Title :
Study of powder density, Ag:superconductor ratio, and microhardness of BSCCO-2212 Ag-sheathed wires and tapes during wire drawing and rolling
Author :
Karuna, M. ; Parrell, J.A. ; Larbalestier, D.C.
Author_Institution :
Appl. Supercond. Center, Wisconsin Univ., Madison, WI, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
Densification of Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub x/ (BSCCO-2212) powder cores in Ag-clad wires and tapes has been studied as a function of strain and initial packing density. Density was measured directly by etching away the silver and weighing the remaining core. A universal feature in both wires and tapes was the attainment of maximum densities (/spl sim/80%) at intermediate strains of /spl sim/4. The linear correlation between microhardness and density found for round wires breaks down for rolled tapes, apparently because the core separates into dense locks separated by cracks.<>
Keywords :
bismuth compounds; calcium compounds; densification; drawing (mechanical); high-temperature superconductors; microhardness; multifilamentary superconductors; powder technology; rolling; silver; strontium compounds; superconducting tapes; Ag-sheathed tapes; Ag-sheathed wires; Ag:superconductor ratio; Bi/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O-Ag; cracks; densification; drawing; high temperature superconductor; initial packing density; microhardness; powder density; rolling; strain; Billets; Bismuth compounds; Capacitive sensors; Conductors; Density measurement; Fabrication; High temperature superconductors; Powders; Superconducting filaments and wires; Wire drawing;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
