Texturing of high-Tc superconductors

Most of the potential applications of the high-temperature superconductors require large critical currents, much higher than those obtained using a classical sintering process. This paper reviews different processes and corresponding recent results in the field of texturing high-T-c superconductors in order to align and develop the planes where the current flows easily. Different melt-textured growth methods are discussed from both theoretical and practical viewpoints, and the limitations associated with the diffusion and interface phenomena are introduced. Influence of the process parameters, as well as the microstructure of the precursors and the use of additives in order to enlarge the single domain size and to optimise the superconducting characteristics is discussed. Mechanical texturing and texturing under a magnetic field, as well as combination of both processes, are also considered. Recent results, which appear to be an important breakthrough for the industrial development because of the large crystallization rates are also mentioned.