Influence of amorphous boron grain size, high ısostatic pressure, annealing temperature, and filling density of unreacted material on structure, critical parameters, n-value, and engineering critical current density in MgB2 wires
Yükleniyor...
Dosyalar
Tarih
2021
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
MDPI
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Our results show that a lower density of unreacted Mg + B material during an Mg solid-state synthesis reaction leads to a significant reduction in the quantity of the superconducting phase and lowers the homogeneity of the superconducting material. It also significantly reduces the irreversible magnetic field (B-irr), critical temperature (T-c), upper magnetic field (B-c2), engineered critical current density (J(ec)), and n-value, despite high isostatic pressure (HIP) treatment and the use of nanoboron in the sample. Our measurements show that samples with large boron grains with an 8% higher density of unreacted Mg + B material allow better critical parameters to be achieved. Studies have shown that the density of unreacted material has little effect on B-irr, T-c, B-c2, J(ec), and the n-value for an Mg liquid-state synthesis reaction. The results show that the critical parameters during an Mg liquid-state synthesis reaction depend mainly on grain size. Nanoboron grains allow for the highest B-irr, T-c, B-c2, J(ec), and n-values. Scanning electron microscopy (SEM) images taken from the longitudinal sections of the wires show that the samples annealed under low isostatic pressure have a highly heterogeneous structure. High isostatic pressure heat treatment greatly improves the homogeneity of MgB2.
Açıklama
This research was funded by the Institute of Low Temperature and Structure Research, PAS, the Institute of High Pressure Physics, PAS and Ministry of National Defense Republic of Poland Program-Research Grant MUT Project 13-995. The wire samples of this work were fabricated with financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) research project with grant numbers 217 M665.
Anahtar Kelimeler
Mgb2 Superconducting Wires, Boron Grain Size, Density of Unreacted Material, High Isostatic Pressure, Critical Current Density
Kaynak
Materials
WoS Q Değeri
Q1
Scopus Q Değeri
Q2
Cilt
14
Sayı
13
Künye
Gajda, D., Zaleski, A. J., Morawski, A., Małecka, M., Akdoğan, M., Karaboğa, F., ... & Czujko, T. (2021). Influence of amorphous boron grain size, high isostatic pressure, annealing temperature, and filling density of unreacted material on structure, critical parameters, n-value, and engineering critical current density in MgB2 wires. Materials, 14(13), 3600.
