Confinement of self-generated Mg(BH4)2 particles for simultaneously enhanced flux pinning and grain connectivity in polycrystalline H-doped MgB2

Ganggang Cui; Qi Cai; Yanmo Li; Qilin Yu

doi:10.1088/1361-6668/acb2fb

Confinement of self-generated Mg(BH₄)₂ particles for simultaneously enhanced flux pinning and grain connectivity in polycrystalline H-doped MgB₂

Ganggang Cui, Qi Cai^*, Yanmo Li, Qilin Yu

^*Corresponding author for this work

School of Material Science and Engineering

Research output: Contribution to journal › Article › peer-review

2 Citations (Scopus)

Abstract

The present study reports a simple quenching method to simultaneously improve flux pinning and grain connectivity in polycrystalline H-doped MgB₂, which was ex-situ synthesized at 350 °C under the H₂ pressure of 3 MPa. Quenching prevented the phase transformation of β-Mg(BH₄)₂→α-Mg(BH₄)₂ upon cooling, and the dominant point-pinning effects originated from the self-generated nano-sized β-Mg(BH₄)₂ particles that were confined within the MgB₂ grains. A semi-coherent relationship was found between MgB₂(100) and Mg(BH₄)₂( 1 ˉ 1 4 ˉ ) planes. Meanwhile, the precipitation-induced expansion of the MgB₂ grains remained at room temperature, leading to an increasing number of contact points as well as grain connectivity. Compared with the un-doped MgB₂, the quenched H-doped one exhibited enhanced critical current density over the entire field. These results are expected to guide the design of flux pinning centers for improving the J _c performance of standard type II superconductors.

Original language	English
Article number	035002
Journal	Superconductor Science and Technology
Volume	36
Issue number	3
DOIs	https://doi.org/10.1088/1361-6668/acb2fb
Publication status	Published - Mar 2023

Keywords

H doping
MgB superconductors
critical current density
grain connectivity
quenching

Access to Document

10.1088/1361-6668/acb2fb

Cite this

@article{c5245fb6964c422ebb2b3d0aa338693c,

title = "Confinement of self-generated Mg(BH4)2 particles for simultaneously enhanced flux pinning and grain connectivity in polycrystalline H-doped MgB2",

abstract = "The present study reports a simple quenching method to simultaneously improve flux pinning and grain connectivity in polycrystalline H-doped MgB2, which was ex-situ synthesized at 350 °C under the H2 pressure of 3 MPa. Quenching prevented the phase transformation of β-Mg(BH4)2→α-Mg(BH4)2 upon cooling, and the dominant point-pinning effects originated from the self-generated nano-sized β-Mg(BH4)2 particles that were confined within the MgB2 grains. A semi-coherent relationship was found between MgB2(100) and Mg(BH4)2( 1 ˉ 1 4 ˉ ) planes. Meanwhile, the precipitation-induced expansion of the MgB2 grains remained at room temperature, leading to an increasing number of contact points as well as grain connectivity. Compared with the un-doped MgB2, the quenched H-doped one exhibited enhanced critical current density over the entire field. These results are expected to guide the design of flux pinning centers for improving the J c performance of standard type II superconductors.",

keywords = "H doping, MgB superconductors, critical current density, grain connectivity, quenching",

author = "Ganggang Cui and Qi Cai and Yanmo Li and Qilin Yu",

note = "Publisher Copyright: {\textcopyright} 2023 IOP Publishing Ltd.",

year = "2023",

month = mar,

doi = "10.1088/1361-6668/acb2fb",

language = "English",

volume = "36",

journal = "Superconductor Science and Technology",

issn = "0953-2048",

publisher = "IOP Publishing Ltd.",

number = "3",

}

TY - JOUR

T1 - Confinement of self-generated Mg(BH4)2 particles for simultaneously enhanced flux pinning and grain connectivity in polycrystalline H-doped MgB2

AU - Cui, Ganggang

AU - Cai, Qi

AU - Li, Yanmo

AU - Yu, Qilin

PY - 2023/3

Y1 - 2023/3

N2 - The present study reports a simple quenching method to simultaneously improve flux pinning and grain connectivity in polycrystalline H-doped MgB2, which was ex-situ synthesized at 350 °C under the H2 pressure of 3 MPa. Quenching prevented the phase transformation of β-Mg(BH4)2→α-Mg(BH4)2 upon cooling, and the dominant point-pinning effects originated from the self-generated nano-sized β-Mg(BH4)2 particles that were confined within the MgB2 grains. A semi-coherent relationship was found between MgB2(100) and Mg(BH4)2( 1 ˉ 1 4 ˉ ) planes. Meanwhile, the precipitation-induced expansion of the MgB2 grains remained at room temperature, leading to an increasing number of contact points as well as grain connectivity. Compared with the un-doped MgB2, the quenched H-doped one exhibited enhanced critical current density over the entire field. These results are expected to guide the design of flux pinning centers for improving the J c performance of standard type II superconductors.

AB - The present study reports a simple quenching method to simultaneously improve flux pinning and grain connectivity in polycrystalline H-doped MgB2, which was ex-situ synthesized at 350 °C under the H2 pressure of 3 MPa. Quenching prevented the phase transformation of β-Mg(BH4)2→α-Mg(BH4)2 upon cooling, and the dominant point-pinning effects originated from the self-generated nano-sized β-Mg(BH4)2 particles that were confined within the MgB2 grains. A semi-coherent relationship was found between MgB2(100) and Mg(BH4)2( 1 ˉ 1 4 ˉ ) planes. Meanwhile, the precipitation-induced expansion of the MgB2 grains remained at room temperature, leading to an increasing number of contact points as well as grain connectivity. Compared with the un-doped MgB2, the quenched H-doped one exhibited enhanced critical current density over the entire field. These results are expected to guide the design of flux pinning centers for improving the J c performance of standard type II superconductors.

KW - H doping

KW - MgB superconductors

KW - critical current density

KW - grain connectivity

KW - quenching

UR - http://www.scopus.com/inward/record.url?scp=85146830574&partnerID=8YFLogxK

U2 - 10.1088/1361-6668/acb2fb

DO - 10.1088/1361-6668/acb2fb

M3 - Article

AN - SCOPUS:85146830574

SN - 0953-2048

VL - 36

JO - Superconductor Science and Technology

JF - Superconductor Science and Technology

IS - 3

M1 - 035002

ER -

Confinement of self-generated Mg(BH₄)₂ particles for simultaneously enhanced flux pinning and grain connectivity in polycrystalline H-doped MgB₂

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this