The growth of ruby single crystals

Aleksandar Golubovic, Slobodanka Nikolic, Stevan Djuric, Andreja Valcic
2005 Journal of the Serbian Chemical Society  
Ruby (Cr:Al 2 O 3 ) single crystals were grown by the Czochralski technique in an argon atmosphere. The critical crystal diameter d c = 1.0 cm and the critical rate of rotation w 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. H 3 PO 4 at 593 K for an exposure of 3 hours was determined. Conc. H 3 PO 4 at 523 K for an exposure of 3 h was found to be a suitable etching
more » ... 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.
doi:10.2298/jsc0501087g fatcat:xa7xthfcv5f2lahunhq4e7dyau