Production of optimized melt-textured volume samples of high temperature superconductors comprises preparing the starting material for the green body, mixing, molding and sealing, and then melt-texturing

摘要

Optimized melt-textured volume samples based on a high temperature superconductor are produced by preparing the starting material for the green body, mixing, molding and sealing, and then melt-texturing. Optimized melt-textured volume samples based on a high temperature superconductor are produced by: (A) preparing the starting material for the green body so that the melt-textured body consists of at least 50 wt.% SmBCO or NdBCO, in which Sm0.8-1.8Ba2-y1Cu3-z1O7-x1 (where x1 = 0-0.5; y1 = -0.2-0.2; z1 = -0.3-0.3), or Nd0.8-1.8Ba2-y2Cu3-z2O7-x2 (where x2 = 0-0.5; y2 = -0.2-0.2, and z2 = -0.3-0.3) are used as the starting powder forming a matrix to which is added: (a1) 0-45 wt.% Sm0.8-1.8Ba2-y1Cu3-z1O7-x1 (where x1 = 0-0.5; y1 = -0.2-0.2; z1 = -0.3-0.3), and 0-45 wt.% Sm-211 and 0-50 wt.% Nd-422 and/or 0-45 wt.% Nd0.8-1.8Ba2-y2Cu3-z2O7-x2 (where x2 = 0-0.5; y2 = -0.2-0.2, and z2 = -0.3-0.3) and 0-45 wt.% Nd-422 and 0-50 wt.% Sm-211; (a2) Sm-211, Nd-422, BaCuO2, and CuO; or (a3) Sm2O3, Nd2O3, BaO, BaCO3 and CuO; or (b) a mixture of (a2) and (a3); or (c) up to 12 wt.% in total of the following additives: 0-1.0 wt.% Pt, 0-2.0 wt.% Ce, 0.005-1.0 wt.% Rh, 0-2.0 wt.% Yb, and 0-6.0 wt.% Ag; and (d) up to a maximum 17 wt.% of the following: 0-2.0 wt.% BaO, 0-2.0 wt.% CaO, 0-2.0 wt.% MgO, 0-2.0 wt.% Al2O3, 0-2.0 wt.% BaZrO3, and 0-1.0 wt.% ZrO2, 0-1.0 wt.% V2O5, 0-1.0 wt.% TiO2, 0-1.0 wt.% Nb2O5, 0-1.0 wt.% Sb2O3, 0-1.0 wt.% BiO3; (B) mixing the powder in a ball mill, or asymmetric moved mixer; (C) molding the mixture using organic binder or auxiliary aid, or uniaxial and subsequent isostatic or isostatic or pressure-less molding and subsequent isostatic or casting, injection molding or extrusion process to form the green body; and (D) heat treating the green body.