Effect of TaC Microadditions on the Microstructure and Properties of (Bi,Pb)2Sr2Ca2Cu3O10 + x Superconducting Ceramics

Information-theoretical approaches are used to assess the effect of nanocrystalline TaC microadditions on the thermodynamic conditions of microstructure evolution in (Bi,Pb)2Sr2Ca2Cu3O10 + x superconducting ceramics. Optimization analysis of property–structure–composition relationships indicates that the introduction of TaC makes it possible to raise the midpoint transition temperature Tc of the ceramics by 4 K and their 77-K critical current density jc by 1000 A/cm2 . It is shown using information interpretation of multifractal formalism that the optimal TaC content is about 0.14 wt %. At this doping level, the expected increase in Tc is 8 K, and that in jc is 1300 A/cm2 . The crystallite and pore substructures in Bi-2223 ceramics are shown to be correlated.