Download - Fault Current Limiter
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Fault Current Limiter
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YBa2Cu3O7 Thin Film Fault current limiter
Qui ckTi me™ and aDV - PAL decompressor
are needed to see thi s pi cture.
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Bi 2212 Fault Current Limiter
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Bi2212 round wire vs Composite Reaction Texturing
(a)259-filamentary Bi2212 round wire (a) as drawn; (b) after heat treatment (c) EDAX atomic mapping of Bi (darker area) of a fragment of heat treated wire;
Source of distortion of the Bi2212 filaments: Retrograde densification and intergrowth
(b) (c)
MgO whiskersBi-2212
(a)
(b)
A schematic cross section of Bi2212/MgO-fibre composite (a) earlier stage of nucleation during cooling down and (b) final microstructure. MgO-fibre can be envisaged to align 2D random in plane.
An SEM micrograph of a thermally etched cross section of CRT coating showing also the gold contact interface. (An end view of the MgO-fibre shown represent the MgO-f plane).
50nm
7Þ
5Þ
6Þ3Þ
3Þ
3Þ
5Þ
1Þ
TEM of the melt textured Bi2212 (Composite Reaction Textured)
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Oxygen doping optimisation of Coated Bi2212 conductor
0
200
400
600
800
10-7 10-6 10-5 10-4 10-3 10-2 10-1 100
x=8.21, Tc=94Kx=8.22, Tc=90Kx=8.23, Tc=89Kx=8.24, Tc=82Kmelting
Co
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o C
pO2 (atm)
Bi-2212 melting
Bi-2212 unstable
(2) (1)
Schematic representation of the temperature and oxygen partial pressure dependence of the oxygen content, x, in Bi2Sr2CaCu2Ox phase; (1) sample slowly cooled under 0.21atm partial oxygen pressure, SC, and (2) sample SC(pO2).
High-resolution transmission electron microscopy (HRTEM) images of low angle grain boundaries recorded from individual grains of: (a) a slowly cooled conductor under constant oxygen partial pressure of 0.21 atm, SC; (b) conductor cooled under under monotonically reduced partial pressure of oxygen SC(pO2).
(a)(b)
0 100
5 103
1 104
1.5 104
2 104
2.5 104
65 70 75 80 85 90
SCSC(pO2)
Tran
sport
Jc A
cm
-2Temperature (K)
The temperature dependence of the transport Jc characteristics for tape SC(pO2) and SC.
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sT T
0 a log
10( pO
2)
To ensure that x=8.21 can be retain during the slow cooling procedure, the constant parameters of temperature, To and a, were chosen as To=870ºC and
a=60ºC.