Sapphire Thermal Conductivity Temperature

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 thermal conductivity temperature.

Thermal coefficient of linear expansion k 1 at 323k. At 25 c 10 14 ohm cm. 756 j kg c at 182 c. 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. Thermal conductivity k strongly depends on temperature and it look like a bell. Wood generally conducts better along the grain than across it. Sapphire as a reference.

From 0 k it is start from zero value and in a particular temperature it reach a maximum peak. 40 w m k 298 k expansion 25 c. Thermal conductivity w m x k at 300k. 25 8 w m c at 70 c.

6 66 x 10 6 parallel to optical axis 5 x 10 6 perpendicular to optical axis. Non porous unlike alumina ceramics. 4 8 x 10 5. 23 0 w m c at 77 c.

9 0 10 6 k 1 90 orientation specific heat capacity. 23 1 parallel to optical axis 25 2 perpendicular to optical axis. 2053 c 3727 f most properties useful to maximum. Virtually unaffected by any solvents or acids at room temperature.

Sapphire properties chemical properties. 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. Resistivity ohm x cm. Good thermal conductivity and high heat resistance.

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. 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. Excellent thermal conductivity at low temperatures allows single crystal sapphire as a transparent material to be used in many diverse fields requiring thermal conduction and heat radiation. 750 j k at 300 k viscosity 2053 c.