Question

Why does a new aluminium vessel lose shine so soon after use?

Answer 1

Aluminium is remarkable for its low density and its ability to resist corrosion through the phenomenon of passivation.

Passivation, in physical chemistry and engineering, refers to a material becoming "passive," that is, less affected or corroded by the environment of future use. Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build from spontaneous oxidation in the air. As a technique, passivation is the use of a light coat of a protective material, such as metal oxide, to create a shell against corrosion