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Imad Hamadneh 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.3
DyBa2Cu3O7-δ superconducting ceramic has been prepared from nano metal oxalate precursors with average grain size <30 nm using the coprecipitation method. Four sintering temperatures were applied for the same time period. XRD showed a single phase of an orthorhombic structure for all samples with small amount of 211 phase which was detected for samples sintered above 930°C. The sintered samples also exhibited metallic behaviour with TC(R=0) = 89 K - 90 K and the transport critical current density (JC) values enhanced from 4.35 A/cm2 to 12.9 A/cm2 as the sintering temperature increased. The SEM micrographs showed grains of large size that are randomly distributed and have irregular structure. The compaction between the grains was improved as sintering temperature increased and thus resulted in reducing the weak links effect. In conclusion, Reducing the gaps between the grain and the formation of 211 phase as pinning centers might be explain the enhancement in the transport current properties of Dy123 in a way to be used in the HTSC device applications.