Abstract
Silver addition has been known to improve mechanical and superconducting performance of bulk magnesium boride (MgB2) superconductor synthesized via solid state sintering. While formation of pinning phases and impurities such as Ag–Mg phases and MgO, respectively, responsible for high performance, part of the Mg in initial mixture will be expected to be consumed by silver. In this work, the authors add varied amounts of Mg systematically such as x: 2 (while x = 1.05, 1.075, 1.1, 1.125, 1.15) ratio of Mg:B instead of usual stoichiometric ratio of 1:2. To obtain high superconducting properties, the authors use carbon encapsulated boron (1.5% carbon) along with 4 wt% Ag. X-ray diffraction analysis shows the presence of Ag–Mg phases and minute amount of MgO. Superconducting quantum interference device (SQUID) measurements indicate that high irreversibility field (4.76 T) and large Jc of 520, 440, and 347 kA cm−2 at 10, 15, and 20 K, respectively, at self-field was exhibited in sample with x = 1.075. Flux pinning force studies are done to analyze the effect of secondary phases formed. All results analyzed explain the improved critical current performance based on nanometer-sized Ag–Mg particles in the final product.
| Original language | English |
|---|---|
| Article number | 1900497 |
| Journal | Advanced Engineering Materials |
| DOIs | |
| Publication status | Published - 2019 Jan 1 |
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Keywords
- Ag added bulk MgB
- carbon encapsulated boron
- excess Mg
- flux pinning
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
Cite this
Beneficial Impact of Excess Mg on Flux Pinning in Bulk MgB2 Synthesized with Ag Addition and Carbon Encapsulated Boron. / Arvapalli, Sai S.; Miryala, Muralidhar; Murakami, Masato.
In: Advanced Engineering Materials, 01.01.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Beneficial Impact of Excess Mg on Flux Pinning in Bulk MgB2 Synthesized with Ag Addition and Carbon Encapsulated Boron
AU - Arvapalli, Sai S.
AU - Miryala, Muralidhar
AU - Murakami, Masato
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Silver addition has been known to improve mechanical and superconducting performance of bulk magnesium boride (MgB2) superconductor synthesized via solid state sintering. While formation of pinning phases and impurities such as Ag–Mg phases and MgO, respectively, responsible for high performance, part of the Mg in initial mixture will be expected to be consumed by silver. In this work, the authors add varied amounts of Mg systematically such as x: 2 (while x = 1.05, 1.075, 1.1, 1.125, 1.15) ratio of Mg:B instead of usual stoichiometric ratio of 1:2. To obtain high superconducting properties, the authors use carbon encapsulated boron (1.5% carbon) along with 4 wt% Ag. X-ray diffraction analysis shows the presence of Ag–Mg phases and minute amount of MgO. Superconducting quantum interference device (SQUID) measurements indicate that high irreversibility field (4.76 T) and large Jc of 520, 440, and 347 kA cm−2 at 10, 15, and 20 K, respectively, at self-field was exhibited in sample with x = 1.075. Flux pinning force studies are done to analyze the effect of secondary phases formed. All results analyzed explain the improved critical current performance based on nanometer-sized Ag–Mg particles in the final product.
AB - Silver addition has been known to improve mechanical and superconducting performance of bulk magnesium boride (MgB2) superconductor synthesized via solid state sintering. While formation of pinning phases and impurities such as Ag–Mg phases and MgO, respectively, responsible for high performance, part of the Mg in initial mixture will be expected to be consumed by silver. In this work, the authors add varied amounts of Mg systematically such as x: 2 (while x = 1.05, 1.075, 1.1, 1.125, 1.15) ratio of Mg:B instead of usual stoichiometric ratio of 1:2. To obtain high superconducting properties, the authors use carbon encapsulated boron (1.5% carbon) along with 4 wt% Ag. X-ray diffraction analysis shows the presence of Ag–Mg phases and minute amount of MgO. Superconducting quantum interference device (SQUID) measurements indicate that high irreversibility field (4.76 T) and large Jc of 520, 440, and 347 kA cm−2 at 10, 15, and 20 K, respectively, at self-field was exhibited in sample with x = 1.075. Flux pinning force studies are done to analyze the effect of secondary phases formed. All results analyzed explain the improved critical current performance based on nanometer-sized Ag–Mg particles in the final product.
KW - Ag added bulk MgB
KW - carbon encapsulated boron
KW - excess Mg
KW - flux pinning
UR - http://www.scopus.com/inward/record.url?scp=85067868150&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85067868150&partnerID=8YFLogxK
U2 - 10.1002/adem.201900497
DO - 10.1002/adem.201900497
M3 - Article
JO - Advanced Engineering Materials
JF - Advanced Engineering Materials
SN - 1438-1656
M1 - 1900497
ER -