Phase compatibility and preparation of composite

Abstract

The chemical compatibility of the phase with was investigated, and a composite superconductor was prepared. Ceramic processing of the corresponding oxide and carbonate mixture at led to the two-phase species , while the solubility of In in Bi-2212 was less than 5 mol%. At indium appeared to be less soluble in the BSCCO melt, instead being concentrated in fine grains of phase suspended in the liquid. By slow crystallization of the melt the composite was obtained. The In-rich phase formed micron-sized rods which were both randomly embedded in Bi-2212 lamellas and agglomerated on the Bi-2212 grain boundaries. The presence of the indium-based surplus did not prevent Bi-2212 phase formation, had minor effect on and resulted in increase of flux pinning at K.

Synthesis and Crystal Structure of Sr2ScBiO6

“…Recently, by doping the Bi Sr CaCu O >V superconductor with scandium oxide we observed the formation of a new phase with composition Sr ScBiO ; this phase coexisted with the superconductor and its melt (10). In the present work we consider the synthesis of pure Sr ScBiO and determine its crystal structure, oxygen nonstoichiometry, and thermal stability.…”

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

“…At higher temperature (usually above 20 K) these centres cannot pin the vortices, and the J c is determined by the number of pinning sites with high energy which is connected with the inclusion concentration. Therefore, in many cases the specimens with the inclusions exhibit higher J c at increased temperature (30-60 K) while at T < 10 K the effect of the inclusions is not revealed [3,6,[10][11][12].…”

“…Different ways of inclusion formation were investigated. For instance, fine precipitates of the secondary phases were created by partial decomposition of the single-phase superconductor [3,6]; MgO was introduced in the form of micro-or nanosize whiskers and grains [5,[7][8][9]; submicron inclusions of complex metal oxides were formed in the Bi-2212 matrix via processing of the homogeneous precursors [10][11][12][13].…”

Microcomposites based on superconducting cuprates

“…Synthesis from nitrate solutions gives the composite containing elongated indate particles of size 165 mm, which are partially agglomerated in-between the Bi2212 lamellae. 172 Synthesis from a glassy oxide causes the formation of more anisotropic indate particles, which are much less agglomerated. 215 One can expect that an anisotropic particle placed at a large angle with respect to the front of the growing crystal will be more readily trapped by the crystal compared to an equiaxial particle.…”