Research Progress of Bi-2212 Superconducting Wire

The Bi₂Sr₂CaCu₂O_8+x (Bi-2212) superconductor exhibits exceptionally high critical transition temperature and upper critical magnetic field, along with outstanding current-carrying capabilities under high magnetic fields. These characteristics make Bi-2212 an ideal material for high-field superconducting magnet fabrication. Furthermore, Bi-2212 stands as the only high-temperature superconductor that can be fabricated into isotropic round wires, significantly simplifying the manufacturing processes of Bi-2212 superconducting cables and coils. Consequently, Bi-2212 demonstrates substantial application potential in high-field domains such as nuclear magnetic resonance, magnetically levitated train, and future controlled nuclear fusion devices. This article briefly describes the fabrication processes of Bi-2212 multifilamentary wires, including the powder-in-tube method, preparation techniques for precursor powders, wire processing technologies, and partial melting heat treatment processes. Furthermore, the key factors influencing the critical current density of Bi-2212 superconducting wires are summarized and strategies for enhancing their critical current density are discussed.