Gj. Schmitz et O. Kugeler, ISOTHERMAL PRODUCTION OF UNIAXIALLY TEXTURED YBCO SUPERCONDUCTORS USING CONSTITUTIONAL GRADIENTS, Physica. C, Superconductivity, 275(3-4), 1997, pp. 205-210
Uniaxially textured samples of bulk (RE)BaCuO were melt-grown in an is
othermal furnace utilizing the influence of different rare earth compo
unds on the peritectic temperature of (RE)BaCuO. A suitable geometric
arrangement of different (RE)Ba2Cu3Ox compounds during heat treatment
leads to a specific diffusion profile of the respective RE elements. A
ccording to the distinct peritectic temperatures of the different RE-s
ystems, a monotonous decrease in peritectic temperature could be estab
lished. This gradient determines the direction of crystallization duri
ng isothermal cooling and moreover governs the selection mechanism res
ulting in preferred c-axis growth. In contrast to texturing samples in
external gradients, the use of a layered structure of different (RE)B
a2Cu3Ox compounds allows a tailored texturing or textured coating even
of complex shaped products and opens up a variety of interesting pers
pectives for the production of long length wires and perhaps even of l
arge grained bulk material.