Single crystal growth of Al13Co4and Al13Fe4from Alrich solutions by the Czochralski method.

Czochralski growth of large metallic alloy single crystals of Al13Co4and Al13Fe4from Alrich solutions has been demonstrated for the first time. A detailed description of all decisive steps of the growth procedure is given with particular emphasis to seeding from a native phase as well as spontaneous nucleation if no seed crystal from a preceding experiment is available. Czochralski growth in a hightemperature solution system requires much lower pulling rates compared to typical growth experiments from the melt and a timedependent temperature program to compensate the change of the liquidus temperature that results from the permanently increasing Al content of the liquid phase. With a given amount of the initial melt, the size of the Al13Co4crystals is limited by the rather narrow temperature range of the Al13Co4primary crystallization window, followed by Al9Co2phase crystallization. In the AlFe system, despite the huge temperature range of equilibrium between Al13Fe4and its Alrich melt, Czochralski growth of Al13Fe4is restricted to higher temperatures due to the limited solubility that leads to mother liquid inclusions even at extremely low pulling rates. © 2008 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim [ABSTRACT FROM AUTHOR]