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Aluminium Oxide ( ά? -Al2O3 )
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Aluminium oxid: Al2O3-Cr,
Al2O3-Flux, Al2O3-Cr Flux
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Aluminium oxid: Al2O3 Korundum
and Ruby - Crystals
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Aluminium oxid: Al2O3 : Cr
Ruby rod
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Aluminium oxid Al2O3
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Aluminium oxid Al2O3
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Crystal properties
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Crystal growth method
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Czochralski, HEM,Verneuil
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Crystal growth orientation
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(0 001),(1102),(1012),(1010)
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Maximum size
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7 inch diameter
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Variations
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Doped crystals (Fe, Nb, Ti, W,Ta,V,Cr)
Other dopands on request
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Crystallographic properties
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Hexagonal / Rhombohedric
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Crystallographic structure
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a = 4.77 A
c = 13.04 A
a : c = 1 : 2.734
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a = 4.758 Å
c = 12.991 Å
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Mineralogical synonyms
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Sapphire, Corundum
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Twinning structure
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Twinfree
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Colour
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Colourless
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Density
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3.98 g/cm3
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Melting point
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2052 °C
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Hardnes
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9 (Mohs)
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Thermal expansion coefficient
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5.4 * 10_6 K_1
6.2 * 10_6 K_1
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|| c-axis
^ c-axis
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RT
RT
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Dielectric constant
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9.4
11.5
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| c-axis
^ c-axis
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RT
RT
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Physical properties cont.
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Dielectric loss tangent (10GHz)
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3.0 * 10_5
8.6 * 10_5
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^ c-axis
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RT
RT
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Dielectric constant:
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1016 W/cm
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RT
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Optical properties
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Transmission range
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0.2 to 6.0 mm
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Refraction index:
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nd = 1.8336
nd = 1.58638
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at 265 nm
at 5.6 mm
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Dispersion
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0.011
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Standard orientations
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(0001),(1102),(1012),(1010)
Other orientations on request
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List of Refractive index, ordinary ray at 24 °C (Al2O3)
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Optical properties refraction index Aluminium oxide
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Wavelength (µm)
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Refractive index
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0,28035
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1,8243
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0,289036
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1,8195
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0,29673
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1,8159
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0,30215
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1,8135
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0,31300
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1,8091
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0,33415
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1,8018
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0,34662
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1,7981
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0,36105
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1,7945
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0,36501
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1,7936
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0,39064
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1,7883
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0,40466
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1,7858
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0,43583
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1,7812
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0,54607
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1,7708
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0,57696
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1,7688
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0,57907
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1,7687
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0,64385
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1,7655
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0,70652
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1,7630
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0,85212
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1,7588
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0,89440
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1,7579
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1,01398
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1,7555
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1,12866
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1,7534
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1,36728
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1,7494
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1,39506
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1,7489
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1,52952
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1,7466
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1,69320
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1,7437
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1,70913
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1,7434
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1.81307
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1,7414
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1.97010
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1,7383
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2,15260
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1,7344
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2,24929
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1,7323
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2,32542
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1,7306
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2,43740
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1,7278
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3,24320
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1,7044
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3,26660
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1,7036
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3,30300
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1,7023
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3,29300
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1,7015
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3,41880
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1,6982
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3,50780
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1,6950
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3,70000
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1,6875
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4,25800
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1,6637
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4,95400
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1,6266
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5,14560
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1,6151
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5,34900
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1,6020
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5,41900
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1,5973
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5,577
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1,5864
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