Rapid Formation of the High T sub c Phase in the Bi--Pb--Sr--Ca--Cu--O System Using Powders Prepared by Emulsion Drying Method

The superconducting powders in the Bi--Pb--Sr--Ca--Cu--O system were easily prepared from water in oil type emulsion by loading the bismuth, Pb, Sr, Ca and Cu ions into the aqueous phase. The low T sub c phase (Bi(Pb) sub 2 Sr sub 2 Ca sub 1 Cu sub 2 O sub y ) was formed by calcining at 800 deg C fo...

Full description

Saved in:
Bibliographic Details
Published in:Solid state communications 1990-08, Vol.75 (5), p.455-458
Main Authors: Um, W S, Kim, H G
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The superconducting powders in the Bi--Pb--Sr--Ca--Cu--O system were easily prepared from water in oil type emulsion by loading the bismuth, Pb, Sr, Ca and Cu ions into the aqueous phase. The low T sub c phase (Bi(Pb) sub 2 Sr sub 2 Ca sub 1 Cu sub 2 O sub y ) was formed by calcining at 800 deg C for 10 h in a low oxygen partial pressure of 1/20 atm. The shape of the calcined powder is thin plate of size approx 2 mu m and thickness < 0.5 mu m. It was observed that the high T sub c phase (Bi(Pb) sub 2 Sr sub 2 Ca sub 2 Cu sub 3 O sub y ) was formed by sintering at 850 deg C for 30 h in O pressure of 1/20 atm without intermediary grinding. The above sintered sample exhibited superconductivity with a T sub c (zero) = 105K. 12 ref.--AA
ISSN:0038-1098