Aluminium oxynitride is a clear ceramic made of aluminum, oxygen, and nitrogen. It’s a clear polycrystalline ceramic with a cubic spinel crystal structure composed of nitrogen, oxygen, and aluminum. In the near-ultraviolet, visible, and infrared ranges. It is four times stronger than fused silica glass, eighty-five percent stronger than sapphire, and fifteen percent stronger than magnesium aluminate spinel.
In the near-ultraviolet, visible, and mid-wave-infrared areas of the electromagnetic spectrum, ALON is optically transparent (≥ 80%). It is four times harder than fused silica glass, eighty-five percent harder than sapphire, and roughly 115 percent harder than magnesium aluminate spinel. Since it has a cubic spinel structure, it can be fabricated into transparent windows, plates, domes, rods, tubes, and other forms using conventional ceramic powder processing techniques.
The material remains solid up to 1200°C (2190°F). It has good corrosion resistance and resistance to damage from radiation and oxidation. It is about three times harder than steel of the same thickness.
- Molecular Weight: N/A
- Appearance: White to transparent solid
- Melting Point: ~2150 °C
- Boiling Point: N/A
- Density: 3.696-3.691 g/cm3
- Solubility in H2O: Insoluble
- Crystal Phase / Structure: Cubic, spinel
- Thermal Conductivity: 13 W/mK
- Young’s Modulus: 323 GPa
ALON is the hardest polycrystalline transparent ceramic on the market. It offers potential for applications such as bulletproof, blast-resistant, and optoelectronic windows due to its low weight, distinct optical and mechanical qualities, and resistance to oxidation or radiation. Multiple armor-piercing rounds of up to.50 BMG caliber have been shown to be stopped by ALON-based armor.
ALON is commercially available in sizes as large as 18-by-35-inch (460 mm × 890 mm; 46 cm × 89 cm) monolithic windows.
The created ceramic material is subjected to elevated temperature heat treatment before being ground. After then, the material is polished to make it more transparent. Around 2100°C (3812°F), it loses transparency. Grinding and polishing primarily improve impact resistance, resulting in a material that is 85 percent tougher than sapphire and 15 percent harder than magnesium aluminate spinel.
A sintering additive is added to a source powder that contains less than 0.5 weight percent MgO in this approach. The source powder is then presintered at temperatures ranging from 1550 to 1750°C (2822 to 3182°F) to produce a cubic-phased polycrystalline aluminum oxynitride ceramic with a relative density of greater than 95%. The source powder can be again sintered at 1900°C (3452°F) in order to further increase the relative density of the material. As a result, the porosity is eliminated and the transparency increases to more than 95%.
ALON is utilized for infrared-optical windows, with better than 80% transparency at wavelengths less than 4 micrometers and approaching zero at 6 micrometers. As a result, it has uses as a sensor component, customized IR domes, and laser communications windows. It has also been demonstrated in various semiconductor-related applications as an interface passivation layer.
Some Common applications are –
- Semi-conductor related applications
- Insulators and heat radiation plates
- Optoelectronic devices
- Power and multichip modules
- Translucent ceramics
- High temperature materials and heat sinks
- Break rings
- Thermally conductive filler.