摘要
Bi-based 2223 superconducting tapes with high critical current densities were prepared by silver-sheathing method. The relationship between processing, microstructure and property was discussed. The results of critical current density measurement at 77.7K with different applied magnetic field are as follows: Jc=2.87×104A/cm2 (OT) and Jc=4100A/cm2. Jc and Jc-B characteristics were obviously improved with temperature decreasing form 77K to 4.2K. Microstructure observations indicate that intermediate pressing with subsequent heat-treating can lower the porosity of superconductor inside the silver sheath. and reduce the amount and size of non-superconducting phases, leading to the formation of a strong c-axis-oriented texture and the emergence of high dislocation density within the 2223 grains, and consequently the Jc and Jc-B characteristics were improved.
Bi-based 2223 superconducting tapes with high critical current densities were prepared by silver-sheathing method. The relationship between processing, microstructure and property was discussed. The results of critical current density measurement at 77.7K with different applied magnetic field are as follows: Jc=2.87×104A/cm2 (OT) and Jc=4100A/cm2. Jc and Jc-B characteristics were obviously improved with temperature decreasing form 77K to 4.2K. Microstructure observations indicate that intermediate pressing with subsequent heat-treating can lower the porosity of superconductor inside the silver sheath. and reduce the amount and size of non-superconducting phases, leading to the formation of a strong c-axis-oriented texture and the emergence of high dislocation density within the 2223 grains, and consequently the Jc and Jc-B characteristics were improved.
