Growth of YBaCuO mono-domains: growth limit and mono-domains with a diameter up to 7 cm

In order to grow very large mono-domains from a SmBaCuO seed, three growth conditions have been investigated. For a growth with a large overheating or with a thermal gradient, mono-domains with a diameter of 7 cm were easily grown. On the other hand, for a growth in an isothermal furnace, a growth limit has been observed. In this case, the EDS analysis of Y-211 content in the mono-domain shows a Y-211 concentration gradient and a growth Limit when an amount of 48 mol% is reached. In order to limit the Y-211 increase, the time spent in the Liquid phase has to be reduced. This technique enables larger mono-domains to be grown, but the growth is then stopped by parasitic Y-123 grain nucleation in the remaining liquid which blocks the growth front advancement. (C) 1998 Elsevier Science B.V. All rights reserved.