Applications
Dysprosium is used, in conjunction with vanadium and other elements, in making laser materials and commercial lighting. Because of dysprosium's high thermal neutron absorption cross-section, dysprosium oxide-nickel cermets are used in neutron-absorbing control rods in nuclear reactors. Dysprosium-cadmium chalcogenides are sources of infrared radiation which is useful for studying chemical reactions. Because dysprosium and its compounds are highly susceptible to magnetization, they are employed in various data storage applications, such as in hard disks.
Neodymium-iron-boron magnets can have up to 6% of the neodymium substituted with dysprosium to raise the coercivity for demanding applications such as drive motors for hybrid electric vehicles. This substitution would require up to 100 grams of dysprosium per hybrid car produced. Based on Toyota's projected 2 million units per year, the use of dysprosium in applications such as this would quickly exhaust the available supply of the metal. The dysprosium substitution may also be useful in other applications, as it improves the corrosion resistance of the magnets.
Dysprosium is one of the components of Terfenol-D, along with iron and terbium. Terfenol-D has the highest room-temperature magnetostriction of any known material; this property is employed in transducers, wide-band mechanical resonators, and high-precision liquid fuel injectors.
Dysprosium is used in dosimeters for measuring ionizing radiation. Crystals of calcium sulfate or calcium fluoride are doped with dysprosium. When these crystals are exposed to radiation, the dysprosium atoms become excited and luminescent. The luminescence can be measured to determine the degree of exposure to which the dosimeter has been subjected.
Nanofibers of dysprosium compounds have high strength and large surface area; therefore, they can be used for reinforcement of other materials and as a catalyst. Fibers of dysprosium oxide fluoride can be produced by heating an aqueous solution of DyBr and NaF to 450 °C at 450 bar pressure for 17 hours. This material is remarkably robust, surviving over 100 hours in various aqueous solutions at temperatures exceeding 400 °C without re-dissolving or aggregating.
Dysprosium iodide and dysprosium bromide are used in high intensity lighting. These compounds dissociate near the hot center of the lamp releasing isolated dysprosium atoms. The latter re-emit light in the green and red part of the spectrum thereby effectively producing bright light.
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