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