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Material World
Element · Ta

Tantalum

The capacitor metal, and the one whose supply chain forced an industry to think about where its materials come from.

Tantalum forms an oxide layer that is thin, stable and an excellent dielectric, which makes tantalum capacitors unusually compact for their capacitance. That property is why they are in phones and hearing aids rather than something bulkier.

It is also, along with tin, tungsten and gold, one of the four minerals whose trade financed armed conflict in the Great Lakes region — the reason "3TG" reporting requirements exist. Tantalum is a rare case where a material's supply chain became a regulatory subject in its own right.

Name origin

After Tantalus, punished with water he could not drink — a reference to the metal's refusal to absorb acid.

Uses

Tantalum's dominant use is the capacitor. Its oxide layer is an unusually effective dielectric, so a tantalum capacitor stores more charge in less volume than the alternatives — which is why they are found in phones, hearing aids and implanted medical devices where space is the binding constraint.

It is also almost completely inert and not rejected by living tissue, so it is used for surgical implants and plates. Tantalum carbide is added to cutting tools, and tantalum chemical plant equipment handles acids that would destroy stainless steel.

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 an alternative to

  • Niobium — element · chemically near-identical and historically confused

is used as

is extracted from

  • Columbite — mineral · the principal source; the two are separated by solvent extraction after mining, not before

is produced by

  • Solvent extraction and electrowinning — process · separated from niobium by solvent extraction, which is the hard step; the metal itself is reduced from the resulting salt afterwards

is a component of

  • Nickel superalloy — alloy · 0–9% · in the single-crystal alloys, where it strengthens the strengthening phase itself

is used in

  • Smartphone — object · in the capacitors, whose oxide film holds hundreds of times its own thickness in voltage — more capacitance per cubic millimetre than anything else, which is why the metal survived miniaturisation

is found in

  • Columbite — mineral · substitutes within a solid solution — an individual specimen may hold little of it

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 Tantalum 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

  • Tantalum → is produced by (separated from niobium by solvent extraction, which is the hard step; the metal itself is reduced from the resulting salt afterwards) → Solvent extraction and electrowinning → takes as input (in the low-grade and oxidised ores that flotation cannot economically treat, with bacteria oxidising the sulfide into a form the acid can attack) → Chalcopyrite
  • Tantalum → is extracted from (the principal source; the two are separated by solvent extraction after mining, not before) → Columbite
  • Tantalum → is produced by (separated from niobium by solvent extraction, which is the hard step; the metal itself is reduced from the resulting salt afterwards) → Solvent extraction and electrowinning → takes as input (a carbonate dissolves straight into acid, which is why an oxidised orebody goes to a leach pad and the sulfide beneath it goes to a smelter) → Malachite
  • Tantalum → is produced by (separated from niobium by solvent extraction, which is the hard step; the metal itself is reduced from the resulting salt afterwards) → Solvent extraction and electrowinning → takes as input (leached with acid or alkali depending on the host rock, which is what decides the flowsheet of a uranium mill) → Uraninite

Downstream — what it becomes

  • Tantalum → is a component of (in the single-crystal alloys, where it strengthens the strengthening phase itself) → Nickel superalloy → is used in (cast as a single crystal, because at temperature and sustained load the failure mode is creep along grain boundaries — so the boundaries are removed entirely) → Turbine blade → is associated with (the jet engine created the superalloy industry, because no existing material survived the turbine inlet — and turbine temperature has risen about 500 °C since, almost entirely on the blade) → The wartime materials programmes complete chain
  • Tantalum → is used in (in the capacitors, whose oxide film holds hundreds of times its own thickness in voltage — more capacitance per cubic millimetre than anything else, which is why the metal survived miniaturisation) → 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
  • Tantalum → is used as (as a capacitor dielectric substrate, not as a conductor) → Electrical conduction
  • Tantalum → is a component of (in the single-crystal alloys, where it strengthens the strengthening phase itself) → Nickel superalloy → is associated with (the jet engine created the industry, because no existing material survived the turbine inlet) → The wartime materials programmes complete chain
  • Tantalum → is used in (in the capacitors, whose oxide film holds hundreds of times its own thickness in voltage — more capacitance per cubic millimetre than anything else, which is why the metal survived miniaturisation) → 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
  • Tantalum → is a component of (in the single-crystal alloys, where it strengthens the strengthening phase itself) → Nickel superalloy → is used as (the turbine blade carries its own centrifugal load at four fifths of its melting point, which is structural engineering under the hardest conditions anybody attempts) → Structural engineering

These are the most distinct paths onward. Tantalum ends up in others besides.