Atomic Properties of Dy
- Atomic Number of Dy
- 66
- Atomic Mass of Dy
- 162.5000 u
- Electron Configuration
- [Xe] 4f10 6s2
- Electronegativity
- 1.22
- Block
- f-block
- Group
- —
- Period
- 6
Paul-Émile Lecoq de Boisbaudran identified dysprosium in 1886 after a demanding series of separations from holmium-rich material. Its name comes from Greek dysprositos, meaning “hard to get at”. The phrase described the analytical challenge long before it described modern supply concerns.
Dysprosium now enters some neodymium-iron-boron magnets to improve resistance to demagnetization at elevated temperatures. It helps keep them from losing their power in demanding motors, generators, and actuators. The tradeoff is important: dysprosium can improve thermal performance but may reduce some room-temperature magnetic strength, while high cost and concentrated supply encourage engineers to minimize the amount used. Not every electric motor or wind turbine uses the same composition.
Its large magnetic moment and strong low-temperature magnetic response also make dysprosium useful in research and specialized materials. With terbium and iron it forms part of Terfenol-D, a magnetostrictive alloy that changes shape under a magnetic field. These applications arise from alloys and crystal structures, not from elemental dysprosium performing alone.
Seven stable isotopes occur naturally. The soft silvery metal tarnishes in air and is generally encountered industrially through compounds, separated oxides, and alloy additions.
This Luminary holds the line through careful optimization. “Hard to get” names the original purification struggle and still echoes in resource planning. Designers use dysprosium where added heat tolerance justifies the material, then work to achieve the required performance with as little of a scarce specialist as practical.