Abstract
A method for controlled grain alignment in YBaCuO superconductors has been developed. The processing conditions to preferentially nucleate and grow the a--b plane facets along the sample length have been studied. A longitudinal temperature gradient significantly higher than the lateral gradient is required to force the grain nucleation at the tip instead of at the sides of the sample. However, a suitable sample geometry is required to control the site of nucleation and the direction of subsequent grain growth. J sub c measurements across a--b planes show the importance of aligning the a--b planes along the length of the melt-processed superconductor.