Abstract: A method of producing a superconductor of metal oxides which includes subjecting an organic solvent solution containing (a) an alkoxide of a rare earth element, (b) an alkoxide of an alkaline earth metal and (c) copper alkoxide or cupric nitrate to hydrolysis in the presence of water and nitrate ions, thereby forming a mixture containing a gel-like substance. The gel-like substance is, after being dried and formed into a desired shape, pyrolyzed at a temperature of 600.degree.-950.degree.C. to form a superconductor of oxides of the rare earth, the alkaline earth metal and copper.

Abstract: A process for forming a thin oxide film on an underlying surface adapted for film formation thereon according to a radio frequency magnetron sputtering method using an oxide target(s). The excitation frequency is a frequency which is higher than 13.56 MHz and which provides a negative target self-bias voltage permitting of film formation.

Abstract: The present invention provides an oxide superconductor which has a relatively high transition temperature T.sub.c. This superconductor has the chemical formula (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.3 O.sub.7-z wherein R is at least one rare earth element selected from the group consisting of Tm, Yb and Lu, x is with in the range of 0.1.ltoreq..times.0.5, y is within the range of 0.1.ltoreq. y .ltoreq.0.4 and z is within the range of 0.05 .ltoreq. z .ltoreq.(x/2+0.5). The invention further provides a method for producing the oxide superconductor which comprises firing a composition of the formula (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.3 O.sub.7-z wherein R is at least one rare earth element selected from the group consisting of Tm, Yb and Lu, x is within the range of 0.1 .ltoreq..times..ltoreq.0.5 and y is within the range of 0.1 .ltoreq.y .ltoreq.0.4 at a temperature of from 750.degree. C. to the melting temperature of the composition under an oxygen partial pressure P(O.sub.

Abstract: An apparatus for producing a superconducting oxide film with stable properties by metal organic chemical vapor deposition, suitable for mass production, is provided with a gas analyzer comprising a differential pressure meter 38 between a raw material gas collector tube 35 provided in a transfer line 8 for leading a raw material gas to a film forming chamber 10 and a bypass line 37, a dilution gas line 49 interlocked with the differential pressure meter 38 and for leading a dilution gas to the raw material gas collector tube 35, a gas separation column 42 branched from the bypass line, a gas detector 31 connected to the gas separation column 42, flow rate controllers 50 for carrier gases 43 and 45 and a thermostat 13 for heating all the lines.

Abstract: A superconducting material is disclosed which includes oxides of metals having the following composition:(Pb.sub.1-z Cu.sub.z) ((Sr.sub.1-y Ba.sub.y).sub.1-v Ca.sub.v).sub.2 (A.sub.1-x Ca.sub.x)Cu.sub.2wherein A is at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Ho, Er, Yb and mixtures of at least one of Y, La, Nd, Sm, Eu, Gd, Ho, Er and Yb with at least one of Tb, Tm and Lu, x, y, v and z are numbers satisfying the following conditions:0.ltoreq.x.ltoreq.0.4,0.1.ltoreq.y<0.7,0.ltoreq.v.ltoreq.0.2x, and2y-0.4.ltoreq.z.ltoreq.2y+0.2with the proviso that 0.6-x.ltoreq.z<1.0 when 0.ltoreq.x.ltoreq.0.2 and that 0.4.ltoreq.z<1.0 when 0.2.ltoreq.x.ltoreq.0.4. The superconducting material is produced by providing a blend of compounds of the metals in the metal oxides, and heating the blend at an oxygen partial pressure P of at least 0.001 atm and temperature of (860+40logP) .degree.C. to (1060+40logP) .degree.C.

Abstract: In a ceramic superconducting composition, Ag20 is added thereto in an amount of 0.1 wt. % to 70 wt. % per mole of LaBa2Cu3O3-.delta.. The critical current density of the ceramic superconducting composition is affected by heat treatment conditions. The critical electric current density of the ceramic superconducting composition is increased when it is prepared through heat treatment while controlling the partial pressure of oxygen in a heat treatment atmosphere in steps with successive stages including a temperature-elevating step, a sintering step, a temperature-lowering step, and an annealing step.

Abstract: A method for producing an oxide superconductor formed according to a chemical composition formula (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.4 O.sub.8 and having a transition temperature of 77K or above, comprising the step of causing a reaction between (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.3 O.sub.7-z and a Cu material such as CuO, wherein R stands for one or more rare earth elements selected from the group consisting of Y, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm and Yb, and wherein 0.01.ltoreq.x.ltoreq.0.25, 0.ltoreq.y.ltoreq.0.5, and 0.ltoreq.z.ltoreq.1. The advantage of this production method is that this production method does not require a hot static pressing process which takes a long time.

Abstract: A process for forming a thin oxide film on an underlying surface adapted for film formation thereon according to a radio frequency magnetron sputtering method using an oxide target(s). The excitation frequency is higher than 13.56 MHz and provides a lower negative target self-bias voltage permitting improved film formation.

Abstract: An apparatus for manufacturing a multielement sintered material is provided, more particularly an appartus of the automated type which weighs and mixes predetermined amounts of powdery elements, molds the mixed elements and then sinters them.