Abstract: A process which relies on a joining technique between two individual strongly linked superconductors is disclosed. Specifically, this invention relates to fabrication of single domains of YBa2Cu3Ox or YBa2Cu3Ox with the addition of Y2BaCuO5 and/or other secondary phases such as Pt/PtO2, CeO2, SnO2, Ag, Y2O3 and other rare earth oxides, by using a top-seeded, melt processing technique. Beginning with a single crystal seed such as Nd1+xBa2−xCu3Ox or SmBa2Cu3Ox crystals, a melt-textured YBCO domain with crystallographic orientation nearly similar to that of the seed crystal can be fabricated. The samples are next machined to desired geometrical shapes. A bonding material is then applied to the ac plane. Low solidification or recrystalization point, similar crystal structure to that of YBa2Cu3Ox, and capability of growing epitaxially on YBCO domains are critical parameters of the bonding material.

Abstract: A process which relies on a joining technique between two individual strongly linked superconductors is disclosed. Specifically, this invention relates to fabrication of single domains of YBa2Cu3Ox or YBa2Cu3Ox with the addition of Y2BaCuO5 and/or other secondary phases such as Pt/PtO2, CeO2, SnO2, Ag, Y2O3 and other rare earth oxides, by using a top-seeded, melt processing technique. Beginning with a single crystal seed such as Nd1+xBa2−xCu3O3 or SmBa2Cu3Ox crystals, a melt-textured YBCO domain with crystallographic orientation nearly similar to that of the seed crystal can be fabricated. The samples are next machined to desired geometrical shapes. A bonding material is then applied to the ac plane. Low solidification or recrystalization point, similar crystal structure to that of YBa2Cu3Ox, and capability of growing epitaxially on YBCO domains are critical parameters of the bonding material.

Abstract: In accordance with the invention a process is provided for achieving a phase-pure BSCCO or lead doped BSCCO powder or precursor of the 2201, 2212 or 2223 phase. In this process a cation solution is intimately mixed with an anion solution and precipitation is caused at a carefully controlled pH in the range from about 10 to about 12.5. The resulting product is filtered and dried or heat-treated at a temperature of from about 400.degree. to about 500.degree. C. for a period of from about 8 to about 12 hours. The heat-treated powder is then subjected to a second heat treatment at a reduced oxygen of from about 3 to about 10 torr and a temperature of from about 700.degree. to about 800.degree. to form a precursor powder. The precursor powder is heat-treated at ambient pressure in CO.sub.2 -free air from about 12 to about 31 hours or more at a temperature of from about 800.degree. to about 850.degree. C.