Stock material or miscellaneous articles – Web or sheet containing structurally defined element or... – Composite having voids in a component
Patent
1990-07-13
1991-10-15
van Balen, William J.
Stock material or miscellaneous articles
Web or sheet containing structurally defined element or...
Composite having voids in a component
4283128, 4283155, 4283157, 4283159, 428689, 428699, B32B 1800, B32B 518
Patent
active
050573624
ABSTRACT:
A unitary layered ceramic structure is disclosed which comprises co-sintered layers. The co-sintered structure comprises a sintered central layer of yttria stabilized zirconia ("YSZ") which is about 8 mole percent yttria and having a density of at least about 95% of theoretical, and sintered outer layers of strontium lanthanum manganite ("LSM") having the approximate molecular composition La.sub.0.8 Sr.sub.0.2 MnO.sub.3, having a density from about 50 to about 60% of theoretical, and having interconnected porosity from about 40 to 50% with an interconnected pore diameter from about one micron to about five microns. The sintered central layer is sandwiched by and bonded and sintered to the outer layers and is essentially free of significant amounts of manganese.
A process for making the unitary composition-of-matter is also disclosed which involves tape casting a LSM tape and then on top thereof casting a YSZ tape. The process comprises presintering LSM powder at 1250.degree. F., crushing the presintered commercially available LSM powder, forming a slurry with the crushed LSM, a binder and solvent, tape casting the slurry and allowing the slurry to air dry. A mixture of commercially available submicron size particle YSZ powder is milled with a dispersant and solvent to disperse the YSZ particles thereby forming a dispersed YSZ slurry. The YSZ slurry is then tape cast on the dried LSM tape. If desired, a third layer of LSM can be cast on top of the dried YSZ layer. After drying the composite LSM/YSZ and LSM/YSZ/LSM tapes are fired at 1300.degree. C. No migration of manganese into the YSZ layer was observed with scanning electron microscope/edax in the sintered multilayer tape.
REFERENCES:
patent: 1956607 (1934-05-01), Wyatt et al.
patent: 2582993 (1952-01-01), Howatt
patent: 3012086 (1957-07-01), Vahldieck
patent: 3143440 (1964-08-01), Hunger et al.
patent: 3441390 (1969-04-01), Backe et al.
patent: 3460991 (1969-08-01), White
patent: 3703413 (1972-11-01), Arrance
patent: 3793084 (1974-02-01), Marchetto
patent: 4007059 (1977-02-01), Witherspoon et al.
patent: 4064207 (1977-12-01), DeCrescente et al.
patent: 4091176 (1978-05-01), Alfenaar
patent: 4100331 (1978-07-01), Ingham et al.
patent: 4175153 (1979-11-01), Dobo et al.
patent: 4395468 (1983-07-01), Isenberg
patent: 4431715 (1984-02-01), Isenberg
patent: 4459341 (1984-07-01), Marchant et al.
patent: 4462891 (1984-07-01), Lawless
patent: 4490444 (1984-12-01), Isenberg
patent: 4506028 (1985-03-01), Fukuda et al.
patent: 4520082 (1985-05-01), Makiel
patent: 4554225 (1985-11-01), Sounai et al.
patent: 4587068 (1986-05-01), Borase et al.
patent: 4598028 (1986-07-01), Rossing et al.
patent: 4615717 (1986-10-01), Neubauer et al.
patent: 4698192 (1987-10-01), Kuze et al.
patent: 4740287 (1988-04-01), Cawfield
patent: 4756956 (1988-07-01), Nagai et al.
patent: 4783231 (1988-11-01), Raley
patent: 4798758 (1989-01-01), Nagano et al.
Schutz, Master Thesis; Title: A Preliminary Investigation of Radiation Catalysis in Fuel Cells; Aug. 1979, Virginia Polytechnic Institute and State University, Blacksburg, Va.; pp. 56 to 66 only.
Anderson Harlan U.
Schroeder James E.
California Institute of Technology
Logan F. Eugene
Van Balen William J.
LandOfFree
Multilayer ceramic oxide solid electrolyte for fuel cells and el does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multilayer ceramic oxide solid electrolyte for fuel cells and el, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multilayer ceramic oxide solid electrolyte for fuel cells and el will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-990038