Sapphire Thermal Conductivity Temperature

From 0 k it is start from zero value and in a particular temperature it reach a maximum peak.

Sapphire thermal conductivity temperature.

Single crystal single crystal sapphire is used for various kinds of vacuum equipment windows in excellent thermal conductivity at low temperatures allows single crystal sapphire as a. Non porous unlike alumina ceramics. 4 5 10 6 k 1 and 1000 c. 25 8 w m c at 70 c.

23 0 w m c at 77 c. Good thermal conductivity and high heat resistance. It is also used as an insulation material and microwave window. No significant thermal resistance due to bonded inter face was found from this measurement.

Wood generally conducts better along the grain than across it. Obtained thermal conductivity reaches κ 1 104 w m k in temperature range of t 20 30 k which is a planned operating temperature of a cryogenic mirror of the large scale cryogenic grav itational wave telescope. Sapphire properties chemical properties. Thermal coefficient of linear expansion k 1 at 323k.

23 1 parallel to optical axis 25 2 perpendicular to optical axis. Virtually unaffected by any solvents or acids at room temperature. 6 66 x 10 6 parallel to optical axis 5 x 10 6 perpendicular to optical axis. Thermal electrical and optical ir transmission vs wavelength 500 c 20 c 1000 c 0 0 2 3 4 5 6 10 20 30 40 50 60 70 80 90 100 wavelengths microns transmission dielectric constant vs temperature parallel to c axis perpendicular to c axis 0 200 400 600 800 1000 1200 8 9 10 11 12 13 14 15 16 17 temperature c dielectric constant.

Thermal conductivity k strongly depends on temperature and it look like a bell. 750 j k at 300 k viscosity 2053 c. Thermal conductivity w m x k at 300k. Sapphire is a notable example of variable thermal conductivity based on orientation and temperature with 35 w m k along the c axis and 32 w m k along the a axis.

At 25 c 10 14 ohm cm. 2053 c 3727 f most properties useful to maximum. 40 w m k 298 k expansion 25 c. 9 0 10 6 k 1 90 orientation specific heat capacity.

Some etching by hot phosphoric acid and strong caustics at temperatures exceeding 600 c 800 c thermal properties. Single crystal sapphire is used as a material for substrates in super high frequency regions. 4 8 x 10 5. Resistivity ohm x cm.