Hot pressing to enhance the transport Jc of Sr0.6K0.4Fe2As2 superconducting tapes

Abstract

High-performance Sr0.6K0.4Fe2As2 (Sr-122) tapes have been successfully fabricated using hot pressing (HP) process. The effect of HP temperatures (850-925 C) on the c-axis texture, resistivity, Vickers micro-hardness, microstructure and critical current properties has been systematically studied. Taking advantage of high degree of c-axis texture, well grain connectivity and and large concentration of strong-pinning defects, we are able to obtain an excellent Jc of 1.2x10^5 A/cm^2 at 4.2 K and 10 T for Sr-122 tapes. More importantly, the field dependence of Jc turns out to be very weak, such that in 14 T the Jc remains ~1.0x10^5 A/cm^2. These Jc values are the highest ever reported so far for iron-pnictide wires and tapes, achieving the level desired for practical applications. Our results clearly strengthen the position of iron-pnictide conductors as a competitor to the conventional and MgB2 superconductors for high field applications.

21 pages, 7 figures

References in corpus (5)

• Superconductivity up to 37 K in (A1-xSrx)Fe2As2 with A=K and Cs
• Advantageous grain boundaries in iron pnictide superconductors
• High intergrain critical current density in fine-grain (Ba0.6K0.4)Fe2As2 wires and bulks
• Fishtail effect and the vortex phase diagram of single crystal Ba0.6K0.4Fe2As2
• Electromagnetic, atomic-structure and chemistry changes induced by Ca-doping of low-angle $YB{a}_{2}C{u}_3{O}_{7-\delta }$ grain boundaries

Cited by in corpus (7)

• High transport current superconductivity in powder-in-tube Ba0.6K0.4Fe2As2 tapes at 27 tesla
• Fabrication and Transport Properties of 100 m Class Sr0.6K0.4Fe2As2 Wires and Pancake Coils
• Enhancement of critical current densities in (Ba,K)Fe2As2 wires and tapes using HIP technique
• Fabrication of small superconducting coils using (Ba,A)Fe2As2 (A: Na, K) round wires with large critical current densities
• Enhancement of critical current density in (Ba,Na)Fe2As2 round wires using high-pressure sintering
• Synthesis of CaKFe${}_4$As${}_4$ bulk samples with high critical current density using a spark plasma sintering technique
• Large transport Jc in Cu-sheathed Sr0.6K0.4Fe2As2 superconducting tape conductors