2005 Volume 46 Issue 5 Pages 930-934
Growth process and solidification structures of REBCO (RE=Y, Nd etc.) fabricated by conventional unidirectional solidification and infiltration-growth method were studied analytically and numerically to clarify growth and structure-formation mechanism of faceted 123 crystals. The change in freezing front temperature of 123 phase during unidirectional solidification and the critical transition conditions of macrostructures from columnar to equiaxed structures were analyzed by using the growth rate (R)-undercooling (ΔT) and the cooling rate (Vc)-ΔT relations. The formation process of microstructure of faceted 123 crystal was simulated by two-dimensional numerical method. The results on the formation of solidification structures obtained by the above analysis and simulation showed good agreements with the experimental ones.
