The growth of ruby single crystals
2005 ◽
Vol 70
(1)
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pp. 87-95
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Keyword(s):
X Ray
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Ruby (Cr:Al2O3) single crystals were grown by the Czochralski technique in an argon atmosphere. The critical crystal diameter dc = 1.0 cm and the critical rate of rotation ?c = 20 rpm were calculated by equations of the hydrodynamics of the melt. The rate of crystal growth was experimentally obtained to be 2.7 mm/h. For chemical polishing, conc. H3PO4 at 593 K for an exposure of 3 hours was determined. Conc. H3PO4 at 523 K for an exposure of 3 h was found to be a suitable etching solution. The lattice parameters a = 0.47627(6) nm and c = 1.301(1) nm were determined by X-ray powder diffraction. The obtained results are discussed and compared with published data.
2004 ◽
Vol 69
(6)
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pp. 493-502
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1999 ◽
Vol 64
(9)
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pp. 553-561
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Keyword(s):
2004 ◽
Vol 69
(12)
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pp. 1121-1128
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2011 ◽
Vol 76
(11)
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pp. 1561-1566
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Keyword(s):
1999 ◽
Vol 64
(10)
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pp. 637-646
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