Element · Dy

Dysprosium

The element that keeps electric vehicle motors working when they get hot, and a persistent supply worry.

Dysprosium is a rare earth whose importance is entirely about temperature. Neodymium-iron-boron magnets weaken as they warm, and a motor magnet in a car gets hot; adding dysprosium raises the temperature at which the magnet demagnetises.

The name comes from the Greek for hard to get at, given when it proved difficult to isolate. The name has aged well. Dysprosium is one of the rare earths most concentrated in a small number of deposits, and demand from electric vehicles and wind turbines has made its supply a strategic concern for several governments.

Uses

Almost all dysprosium goes into permanent magnets for traction motors in electric and hybrid vehicles, and for direct-drive wind turbine generators — the applications where a magnet must survive both heat and decades of service.

Because supply is constrained, considerable engineering effort goes into using less of it: grain boundary diffusion places dysprosium only where it is needed at the magnet's surface rather than throughout. Dysprosium is also used in control rods, in dosimeters, and in magnetostrictive alloys that change shape in a magnetic field.

Medium confidence Weak evidence

How we know: checked recently · only one source, so there is nothing to cross-check it against · stated directly by the source.

How this connects

Where a connection has been confirmed by an outside reference, that reference is named beside it.

is used as

Permanent magnets — application · raises the temperature at which the magnet demagnetises

is produced by

Rare earth separation — process · a heavy rare earth; the separation is the same cascade, run longer because the differences are smaller

is an alternative to

Terbium — element · as the heavy rare earth added to a neodymium magnet to stop it demagnetising when hot. Terbium does the job at lower addition rates and costs more, and reducing the need for either is an active research goal precisely because both are supply-concentrated

is a component of

Neodymium magnet — alloy · 0–8% · a few per cent in the grades that have to work hot, which is what a traction motor needs — and the single most supply-constrained ingredient in the magnet

is used in

Smartphone — object · a few per cent of the magnet, and there for one reason: coercivity falls with temperature and the magnet sits next to a warm processor

Sources

Material World
Our own writing
Wikidata
Wikimedia Foundation · Creative Commons CC0 1.0 Universal (public domain dedication)
PubChem
US National Library of Medicine · Mixed — aggregated third-party content, rights retained by depositors
NIST — National Institute of Standards and Technology
United States Department of Commerce · US Government work — public information, credit requested

Questions this page answers

Where it comes from, and what it becomes

Follow Dysprosium back to what it starts as, and forward into what it becomes. Each step is a documented one — a real route material takes, not a chain of inference.

Upstream — what it comes from

Dysprosium → is produced by (a heavy rare earth; the separation is the same cascade, run longer because the differences are smaller) → Rare earth separation → takes as input (the principal ore of the light rare earths, carrying all of them together) → Bastnäsite
Dysprosium → is produced by (a heavy rare earth; the separation is the same cascade, run longer because the differences are smaller) → Rare earth separation → takes as input (the other feed alongside bastnäsite, bringing thorium into the residues with it) → Monazite
Dysprosium → is produced by (a heavy rare earth; the separation is the same cascade, run longer because the differences are smaller) → Rare earth separation → takes as input (the heavy rare earth feed, where monazite and bastnäsite bring the light ones) → Xenotime

Downstream — what it becomes

Dysprosium → is used in (a few per cent of the magnet, and there for one reason: coercivity falls with temperature and the magnet sits next to a warm processor) → Smartphone → is used in (and it is where four separate raw-material arguments meet — the 3TG conflict minerals, cobalt, the rare earths, and everything too dispersed to recover) → Electronics manufacture → is associated with (and the supply chain it produced is the deepest and most concentrated in the world economy) → The semiconductor era complete chain
Dysprosium → is a component of (a few per cent in the grades that have to work hot, which is what a traction motor needs — and the single most supply-constrained ingredient in the magnet) → Neodymium magnet → is used as (the strongest in commercial use, and the reason a motor, a hard drive and an earbud can be small) → Permanent magnets
Dysprosium → is used as (raises the temperature at which the magnet demagnetises) → Permanent magnets
Dysprosium → is used in (a few per cent of the magnet, and there for one reason: coercivity falls with temperature and the magnet sits next to a warm processor) → Smartphone → is associated with (the object the whole period arrives at, and the one that put roughly sixty elements into a pocket) → The semiconductor era complete chain
Dysprosium → is a component of (a few per cent in the grades that have to work hot, which is what a traction motor needs — and the single most supply-constrained ingredient in the magnet) → Neodymium magnet → is used in (direct-drive wind turbine generators, which is what put rare-earth supply into energy policy) → Energy generation
Dysprosium → is used in (a few per cent of the magnet, and there for one reason: coercivity falls with temperature and the magnet sits next to a warm processor) → Smartphone → is used as (and the radio front end alone reaches gallium arsenide, gallium nitride and a dozen filters made of piezoelectric ceramic) → Telecommunications