounts in minerals such as xenotime (Y,REE PO4), monazite ((Ce,La,Th,Nd,Y,) PO4) and bastnaesite ((Ce,La,Y)CO3F).
Dysprosium's physical characteristics can be greatly affected even by small amounts of impurities. It is relatively stable in air at room temperature, but it dissolves readily in dilute or concentrated mineral acids with the release of hydrogen. Dysprosium also reacts with water and the halogens at higher temperatures and it has one of the highest magnetic strengths of the elements, especially at low temperatures.
APPLICATIONS OF DYSPROSIUM
Magnets - Electromotive: Neodymium-iron-boron magnets or Neo-Magnets can have up to 6% of the neodymium substituted with dysprosium to raise the coercivity or strength, for demanding applications such as drive motors for hybrid electric vehicles. The dysprosium substitution also tends to improve the corrosion resistance of the magnets. This substitution would require up to 100 grams of dysprosium per hybrid car produced.
Magnets - Electronics: Dysprosium is used in various data storage applications such as in compact discs. It is also one of the components of ‘Terfenol-D', along with iron and terbium, which has the highest room-temperature magnetoresistance of any known material, a property employed in transducers, wide-band mechanical resonators and high-precision liquid fuel injectors.
Energy: Because of dysprosium's high, thermal neutron absorption cross-section, dysprosium oxide-nickel cements are used in neutron-absorbing control rods in nuclear reactors; Dysprosium also used in dosimeters for measuring ionizing radiation.
Chemicals: Dysprosium-cadmium chalcogenides are sources of infrared radiation used in the study of chemical reactions.
Ceramics and Specialty Glass: Dysprosium is used in conjunction with vanadium and other elements in making laser materials.
Note: Like many powders, dysprosium powder may present an explosion hazard when mixed with air and when an ignition source is present. Thin foils of the substance can also be ignited by sparks or by static electricity. Dysprosium fires cannot be put out by water.
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