Speaker
Yanwei Ma
(Institute of Electrical Engineering, Chinese Academy of Sciences)
Description
122 type pnictide superconductors are of particular interest for high-field applications because of their large upper critical fields Hc2 (> 100 T), low anisotropy γ (< 2) and the materials and processes to fabricate wires appear to be relatively inexpensive. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. Here we report our recent achievement in the developing Sr0.6K0.4Fe2As2 tapes with transport Jc up to 1.2 ×10^5 A/cm^2 at 10 T and 4.2 K. More importantly, the field dependence of Jc turns out to be very weak, such that in 14 T the Jc still remains ~ 1.0×10^5 A/cm^2. These Jc values are the highest ever reported so far for iron-pnictide wires and tapes, and have surpassed the threshold for practical application. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications.
Author
Yanwei Ma
(Institute of Electrical Engineering, Chinese Academy of Sciences)