Torque measurements of textured YBaCuO sintered pellets

The authors present at 4.2 K magnetic torque balance study of a textured sintered YBCO sample produced by pyrolysis using in the thermal treatments an ozone-enriched oxygen atmosphere. The shape of the torque signal as a function of the angle and of the measuring field shows features that are intermediate between those of a standard sintered pellet and those of a single crystal. The anisotropic experimental values of the lower critical field Hc1 compare rather well to those previously found on YBCO single crystals. The intensity of the remaining magnetization, measured after a field cycling procedure, suggests the existence of a strong pinning for H⩾Hc1(c) along the c-axis