Aluminium oxynitride

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"AlON" redirects here. For the aircraft corporation, see Alon.

**Properties**
General
Name	Aluminium oxynitride
Chemical formula	(AlN)_x.(Al₂O₃)_1-x, mole fraction 0.30 ≤ x ≤ 0.37
Appearance	White or transparent solid
Physical
Melting point	~2140 °C
Boiling point	? ( Al₂O₃~3000°C)
Density	3.688 g/cm³
Crystal structure	cubic spinel
Solubility	insoluble
Thermochemistry
Δ_fH⁰_gas	? kJ/mol
Δ_fH⁰_solid	? kJ/mol
S⁰_{gas, 1 bar}	? J/mol·K
S⁰_solid	? J/mol·K
Safety
Ingestion	Classified ?
Inhalation	?
Skin	?
Eyes	?
More info	?
SI units were used where possible. Unless otherwise stated, standard conditions were used. Disclaimer and references

Aluminium oxynitride (AlON) is a transparent ceramic composed of aluminium, oxygen and nitrogen. It is marketed under the name ALON™ and described in U.S. Patent 4520116 . The material remains solid up to 1200°C, and is harder than glass. When formed and polished as a window, the material currently (2005) costs about USD10 to USD15 per square inch.

It is currently the crucial outer layer of experimental transparent armor being considered by the US Air Force for the windows of armored vehicles. Other applications include semiconductors and retail fixtures.

Objects are usually formed from pressed, cast or molded powder. The formed objects are then densified by heating in an oven, and polished until transparent. The method of polishing has a substantial positive effect on the armor's impact resistance.^[1]