Aluminum nitride (AlN) is a promising material for heat sinks and microelectronic applications because of the advantages of high thermal conductivity, high mechanical strength, good electrical insulation, low dielectric constant and low thermal expansion coefficient. However, the difficulties in forming complex-shaped parts with a high thermal conductivity have retarded the wide applications of AlN ceramic. Herein, TechCeramic adopts the powder injection molding technology to fabricate complex-shaped AlN parts.
The use of rare earth metal fluoride as a sintering aid, rather than a rare earth metal oxide, has two main advantages: First, the rare earth metal fluoride has a lower melting point than the rare earth metal oxide, and it forms liquid phase at a low temperature. The phase promotes the rearrangement and densification of the particles, making AlN ceramic with high strength. Second, during the sintering process, the fluoride will be decomposed and converted into oxides, thereby absorbing the oxygen, reducing the oxygen content of the aluminum nitride, and reducing the amount of liquid phase, thereby improving the heat conductivity.
|Bulk Density g/cm3||3.32||3.33|
|Apparent Porosity %||0||0|
|Flexural Strength MPa||400||300|
|Young’s Modulus of Elasticity GPa||320||320|
|Thermal Expansion 20 – 1000°C, 10-6 K-1||4.8||4.6|
|Thermal Conductivity (25°C) W/m°K||170||210|
|Dielectric Constant 1 MHz||8.8||8.9|
|Dielectric Strength kV/mm||31||27|