Influence of pelletization pressure on magnetic susceptibility samples of ceramics Bi (Pb)–Sr–Ca–Cu–O

• Published in: Physica. C, Superconductivity Superconductivity, 1999, Vol.311 (1), p.81-85
• Main Authors: Fradina, I.A., Alekseev, A.F., Gridasova, T.Ja, Morozov, V.V., Jurchenko, D.O.
• Format: Article
• Language: English
• Subjects: Grain boundaries; Magnetic susceptibility; Scanning electron microscopy
• ISSN: 0921-4534; 1873-2143
• DOI: 10.1016/S0921-4534(98)00563-2

The influence of pelletization pressing 100–500 MPa on the quality of the samples from Bi 1.7Pb 0.3Sr 2Ca 2.5Cu 3.5O 10+ δ superconducting transition was investigated. Samples which were pelletized at 100, 200, 300 MPa increased weight by an uncontrollable diffusion of elements from a filling. Obviously, these elements form additive phases on borders of grains, what is possible to conclude from the dependence χ′– T. The weight of samples pressed at pressure 400 and 500 MPa practically does not change at sintering. These samples after sintering within 250 h have a rather precise superconducting transition from a magnetic susceptibility. XRD shows that the phase structure of samples differs insignificantly—after sintering time 250 h samples consist basically of a phase 2223. The powder of the same composition annealed also within 250 h without a filling by results of XRD consists of approximately equal amounts of phases 2223 and 2212.