Glossary of surface technology
Aluminium oxide
2O3, hard oxide occurring in various modifications; of these, corundum has the greatest hardness. In contact with atmospheric oxygen, a thin transparent Al2O3 coat is formed spontaneously on aluminium surfaces which protects the aluminium from further oxidation (self-passivation). Anodising artificially reinforces this oxide coat and thus its protective effect. Al2O3 surfaces can be etched in the plasma by means of Ar bombardment or halogenated gases.
