NIST Standard Reference Database 30
Last Update to Data Content: 2002
"Temperature Dependence of the Thermal Diffusivity/Conductivity of Aluminum Nitride," T.B. Jackson, K.Y. Donaldson, and D.P.H. Hasselman, Journal of the American Ceramic Society, Vol. 73 [8], pp. 2511-2514 (1990), published by American Ceramic Society.Language: English
"Samples were sintered from high-purity AlN powder with 4 wt% Y2O3 added as a sintering aid and oxygen-getter. The AlN and Y2O3 powders were combined in a plastic jar with Al2O3 grinding media and n-hexane and milled for 1 h. After removal of the liquid, cylindrical pellets were uniaxially pressed at 30 MPa and isostatically pressed at 200 MPa. The pellets were heated to 1850 °C and held at that temperature for 10 h in a flowing nitrogen atmosphere. The furnace used was of the graphite resistance-heated type."
"The samples were coated with a layer of gold with thickness of approximately 0.1 µm to prevent direct transmission of the laser pulse. The gold coating, in turn, was coated with a thin layer of colloidal carbon to enhance the optical coupling between the sample and the laser pulse and to enhance the emissivity... Briefly, at room temperature (18 °C), the specimens were placed in a specimen holder held directly against the sapphire window of the detector, to ensure a maximum detector signal. At temperatures up to 300 °C, the specimens were placed in a small heater located approximately 200 mm from the detector. The IR radiation from the specimen was focused onto the detector element by means of a sapphire lens. The thermal diffusivity was measured using laser pulse energies of approximately 20, 33, 48, and 55 J, attenuated by 0%, 60%, and 78%. ... The increase in specimen thickness with temperature due to thermal expansion was accounted for using a value for the coefficient of thermal expansion of 3.5 x 10-6 °C-1."
"The specific heat was measured by differential scanning calorimetry on a specimen prepared concurrently with the thermal diffusivity specimens." No additional measurement details were noted.
| Temperature ( °C ) | Density ( g/cm3 ) | Specific Heat ( J kg-1 K-1 ) |
|---|---|---|
| 18 | 3.257 | 725 |
| 134 | 3.253 | 906 |
| 206 | 3.251 | 975 |
| 252 | 3.249 | 1020 |
| 304 | 3.247 | 1052 |
| Temperature ( °C ) | Density ( g/cm3 ) | Thermal Conductivity ( W m-1 K-1 ) |
|---|---|---|
| 18 | 3.257 | 208 |
| 134 | 3.253 | 156 |
| 206 | 3.251 | 128 |
| 252 | 3.249 | 106 |
| 304 | 3.247 | 92 |
| Temperature ( °C ) | Density ( g/cm3 ) | Thermal Diffusivity ( cm2 s-1 ) |
|---|---|---|
| 18 | 3.257 | 0.88 |
| 134 | 3.253 | 0.53 |
| 206 | 3.251 | 0.41 |
| 252 | 3.249 | 0.32 |
| 304 | 3.247 | 0.27 |