Aluminum Nitride Ceramics are ceramics with aluminum nitride (AIN) as the main crystal phase.AlN crystals use [AIN4] tetrahedrons as the structural unit covalent bond compounds, with a wurtzite structure, belonging to the hexagonal system. Chemical composition: AI 65.81%, N 34.19%, specific gravity 3.261g/cm3, white or off-white, single crystal is colorless and transparent, the sublimation decomposition temperature under normal pressure is 2450°C. A high-temperature heat-resistant material. Thermal expansion coefficient (4.0-6.0)X10-6/°C. Polycrystalline AIN thermal conductivity of 260W / (m.k), 5-8 times higher than aluminum oxide, so the heat and shock resistance, can withstand extremely hot 2200 °C. In addition, aluminum nitride has the property of being free from attack by molten aluminum and other molten metals and gallium arsenide, and particularly has excellent corrosion resistance to molten aluminum liquid.application1. Aluminum nitride powder has high purity, small particle size and large activity, and is the main raw material for manufacturing high thermal conductivity aluminum nitride ceramic substrates.2. Aluminum nitride ceramic substrate has high thermal conductivity, low coefficient of expansion, high strength, high temperature resistance, chemical resistance, high resistivity and low dielectric loss. It is an ideal large-scale integrated circuit heat-dissipating substrate and packaging material.3, aluminum nitride high hardness, more than traditional alumina, is a new type of wear-resistant ceramic materials, but due to high cost, can only be used for serious wear and tear.4. Using AIN ceramics for heat resistance, melt erosion and thermal shock resistance, GaAs crystal crucibles, Al evaporating dishes, magnetic fluid power generation devices, and high-temperature turbine corrosion resistance components can be fabricated, and their optical properties can be used as infrared windows. Aluminum nitride films can be made into high-frequency piezoelectric elements, VLSI substrates, etc.5, aluminum nitride heat, corrosion resistance to molten metal, acid stability, but easily eroded in alkaline solution. The exposure of AINs neonatal surface to moist air will generate a very thin oxide film. Using this feature, it can be used as a crucible and cast mold material for metal smelting of aluminum, copper, silver, lead, and the like. AIN ceramics have good metallization properties and can be used as a substitute for toxic oxidized enamels in the electronics industry.
Materials mechanical properties and thermal conductivity dielectric properties.
|Aluminum Nitride Ceramics Properties
||Thermal expansion coefficient