论文信息 - The influence of initial composition and oxygen partial pressure on the properties of melt-textured NdBaCuO

The influence of initial composition and oxygen partial pressure on the properties of melt-textured NdBaCuO

Abstract The influence of several admixtures on the microstructure formation and the superconducting properties is explained on the base of phase-equilibrium considerations. Conditions are derived which permit the stabilization of Ba rich Nd-123 phase to occur which is a precondition for preparing textured NdBaCuO materials with Tc > 90 K and a sufficient high jc. A melt-textured bulk material with Tc = 91 K and jc(77 K, 0 T, B ∥c) = 21.8 kA/cm2 was produced at p(O2) ≈ 100 Pa using an initial mixture consisting of NdBa2Cu3O7−δ and Nd2BaO4.

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