Aluminium oxynitride (marketed under the name
ALON by
Surmet Corporation[3]) is a
transparent ceramic composed of
aluminium,
oxygen and
nitrogen. Aluminium oxynitride is optically transparent (≥80% for 2 mm thickness) in the
near-ultraviolet, visible, and mid-wave-
infrared regions of the electromagnetic spectrum. It is four times as hard as
fused silica glass, 85% as hard as
sapphire, and nearly 115% as hard as
magnesium aluminate spinel. It can be fabricated into transparent windows, plates, domes, rods, tubes, and other forms using conventional ceramic powder processing techniques.[
citation needed]
Aluminium oxynitride is the hardest polycrystalline transparent ceramic available commercially.
[2][
needs update] Because of its relatively low weight, distinctive optical and mechanical properties, and resistance to oxidation or radiation, it shows promise for applications such as
bulletproof, blast-resistant, and optoelectronic windows.
[1] Aluminium oxynitride-based armor has been shown to stop multiple armor-piercing projectiles of up to .50 BMG.
[4]
