Superconductor technology: apparatus – material – process – High temperature – per se – Having tc greater than or equal to 150 k
Patent
1988-12-09
1992-06-16
Lieberman, Paul
Superconductor technology: apparatus, material, process
High temperature , per se
Having tc greater than or equal to 150 k
423493, 423604, 423635, 501123, 505737, 505738, C01B 1336, C01F 1102, C01F 1700, C01G 302
Patent
active
051225085
ABSTRACT:
A process for preparing a bulk powder for an oxide superconductor which comprises mixing an alcohol solution (I) of a copper nitrate and a lanthanoid metal nitrate with an alcohol solution (II) comprising at least one compound selected from the group consisting of a barium hydroxide and a barium alkoxide to give a coprecipitate, and thermally decomposing the coprecipitate. According to the present invention, compared to the solid-state reaction, fine particles having the particle size of not more than 1 .mu.m can be easily produced because barium carbonate comparatively stable to heat is not formed on calcination, and the desired bulk powder for oxide superconductor can be produced at even lower temperature. Consequently, the obtained bulk powder for the oxide superconductor has fine particles, e.g. the particle size being not more than 1 .mu.m, therefore, the powder is excellent in stoichinometry, large in surface energy and excellent in sintering property.
REFERENCES:
patent: 4636378 (1987-01-01), Pastor et al.
patent: 4643984 (1987-02-01), Abe et al.
patent: 4661287 (1987-04-01), Clark
patent: 4696810 (1987-09-01), Shirasaki et al.
patent: 4764357 (1988-08-01), Sherif et al.
patent: 4845056 (1989-07-01), Yamanis
patent: 5019555 (1991-05-01), Chin et al.
Wang et al., Inorg. Chem., 26, 1474 (1987).
Inoue et al., Jpn. J. Applied Physics, 26, L 1443 (1987).
Fujiki, M. et al, "Preparation of a High-T.sub.c Y--Ba--Cu--O Superconductor Using Colloidal Methods", Japanese Journal of Applied Physics, vol. 26, No. 7, Jul. 1987, pp. L1159-L1160.
Kaneko, K., et al, "On the Coprecipitation Method for the Preparation of High T.sub.c M--X--Cu--O (M.dbd.Ba, Sr, X.dbd.La, Y) System", Japanese Journal of Applied Physics, vol. 26, No. 5, May, 1987, pp. L734-L735.
Nakahara "On the defect structure of Grain Boundaries in . . . " Mat. Res. Soc. Symp. Proc. vol. 99 Dec. 4, 1987, pp. 575-578.
Bordia "Sintering and Microstructure--Property Relations for . . . " Mat. Res. Soc. Symp. Proc. vol. 99, Dec. 4, 1987 pp. 245-248.
Viegers "Oxygen Content, Microstructure and Superconductivity of . . . " J. Mater. Res. 2(6) Nov./Dec. 1987 pp. 743-749.
Pfalzgraf "Alkoxides as Molecular Precursors for Oxide-based . . . " New Jnl. of Chem. vol. 11 No. 10 1987 pp. 663-675.
Tarascon "High-Temp. Supercond. Oxide Symthesis and the . . . " ACS Symp.: Chem. of High-T. Sup. vol. 351 Sep. 1987 pp. 148-209.
R. S. Lin "Application of Gel Technology in Preparation of High--Tc . . . " Mat. Res. Soc. Symp. Proc. vol. 99 Dec. 1987 pp. 253-256.
Vilminot "Symthesis and Characterization of YBa.sub.2 Cu.sub.3 O.sub.7-x Supercond . . . " Mat. Res. Bull. vol. 23 1988 pp. 521-529.
Amarakoon "Synthesis, Characterization and Fabrication of High T . . . " Ad. Cer. Matls. vol. 2, No. 3B Special Issue Jul. 1987 pp. 539-555.
Kawa "Preparation of High-Tc Y--Ba--Cu--O Superconductor" Jap. Jnl. Appl. Phys. vol. 26(5) May 1987 pp. L736-737.
Hirabayashi "Structure and Superconductivity in a New Type of . . . " Jap. Jnl. Appl. Phys. vol. 26(4) Apr. 1987 pp. L454-455.
Manthiram "Synthesis of the High--Tc Superconductor YBa.sub.2 Cu.sub.3 O.sub.x . . . " Nature vol. 329 Oct. 22, 1987 pp. 701-702.
Grant T Hackh's Chemical Dictionary 5th Ed. McGraw-Hill Bank Company: 1987 p. 470.
Nanao Tsutomu
Yamamoto Kenji
Yokoyama Masao
Boya John
Kanegafuchi Kagaku Kogyo & Kabushiki Kaisha
Lieberman Paul
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