The invisible hero inside your computer. Hafnium hides in every modern processor — in billions of transistors. Without hafnium oxide, Intel and AMD couldn't shrink chips below 45 nanometers. This metal quietly powers the technology revolution.
But hafnium has another superpower. It absorbs neutrons more greedily than most elements. That's why it's used for control rods in nuclear reactors. One push of a rod — and the chain reaction slows down. Hafnium literally keeps atomic energy under control.
Hafnium is a lustrous silvery-gray metal with a density of 13.31 g/cm³. It melts at 2,506 K and boils at 4,876 K. Chemically, it's nearly identical to zirconium — which is why it took so long to discover.
In 1923, Danish scientists Coster and Hevesy finally found it using X-ray analysis. They named it after Copenhagen (Latin: Hafnia). Hafnium resists corrosion, withstands extreme temperatures, and doesn't react with most acids. An ideal material for conditions where other metals give up.
Bulk hafnium is safe to handle. But fine hafnium powder is pyrophoric — it can spontaneously ignite in air. Shavings and dust burn with a bright flame that's hard to extinguish with water. Some hafnium compounds irritate skin and respiratory tract. Machining requires ventilation and dust protection.
Every Intel and AMD processor since 2007 contains hafnium oxide. A 2-nanometer layer replaced silicon dielectric and saved Moore's Law.
The name Hafnium comes from Hafnia, the Latin name for Copenhagen. It's one of the few elements named after a capital city.
Hafnium absorbs neutrons 600 times better than zirconium. That's why they must be separated for the nuclear industry.
Scientists searched for hafnium for nearly 50 years. It was hiding in zirconium minerals, because these two elements are chemically almost identical.
Hafnium melts at 2,506 K — higher than platinum. Its alloys withstand the temperatures inside jet engines.
| Isotope | Mass (u) | Abundance | Half-life | Decay |
|---|---|---|---|---|
174Hf☢ | 173.940046 | 0.16% | 2×10¹⁵ years | α |
176Hf | 175.941409 | 5.26% | stable | — |
177Hf | 176.943221 | 18.60% | stable | — |
178Hf | 177.943699 | 27.28% | stable | — |
179Hf | 178.945816 | 13.62% | stable | — |
180Hf | 179.946550 | 35.08% | stable | — |
X-ray spectroscopic analysis of zirconium ore