Fabrication of Bi-2212-Ag composite solenoid type superconducting magnet by partial melt process under high

✍ Scribed by K. Shibutani; T. Hase; S. Hayashi; M. Shimada; R. Ogawa

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 446 KB
• Volume: 216
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(95)00483-1

✦ Synopsis

Partial melt process under high oxygen partial pressure (Po2) has been attempted to obtain a well-aligned structure in Bi-2212 Ag composite tapes. Critical current density (J~) of Bi-2212 Ag composite tapes increased from 4.5 x 104 to 2.2 × 105 A/cm z at 4.2 K in zero magnetic field with increasing Po2 from 0.1 to 1.0 bar. This process was also effective to improve J~ of round and rectangular conductors. These results were explained by the idea that crystallization of the Bi-2212 system started at the interface between the liquid phase and the oxygen-rich gaseous phase. Jc of the round and rectangular conductors in short length reached 7.8 x 103 and 1.4 x 104 A/cm 2 in 21 T at 4.2 K, respectively. Fabrication of a solenoid type magnet has been attempted using a rectangular conductor under Po: = 2.4 bar. J¢ of this solenoid type magnet reached 4.2 x 104 A/cm 2 under generating a self-magnetic field of 0.89 T at 4.2 K.