Effect of Na and Ag co-doping on the electrical and mechanical properties of Bi-2212 textured materials

Abstract

Bi2Sr2Ca1.95Na0.05Cu2Oy + x wt.% Ag materials with x=0, 1, 3, and 5, were prepared by a sol-gel via nitrates method followed by a texturing process by the laser floating zone technique described in detail elsewhere. As it is well known, Na allows raising magnetic properties when it is added in the adequate proportions. Moreover, metallic Ag additions have been shown very advantageous from the point of view of the mechanical and electrical properties. This effect is due to the improvement of the grain boundaries reinforcing, at the same time, the bulk material as Ag is found filling the holes between superconducting grains. As a consequence, the effect of simultaneous addition of the optimum Na amount with different metallic Ag contents will be studied in this work. It has been found that microstructure is directly affected by the Ag amount, and these modifications in microstructure are reflected in changes in the electrical (JC and TC), and mechanical properties (by three point bending).