Manufacturing method of bulk Y-Ba-Cu-O superconductor having high transport limiting current density

摘要

PURPOSE: To provide a bulk YBa₂Cu₃O_x superconductor to conduct the high continuous DC current by achieving the compaction and heat treatment under the prescribed condition to the mixture of Y₂O₃, BaO₂ and CuO of the prescribed ratio. ;CONSTITUTION: Y₂O₃, BaO₂ and CuO are mixed at the ratio of Y:Ba:Cu=1:2:3, the mixture is compacted to the pellet of 2.54 cm in diameter and 0.5-0.8 cm in thickness, and annealed for 24 hours at the temperature of 940°C, and then, the temperature is dropped to the room temperature. The pellet is pulverized into fine powder, the compacted pellet is annealed for 48-72 hours at 980°C, and the temperature is dropped to 550°C, and kept at this value for 10-20 hours, and then, dropped to 400°C in eight hours, kept at this value for 10-20 hours, and then, dropped to the room temperature. The pellet is charged into a furnace, and kept at the temperature of 1100°C for 10 minutes, the temperature is dropped to 1030°C in 20 minutes, and then, dropped to 980°C for 50 hours. The pellet is kept at 980°C, the temperature is dropped to 900°C in 16-30 hours, dropped to 550°C in six hours, then, kept at 550°C for 10-20 hours, dropped to 400°C in eight hours, and is kept at 400°C for 10-20 hours, and then, dropped to the room temperature.;COPYRIGHT: (C)1992,JPO