Formation of Bi-2212-based composites with submicrometre-grained (Sr, Ca)SnO₃

Abstract

Phase assemblage was investigated in the Bi-Sr-Ca-Cu-Sn-O system at temperatures of Bi-2212 phase crystallization. It is found that the Sr 1−x Ca x SnO 3 phase (x = 0.1-0.2) is compatible with Bi-2212 as well as with Bi-2201, CuO, alkaline-earth metal cuprates and bismuthates. The solubility of Sn in Bi-2212 is limited to low values. The superconducting composites Bi-2212-(Sr, Ca)SnO 3 were prepared by melt crystallization using single precursor and mixed precursor routes. The materials consisted of Bi-2212 matrix with submicron (Sr, Ca)SnO 3 grains included in Bi-2212 lamellas and agglomerated in between. The composites exhibited enhanced flux pinning at T = 60 K, while at 5 K the effect of (Sr, Ca)SnO 3 addition was not revealed.

Enhancement of critical current density and flux pinning properties of Gd-doped (Bi, Pb)-2212 superconductor

“…[3][4][5][6][7][8][9] It has been found that the Pb doping at Bi site in Bi-2212 increases the c-axis conductivity by more than one order of magnitude and reduces the anisotropy. The main advantages of Bi-based systems are their layered structure and hence texturing can be easily induced in it.…”

Effects of SnO on growth and physical properties of BSCCO whiskers

“…In the BSCCO system, it has some controversial results, in which Kazin et al 31 suggested that Sn reduced the magnetism in the system prepared but Li et al 44 and Seyoum et al 28 suggested that Sn increased the pinning property and the J c of the system. The authors' study showed that the pinning behaviour in Bi-2212 doped by SnO decreased as obtained by Kazin et al, 31 and the authors believed that the superconductivity of the prepared system was destroyed at low magnetic field values. Magnetisation critical current density J cmag of the whisker was calculated using the Bean model 46 and found to be 13610 3 at 5 K. We believe that Sn ions more probably incorporate into interstitial sites in the BSCCO-2212 unit cell, which can cause the blocking of the transport of carriers between Bi-O and Cu-O layer and hence decrease J c .…”

“…Marine et al 45 reported that Sn doped YBCO exhibited less magnetism with applied fields than that of undoped sample. In the BSCCO system, it has some controversial results, in which Kazin et al 31 suggested that Sn reduced the magnetism in the system prepared but Li et al 44 and Seyoum et al 28 suggested that Sn increased the pinning property and the J c of the system. The authors' study showed that the pinning behaviour in Bi-2212 doped by SnO decreased as obtained by Kazin et al, 31 and the authors believed that the superconductivity of the prepared system was destroyed at low magnetic field values.…”

“…However, Sn ions in the system caused a decrease in the critical current density J c and magnetisation of material. 28,31,32 In this work, the authors successfully fabricated the whiskers on the Bi 2 Sn 1 Sr 2 Ca 2 Cu 3 O 10zx (Bi 2 Sn 1 -223) composition using the glass precursor method and investigated their thermal, electrical and magnetic properties. The phase evaluation of the obtained material with increasing heat treatment temperature was investigated with SEM and X-ray diffraction (XRD) experiments.…”

Anorganische Festkörperchemie im Konzert der Materialforschung

“…Die Entdeckung der blauviolett‐ bis magentafarbenen Pigmente auf Apatitbasis17) (A5(PO4)3(OH, CuOx), A = Ca, Sr, Ba) entspricht dagegen einem Treffer im Lotto: Der Apatit war als eine der wenigen Verbindungen erkannt worden, die in der Schmelze von Bismutcuprat‐Supraleitern thermodynamisch stabil sind, und sollte feinteilig in das supraleitende Material eingebracht werden, um so die Flussschläuche zu verankern und damit die Stromtragfähigkeit des Supraleiters zu erhöhen 18. (Bei Supraleitern 2.…”