Effect of mechanical deformation and annealing on the evolution of c-axis texture of Bi1.6Pb0.4Sr2Ca2Cu3O z superconductor hot-isostatic-press cladded onto a Ag substrate

A systematic study was undertaken of the mechanical deformation and annealing effects on the c-axis texture evolution of a Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O _z (BSCCO) superconductor cladded onto a Ag substrate. As the amount of cold-rolling reduction (%) increased, a tighter clustering of the (001 l4) poles around the surface normal indicated that randomly oriented grains from the initial hot-isostatic-press (HIP) cladded surface are progressively oriented nearly perpendicularly to the plane of the tape. Conventional X-ray diffraction (XRD), and X-ray pole-figure studies support a basal-plane sliding mechanism of plastic deformation. In samples annealed for 100 h, the superconductor (BSCCO) material near the BSCCO/Ag interface appears to undergo incipient melting, and there is a layer-like growth (c-axis texture), which extends macroscopically from the Ag interface. The sample-orientation distribution of short-term (5 h) annealed samples showed a strong c-axis texture, with the c-axis aligned nearly perpendicularly to the plane of the tape with no preferred alignment of the a- and b-axes.