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Since gold is often considered "soft": If the Oscars were made of pure gold (instead of gold-plated britannium), would they bend (deform) over time?

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marked as duplicate by John Rennie, Emilio Pisanty, Qmechanic Feb 26 '13 at 1:48

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up vote 3 down vote accepted

Solid metals are crystals, not liquids.

The way any crystal plastically deforms is by motion of crystal dislocations.

Every crystal obeys a stress-strain curve, where stresses up to a certain amount do not result in permanent deformation. Higher stresses do result in permanent (plastic) deformation because dislocations move.

If a metal is "soft", all that means is the stress needed to start dislocations moving and plastically deform it is less than it is for other material.

If the applied stress is lower than that number, it will not permanently deform. It is not like a highly viscous liquid.

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