The Boeing Company

The Washington Technology Center

Corrie B Martin

Kay Youngdahl Blohowiak

Michael Strasik

Darryl F Garrigus

Kevin Earl McCrary

Thomas S Luhman

Gary D Maupin

Ilhan A Aksay

Randal P Kurosky

Fatih Dogan

Ilhan Aksay

William C Hicks

Chan Han

Gregory C Stangle

We make large (in excess of 2 cm in diameter), single crystal YBa.sub.2 Cu.sub.3 O.sub.7-x [123 YBCO] crystals, where x.ltoreq.0.6, in a seventeen step process or some variant thereof from finely ground and well mixed 123 YBCO and 211 YBCO powders with a small amount of Pt by controlling the rate of cooling from within a compact of the powders using a temperature gradient in the radial and axial planes (independently) of about 1-1.degree. C./inch diameter of compact to nucleate the crystal growth. We promote crystal growth as well using a samarium oxide seed crystal, preferably SmBa.sub.2 Cu.sub.3 O.sub.(7-y), where y.ltoreq.1.6. After nucleation we cool the compact slowly at a rate from about 0.1-1.degree. C./hr to promote the single crystal development.

Making large, single crystal, 123 YBCO superconductors

Ceramic precursor mixtures containing a metal cation, a carbohydrate, and an anion capable of participating in an anionic oxidation-reduction reaction with the carbohydrate for continuous or batchwise drying and pyrolyzing to provide ceramic powders.

Ceramic precursor mixture and technique for converting the same to

Growing community of inventors

Seattle, WA, United States of America

Corrie B Martin