Method of producing improved microstructure and properties for ceramic superconductors
Abstract
A ceramic superconductor is produced by close control of oxygen partial pressure during sintering of the material. The resulting microstructure of YBa.sub.2 Cu.sub.3 O.sub.x indicates that sintering kinetics are enhanced at reduced p(O.sub.2). The density of specimens sintered at 910.degree. C. increased from 79 to 94% theoretical when p(O.sub.2) was decreased from 0.1 to 0.0001 MPa. The increase in density with decrease in p(O.sub.2) derives from enhanced sintering kinetics, due to increased defect concentration and decreased activation energy of the rate-controlling species undergoing diffusion. Sintering at 910.degree. C. resulted in a fine-grain microstructure, with an average grain size of approximately 4 .mu.m. Such a microstructure results in reduced microcracking, strengths as high as 191 MPa and high critical current density capacity.
- Inventors:
-
- Naperville, IL
- Bloomington, IL
- Lombard, IL
- Glen Ellyn, IL
- Issue Date:
- Research Org.:
- Argonne National Laboratory (ANL), Argonne, IL (United States)
- OSTI Identifier:
- 870456
- Patent Number(s):
- 5525586
- Assignee:
- University of Chicago (Chicago, IL)
- DOE Contract Number:
- W-31109-ENG-38
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- method; producing; improved; microstructure; properties; ceramic; superconductors; superconductor; produced; close; control; oxygen; partial; pressure; sintering; material; resulting; yba; cu; indicates; kinetics; enhanced; reduced; density; specimens; sintered; 910; degree; increased; 79; 94; theoretical; decreased; 0001; mpa; increase; decrease; derives; due; defect; concentration; activation; energy; rate-controlling; species; undergoing; diffusion; resulted; fine-grain; average; grain; size; approximately; results; microcracking; strengths; 191; critical; current; capacity; ceramic superconductor; average grain; oxygen partial; current density; grain size; partial pressure; critical current; activation energy; close control; ceramic superconductors; resulting microstructure; producing improved; ceramic superco; /505/
Citation Formats
Singh, Jitendra P, Guttschow, Rob A, Dusek, Joseph T, and Poeppel, Roger B. Method of producing improved microstructure and properties for ceramic superconductors. United States: N. p., 1996.
Web.
Singh, Jitendra P, Guttschow, Rob A, Dusek, Joseph T, & Poeppel, Roger B. Method of producing improved microstructure and properties for ceramic superconductors. United States.
Singh, Jitendra P, Guttschow, Rob A, Dusek, Joseph T, and Poeppel, Roger B. Mon .
"Method of producing improved microstructure and properties for ceramic superconductors". United States. https://www.osti.gov/servlets/purl/870456.
@article{osti_870456,
title = {Method of producing improved microstructure and properties for ceramic superconductors},
author = {Singh, Jitendra P and Guttschow, Rob A and Dusek, Joseph T and Poeppel, Roger B},
abstractNote = {A ceramic superconductor is produced by close control of oxygen partial pressure during sintering of the material. The resulting microstructure of YBa.sub.2 Cu.sub.3 O.sub.x indicates that sintering kinetics are enhanced at reduced p(O.sub.2). The density of specimens sintered at 910.degree. C. increased from 79 to 94% theoretical when p(O.sub.2) was decreased from 0.1 to 0.0001 MPa. The increase in density with decrease in p(O.sub.2) derives from enhanced sintering kinetics, due to increased defect concentration and decreased activation energy of the rate-controlling species undergoing diffusion. Sintering at 910.degree. C. resulted in a fine-grain microstructure, with an average grain size of approximately 4 .mu.m. Such a microstructure results in reduced microcracking, strengths as high as 191 MPa and high critical current density capacity.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 1996},
month = {Mon Jan 01 00:00:00 EST 1996}
}