A Sweet Coating


Aluminium, used to build cars and jets, is remarkable for its ability to resist corrosion. When exposed to air, its surface layer forms a protective film that prevents degradation of the underlying metal.

But this film tends to break down in seawater. Usually toxic coatings are used to protect the metal. But the same effect can also be achieved by using the sweet juice of date fruit.

It is likely that the juice is adsorbed into the aluminium’s surface and the sugars react with the metal to form an anticorrosive film on the surface.


Down To Earth, October 2012