Excellent Critical Current Properties of Dilute Sr-Doped Dy123 Melt-Solidified Bulks at Low Temperatures

We have previously reported that dilute impurity doping technique universally enhances the critical current density of RE123 superconductors. These doping effects on the
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properties depend on substituted cation sites. In this paper, we report the flux pinning properties of the dilute Sr- or Co-doped Dy123 melt-solidified bulks in a wide temperature range. It was found that the dilute Sr-doping effectively enhance the
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for Dy123 melt-solidified bulks with low level Dy/Ba substitution. For the dilute Sr-doped Dy123 samples, the temperature coefficient of
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in 30 kOe was found to be approximately two times larger than for undoped materials above 40 K, meaning that it is an effective method for developing high-
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RE123 materials operating at low temperatures.