Reversing radial segregation and suppressing morphological instability during vertical Bridgman crystal growth by rotation
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چکیده
During vertical Bridgman growth of an alloy crystal, local accumulation of solute at the interface center due to buoyancy often causes formation of a deep depression or pit and accelerates morphological instability. Through visualization of the freezing interface during directional solidification of succinonitrile containing ethanol on a rotating table, it was shown that rotation about the ampoule axis might reverse solute distribution and remove pit formation. Simulation was also conducted to explain the observations. r 2002 Elsevier Science B.V. All rights reserved. PACS: 44.25.+f; 47.27.Te; 81.10.Fq; 02.60.c6; 02.70.Fj
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تاریخ انتشار 2002