IS Y2BaCuO5 INCLUSION EFFECTIVE PINNING SITE IN YBa2Cu3O7?

Murakami, Masato; Fujimoto, Hiroyuki; Yamaguchi, Keita; Nakamura, N.; Koshizuka, N.; Tanaka, Shōji

doi:10.2978/jsas.4.75

Cited by 7 publications

(5 citation statements)

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“…The fundamental criterion in achieving high J c in REBCO superconducting materials is engineering of the bulk matrix with fine-sized non-superconducting inclusions. It was predicted that the effective surface area of these particles is proportional to the flux pinning of the bulk samples . Among, non-superconducting and non-interacting inclusions such as the 211 phase, particles are considered as effective pinning centers.…”

Section: Resultsmentioning

confidence: 99%

Production of Sharp-Edged and Surface-Damaged Y₂BaCuO₅ by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa₂Cu₃O_7−δ Bulk Superconductors

et al. 2020

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Growth and physical properties of bulk REBa2Cu3O7−δ (REBCO) superconductors fabricated by the infiltration growth (IG) method strongly depend on the initial size and morphology of the RE2BaCuO5 (211) particles. The present work details the novel method we developed for producing sharp-edged and surface-damaged 211 particles to be added to the REBCO bulks. We employed high-energy ultrasonic irradiation for pretreating the 211 particles and fabricated high-performance bulk single-grain YBa2Cu3O7−δ (YBCO) superconductors via the top-seeded IG process. Increasing the ultrasound irradiation power and time duration mechanically damaged the surface of the 211 particles, producing more fine and sharp edges. Systematic investigations of the microstructural properties of the final YBCO bulks indicated that the size and content of the 211 particles gradually decreased without any additional chemical doping. The effective grain refinement and improved interfacial defect densities enhanced the critical current density by a factor of two at 77 K and self-field as compared to a YBCO sample fabricated without any pretreatment. A maximum trapped field of 0.48 T at 77 K was obtained for a sample (20 mm diameter) with 211 particles treated for 60 min and 300 W ultrasound radiation. The effectiveness of the novel method is demonstrated by the superior performance of the YBCO bulk samples prepared as compared to bulk samples fabricated with the addition of Pt and CeO2. This method is novel, cost effective, and very convenient, maintaining high sample homogeneity, and is free of chemical contaminants as compared to other methods which significantly affect the properties of all REBCO bulk products grown by sintering, melt growth, and IG methods.

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Section: Resultsmentioning

confidence: 99%

Production of Sharp-Edged and Surface-Damaged Y₂BaCuO₅ by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa₂Cu₃O_7−δ Bulk Superconductors

et al. 2020

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“…In the case of 211 particles in Y-123 superconductor, the proportionality given by equation ( 5) was confirmed by Murakami et al [3]. It was also shown that the temperature and field dependencies given by equation (7) were satisfied [2].…”

Section: Pinning By Nonsuperconducting Particlesmentioning

confidence: 66%

Flux pinning in superconducting 123 materials

Matsushita

2000

Supercond. Sci. Technol.

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Mechanisms, features, and properties of strong flux pinning in superconducting 123 materials are reviewed. These include pinning by nonsuperconducting particles of 211 or 422 phase, regions with lower critical temperature (T c ) such as a region where Ba sites are substituted for with light rare-earth elements and an oxygen-deficient region, and radiation-induced columnar defects. In particular, the pinning by lower-T c regions which seem to be associated with the well-known pronounced peak effect are focused upon. It is speculated that these regions work as strong repulsive pinning centres resulting from the kinetic energy of the order parameter under a significant proximity effect. This pinning mechanism is different from the usual attractive condensation energy interaction which occurs in 211 or 422 particles. A discussion will be given on the mechanism which brings about the peak effect. General guiding principles for the improvement of the flux pinning property will also be discussed.

