Microstructural and electrical transport properties of uniaxially pressed ceramic superconductors

Abstract: We have studied the effect of the pelletization pressure on microstructural and electrical transport properties of superconducting ceramics with starting composition given by the formula . The experimental data of electrical measurements was processed in order to obtain the weak-link resistivity, the orientation probability of the grains’ a-axes along a certain preferential direction, the slope of the linear part in the temperature dependence of the ab-planes resistivity, and the intrinsic effective anisotropy of the grains, of each sample. In contrast with the behaviour of ceramics, the Ca, Cu enriched samples exhibit a reduction of their effective anisotropy at sample level and weak links resistivity with increasing compacting pressures. In addition, a compacting pressure of around 488 MPa may affect considerably the electrical and structural parameters of the material. The results suggest that a combined effect of the pelletization pressure and the doping with Ca and Cu can be used to improve the electrical transport properties of these materials for technological applications.

Author(s): Cruz-Garcia, A; Fernandez-Gamboa, JR; Altshuler, E; Jardim, RF; Vazquez-Robaina, O; Mune, P

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS

DOI: 10.1007/s10854-018-8594-2