JPS63315565A - Superconducting material composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition being a specific composition consisting of Y, Ba, Cu, Tl and oxygen and useful as a material for high temperature superconductor capable of using at temperature of liquid nitrogen. CONSTITUTION:The aimed superconducting material composition expressed by the formula YxBayCuzTlvOw wherein Y, Ba, Cu and Tl are yttrium, barium, copper and thallium, respectively; x, y, z and v are in the range of the equations 0<x/(x+y+z)<1; 0<y/(x+y+z)<1; 0<z/(x+y+z)<1; 0<v/(x+y+z)<0.3; w is atomic number of oxygen satisfying the required valence of other element.

Description

[Detailed Description of the Invention] Although superconducting materials are expected to have a wide range of applications in industries such as magnetically levitated linear motor cars, current practical materials have a low critical temperature and cannot be used in liquid helium conditions. The reality is that it does not live up to expectations because it is limited.

Its appearance is eagerly awaited. Recently LA, 3a, C
These materials meet expectations as current high-temperature superconducting materials such as oxides made of u, YXBa, and Cu. That is, in the present invention, in the formula Yx Bay Cuz TJIv Ow, Y represents yttrium, Ba represents barium, Cu represents copper, TJI represents thallium, and " e 7 +
Z I Y is O<”/x+3'+z<1.0
<3' / x -) - y + z < 1, o
< Z/ x + y + z < 1, o < v/x+
It is a new superconducting material composition that falls within the range of y + z < O-3, where W is the number of oxygen atoms that adds 1 to the required valence of other elements, and compared to conventional superconducting materials, Superconductivity can be achieved at high temperatures. Appropriate preparation methods can be selected depending on the intended use; one example is
This is an oxide mixing firing method in which yttrium oxide, barium carbonate, steel oxide, and thallium oxide are mixed at a predetermined amount and a solid phase reaction is performed by heating at about 850 to 1000°C. Various other coprecipitation methods known to those skilled in the art for producing oxide compositions,
A precipitation mixing method, a salt decomposition method, etc. can be used. Therefore, as raw materials for each element, oxides, various inorganic salts, organic salts, etc. can be used. Depending on the application, a CVD method, a sputtering method, a vapor deposition method, etc. are selected. For this reason, as raw materials, in addition to individual elements, metals, etc., raw materials suitable for the preparation method can be selected.

The present invention will be explained below with reference to Examples.

Example 1 Commercially available special grade reagent YzOs 3.73y, BaO10
,272, Tf1202.12ri, Cll0 7.96
Weighed more F, mixed for 1 hour in a rice cooker, and then heated to 900°C.
It was baked for 12 hours. After cooling, the fired powder was lysed and formed into tablets, and then heated again in an electric furnace at 900°C for 12
Baked for an hour.

When the fired product was measured using the four-terminal method, the temperature at which the resistance became completely zero was 92.7.

The magnetic susceptibility also showed diamagnetism from 92.7K.

The composition of the fired product is black, and the composition is Yo, 3s Bao,
67 Tfio, t Cux de Atsuno.

Examples 2 to 6 Baked products were prepared in the same manner as in Example 1 using the charging compositions shown in Table IK. The results are shown in Table 1.

Table 1

Claims (1)

[Claims] 1) In the formula YxBayCuzTlvOw, Y represents yttrium, Ba represents barium, Cu represents copper, and Tl represents thallium, and x, y, z, and v are 0<x/(x+y+z)<1 ,0<y/(x+y+z)
<1, 0<z/(x+y+z)<1,0<v/(x+y
+z)<0.3, where w represents the number of oxygen atoms that satisfies the required valence of other elements.