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“…the formation of a microstructure with fine-sized, non-superconducting inclusions, is crucial. As predicted, the flux pinning of the bulk samples is proportional to the effective surface area of these non-superconducting phases [50]. Among them, crystalline defects generated due to the RE211/RE123 interfaces (δl pinning) effectively pins the fluxons and improves the J c performance of these products [51][52][53][54].…”

Section: Microstructural Propertiesmentioning

confidence: 74%

Investigation of high-energy ultrasonication of RE₂BaCuO₅(RE = Y, Gd) on the growth and superconducting properties of REBa₂Cu₃O_7−δtop-seeded melt textured bulks

Naik¹,

Hagiwara²,

Ishibashi³

et al. 2022

Supercond. Sci. Technol.

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Recently, the improvement of flux pinning performance of REBa2Cu3O7-δ (REBCO) bulk was achieved employing high energy ultrasonic irradiation (up to 300 W and 60 min) prior to the infiltration-growth process. Here, we demonstrate that higher ultrasonic power and shorter duration treatment (450 W for 30 min) of the RE2BaCuO5 (RE211, RE = Y, Gd) powder produces individual, nanometer-sized and surface damaged ultrasonically pre-treated RE211 particles (RE211Ultra). We study the growth of YBCO and GdBCO systems via top-seeded melt-growth (TSMG) method and with the addition of 30 mol% of RE211Ultra, which were pre-treated by high-energy ultrasonication and compared with the conventional method. Isothermal growth experiments clarified that the addition of RE211Ultra particles enables faster and more effective crystal growth via an improved peritectic reaction due to their size in the nanometer range and due to the presences of sharp edges, which is crucial for growing large, single grain bulks of REBCO. Microstructural investigations by scanning electron microscopy indicated the presence of 2 differently sized RE211 inclusions within the bulk GdBCO and YBCO superconductors. All samples showed an onset of superconductivity at ~92 K or above. Utilizing the effective growth temperature window and the addition of RE211Ultra, single grain bulks of GdBCO and YBCO were fabricated by the slow-cooling method. The field dependence critical current density (Jc) of the bulk samples using RE211Ultra were found to exhibit superior performance over the standard GdBCO/ YBCO samples due to significant changes of sample growth and of their microstructures. Here, we discuss various factors affecting the addition of RE211Ultra on the development of the microstructure, the growth of bulk, single grain materials and further, the superconducting properties of different REBCO superconductors.

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IS Y2BaCuO5 INCLUSION EFFECTIVE PINNING SITE IN YBa2Cu3O7?

Cited by 7 publications

References 1 publication

Production of Sharp-Edged and Surface-Damaged Y₂BaCuO₅ by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa₂Cu₃O_7−δ Bulk Superconductors

Production of Sharp-Edged and Surface-Damaged Y₂BaCuO₅ by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa₂Cu₃O_7−δ Bulk Superconductors

Flux pinning in superconducting 123 materials

Investigation of high-energy ultrasonication of RE₂BaCuO₅(RE = Y, Gd) on the growth and superconducting properties of REBa₂Cu₃O_7−δtop-seeded melt textured bulks

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IS Y2BaCuO5 INCLUSION EFFECTIVE PINNING SITE IN YBa2Cu3O7?

Cited by 7 publications

References 1 publication

Production of Sharp-Edged and Surface-Damaged Y2BaCuO5 by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa2Cu3O7−δ Bulk Superconductors

Production of Sharp-Edged and Surface-Damaged Y2BaCuO5 by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa2Cu3O7−δ Bulk Superconductors

Flux pinning in superconducting 123 materials

Investigation of high-energy ultrasonication of RE2BaCuO5(RE = Y, Gd) on the growth and superconducting properties of REBa2Cu3O7−δtop-seeded melt textured bulks

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Product

Resources

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Production of Sharp-Edged and Surface-Damaged Y₂BaCuO₅ by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa₂Cu₃O_7−δ Bulk Superconductors

Production of Sharp-Edged and Surface-Damaged Y₂BaCuO₅ by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa₂Cu₃O_7−δ Bulk Superconductors

Investigation of high-energy ultrasonication of RE₂BaCuO₅(RE = Y, Gd) on the growth and superconducting properties of REBa₂Cu₃O_7−δtop-seeded melt textured bulks