|
|
Details
Back to List
From imperfect to perfect Bi2Sr2CaCu2Ox (Bi-2212) grains
Author |
|
Heeb, B.; Gauckler, L.J.; Heinrich, H.; Kostorz, G. |
Year |
|
1993 |
Type
|
|
Journal Article |
Journal |
|
J. Mater. Res. |
Volume |
|
8 |
Issue |
|
9 |
Pages |
|
2170-2176 |
Date |
|
1993/9 |
Custom 1 |
|
JA |
Custom 2 |
|
SUPRA |
Abstract |
|
The 2212 phase formation during annealing of melt textured Bi-2212 (Bi2Sr2CaCu2Ox) was investigated using differential thermal analysis, thermal gravimetric analysis, x-ray diffraction, scanning electron microscopy, energy dispersive x-ray analysis, and high resolution transmission electron microscopy. After zone melting, the material is multiphase consisting of 2212, 2201, Sr1-x CaxCuO2, and the eutectic. The 2212 phase formed is highly perfect with less than 5% intergrowths of 2201 layers; the 2201 phase shows no intergrowth of 2212 at all. In the first period of the annealing, remelting of the eutectic leads to fast oxygen diffusion and a high 2212 formation rate. The 2201 [Arrow Right] 2212 transformation proceeds via intermediate states of high defect density. The 2212 grains contain up to 30-70% 2201 intergrowths. Further heat treatments lead to an annihilation of the great majority of intergrown 2201 layers. We propose a model for the formation of 2212 grains with a low planar defect density, based on frequent stacking faults, that allows diffusion of Ca-and Cu-atoms over a short distance. The model provides a schematic description of this solid-state process and correlates it to the characteristic microstructural features of melt-processed Bi-2212. [Author abstract; 17 Refs; In English] |
URL |
|
|
Record Number |
|
109 |
Group
|
|
nonmet |
Back to List
Wichtiger Hinweis:
Diese Website wird in älteren Versionen von Netscape ohne
graphische Elemente dargestellt. Die Funktionalität der
Website ist aber trotzdem gewährleistet. Wenn Sie diese
Website regelmässig benutzen, empfehlen wir Ihnen, auf
Ihrem Computer einen aktuellen Browser zu installieren. Weitere
Informationen finden Sie auf
folgender
Seite.
Important Note:
The content in this site is accessible to any browser or
Internet device, however, some graphics will display correctly
only in the newer versions of Netscape. To get the most out of
our site we suggest you upgrade to a newer browser.
More
information