Magnetic levitation force of bulk YBaCuO pieces as a function of texture

摘要

Very well textured YBaCuO forms can be produced by means of seed crystals implanted in an YBaCuO melt. Narrow distributions of the directions (FWHM < 6 degrees) of the c-axes of the crystalline grains as well as the a- and b-axes, respectively, are required for this purpose. Small angles between the c-axes of adjacent grains, and small angles between the a- and b-axes, respectively, of the neighbors, constitute but small obstacles in the path of the superconducting current induced. If the entire volume of the melt-textured forms, in this case YBaCuO cylinders, is well textured, and if no random volume fractions remain, a maximum inducible superconducting current in the superconductor can be achieved and, thus, a maximum magnetic repellent force against the inducing permanent magnet, can be attained. This ensures maximum magnetic levitation force for a superconducting self-stabilizing magnetic bearing. [References: 13]