Uses of Dysprosium
Dysprosium is good at absorbing neutrons and so it is used in dysprosium-oxide-nickel cement in control rods in nuclear reactors.
Terfenol-D (a terbium, iron and dysprosium alloy) expands or contracts in the presence of a magnetic field (magnetostriction) and is used in ships’ sonar systems and in sensors and transducers. Terfenol-D is also used in a speaker called the ‘SoundBug’, which turns any flat surface into a speaker.