Title :
Engineering the precompression of Bi,Pb(2223): the influence of the geometry of the metallic matrix on the mechanical properties of tapes
Author :
Passerini, Reynald ; Dhallé, Marc ; Witz, Grégoire ; Seeber, Bernd ; Flükiger, René
Author_Institution :
Group of Appl. Phys., Geneva Univ., Switzerland
fDate :
3/1/2001 12:00:00 AM
Abstract :
At relatively low tensile strain (ε) levels, Bi,Pb(2223) tapes show a strain insensitive plateau In their Ic(ε) behavior. The “Irreversible Ic Reduction Model” explains this regime as due to the irreversible damage caused by the precompression of the ceramic filaments by the metal matrix. In this paper we investigate whether this damage occurs predominantly during the cool-down from the reaction temperature to room temperature, or during the cryogenic refrigeration. Furthermore, we present Ic(ε) data on a range or tapes with different superconductor-to-matrix ratio and different tape geometry, showing how these factors influence the precompression. A modification of the “Irreversible Ic Reduction Model” is proposed to take into account “connected-grains” domains in the Ic (ε) behavior
Keywords :
bismuth compounds; calcium compounds; critical currents; high-temperature superconductors; internal stresses; lead compounds; silver; strontium compounds; superconducting tapes; (BiPb)2Sr2Ca2Cu3O 10-Ag; 20 C; Bi,Pb(2223); Ic; Irreversible Ic Reduction Model; ceramic filaments; connected-grains; cool-down; cryogenic refrigeration; irreversible damage; low tensile strain; mechanical properties; metallic matrix; precompression; reaction temperature; room temperature; strain insensitive plateau; superconductor-matrix ratio; tape geometry; tapes; Bismuth compounds; Capacitive sensors; Ceramics; Cooling; Filling; Geometry; Mechanical factors; Temperature measurement; Tensile strain; Ultrasonic variables measurement;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
