Jin-Ho Joo

The effect of silver (Ag) solubility on microstructure and superconducting properties of YBa2Cu3−xAgxO7−δ (0≤x≤0.5) superconductors has been evaluated. The solubility limit of Ag for copper sites in YBCO at ambient conditions (room temperature, atmospheric pressure) was evaluated to be x≂0.06. Analysis revealed the Ag content (x) of YBCO grains to be lower than the nominal Ag content (xn) used for fabrication, probably due to processing-related problems. Part of the Ag used for fabrication segre

The effects of thermomechanical treatment, starting composition, and Ag addition on microstructure and corresponding critical current density (Jc) of Ag sheathed Bi1.8Pb0.4Sr2Ca2.2Cu3Ox (BSCCO) superconductor tapes made by a powder-in-tube technique have been studied. It was observed that for sintering in a 10% flowing oxygen atmosphere, 835-840 degrees C is the optimum processing temperature range for improved Jc. Above this temperature range, although the grain alignment increases, the content

Stabilization of high-temperature phases such as tetragonal ( t -) or cubic phases has been a pivotal issue for technological applications of polymorphic ZrO 2 . In this work, we fabricated ZrO 2 /Si films using a sol–gel deposition route and investigated the phase transformation, microstructural evolution, surface morphological changes, and interfacial chemical structures by thermal annealing. The ZrO 2 precursor solution was prepared using a zirconium acetylacetonate, coated, dried on Si subst