At One Place

Does nickel rust?

Does nickel rust?
It corrodes, but it does not rust
nickel

Highly corrosion resistant, which is why it is plated onto other metals and alloyed into stainless steel.

Rust is not the same as corrosion

Rust means iron oxide specifically. Only iron and things containing iron can rust, so "does aluminium rust" is a category error — aluminium corrodes vigorously and does not rust. That distinction is not pedantry, because the two oxides behave in opposite ways. Iron oxide is porous, flakes off and exposes fresh metal underneath, so rusting continues until the metal is gone. Aluminium, chromium, zinc and titanium form dense oxide films that seal the surface and stop the reaction, and re-form within milliseconds if scratched.

What rusting needs

  • Iron, oxygen and water — all three. Iron in dry air does not rust, and iron in oxygen-free water does not either, which is why iron shipwrecks in deep anoxic water survive and ones in shallow oxygenated water do not.
  • Salt accelerates it dramatically, by making the water conductive and allowing the electrochemistry to proceed faster. This is the entire reason coastal and road-salted cars rot.
  • Contact with a more noble metal accelerates it — galvanic corrosion. Steel bolted to copper or carbon fibre corrodes far faster than steel alone.
  • Rust occupies roughly six times the volume of the steel it came from, which is why it cracks concrete and jams bolts rather than simply thinning them.

How it compares

Material Rusts? What actually happens
mild steel Yes — it contains iron, so it rusts Rusts readily and completely. Unprotected mild steel outdoors loses measurable thickness every year.
aluminum It corrodes, but it does not rust Aluminium oxidises within milliseconds of exposure, and the oxide layer is dense, adherent and self-healing — the opposite of rust. This is why an untreated aluminium window frame outlasts a painted steel one.
water Neither rusts nor meaningfully corrodes Water does not rust; it is the agent that makes iron rust, together with oxygen. Neither alone is enough.
copper It corrodes, but it does not rust Copper forms a green patina of copper carbonate, which is protective and self-limiting. The Statue of Liberty is copper and its skin is about 2.4 mm thick after 140 years.
gold Neither rusts nor meaningfully corrodes Gold does not oxidise in air at any temperature. Gold recovered from shipwrecks after centuries is unchanged.
titanium It corrodes, but it does not rust Forms an extremely stable oxide film. Titanium is essentially immune to seawater, which is why it is used for submarine and marine hardware.
concrete It corrodes, but it does not rust Concrete itself does not rust; the steel inside it does, and that is the main way reinforced concrete fails. Rust occupies about six times the volume of the steel it came from, so it cracks the concrete outward from within — the stains and spalling on an old car park are that process.
stainless steel 304 It corrodes, but it does not rust Does not rust in normal use, because chromium oxide blocks it. It will stain and pit if the oxide layer is damaged and cannot re-form — under a rubber mat, or where iron particles from a grinder have embedded in the surface.
iron Yes — it contains iron, so it rusts Iron oxide is flaky and porous rather than protective, so rust does not stop the reaction — it exposes fresh metal and the corrosion continues inward until nothing is left.
air Neither rusts nor meaningfully corrodes Air does not corrode; it is half the reason other things do. Iron needs both oxygen and water to rust, and neither alone will do it.
ice Neither rusts nor meaningfully corrodes Does not corrode. It causes enormous mechanical damage by expanding about 9 % on freezing.
lead It corrodes, but it does not rust Forms a dull grey oxide-carbonate layer that protects it well. Lead roofing on cathedrals has lasted centuries.
tungsten It corrodes, but it does not rust Very resistant at room temperature; oxidises readily when hot, which is why filament bulbs had to be evacuated or gas-filled.
brass It corrodes, but it does not rust Tarnishes and can dezincify — in the wrong water chemistry the zinc leaches out and leaves a porous copper skeleton that looks intact and has almost no strength. Plumbing brasses are specified as dezincification-resistant for that reason.
pine Neither rusts nor meaningfully corrodes Does not corrode. It rots, which is a biological process rather than a chemical one and needs moisture and oxygen.
silver It corrodes, but it does not rust Silver tarnishes to silver sulfide, reacting with traces of sulfur in air rather than with oxygen — which is why it blackens faster near eggs, onions and rubber bands.
gray cast iron Yes — it contains iron, so it rusts Rusts fast when bare. Seasoning a pan is a polymerised oil layer that physically excludes water — it is a barrier, not a chemical passivation like stainless.
diamond Neither rusts nor meaningfully corrodes Chemically inert at room temperature. It burns in oxygen above about 800 °C.

Common questions

Does nickel rust?
It corrodes, but it does not rust. Highly corrosion resistant, which is why it is plated onto other metals and alloyed into stainless steel.
What is the difference between rust and corrosion?
Rust is iron oxide specifically, so only iron and iron alloys rust. Corrosion is the general term. The practical difference is that iron oxide is porous and lets the reaction continue, while aluminium, chromium, zinc and titanium form dense self-healing oxide films that stop it.
Why does salt make things rust faster?
It makes the water conductive, which lets the electrochemical reaction proceed much faster. It is why coastal and road-salted vehicles corrode in a fraction of the time.

Related pages

Sources

  1. Guide for the Use of the International System of Units (SP 811) — NIST (Public domain (US Government))

How these figures are compiled and checked