Silver-clad tapes with transport Jc values to 105 A/cm2 at T-4.2K were produced by a powder-in-tube process. Moderate reductions per pass and proper tape thicknesses were essential for producing good conductors. Partial-melt sintering, followed by a solid-state heat treatment, produced microstructures consisting of large, well-aligned 2212 grains and alkaline-earth cuprate phases. The deleterious effects of these second phases were minimized by proper heat treatments, but further reductions in the sizes and concentrations of these phases are needed to improve Jc values substantially. Lithium additions raised Tc, improved flux pinning, and lowered melting points. They offer hope that the presence of alkaline-earth cuprates can be limited through use of low-temperature heat treatments.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry