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US5017548A
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Method of producing high-temperature superconducting ceramics material by mechanical orientation
Assignee: KYUSHU UNIVERSITY OF 10-1 HAKOZAKI 6-CHOME HIGASHI-KU FUKUOKA CITY FUKUOKA PREF JAPAN
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Filing: 1989-12-01
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Granted: 1991-05-21
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Expires: 2009-12-01
Abstract
Abstract A method for producing high-temperature superconducting ceramic material through mechanical orientation including mixing starting materials in powdered form in proportions effective to produce a high-temperature superconducting oxide ceramic having anisotropic crystal grains and shaping the mixture. Next, the shaped mixture is calcined at a temperature ranging from 600° to 900° C. and fired at a temperature higher than 1,000° C. in an oxygen atmosphere for a time effective to produce a superconducting oxide ceramic having crystal grains. According to the invention, the superconductive oxide ceramic is then pulverized into particles having either a plate-like form or a needle-like form based on the anisotropic form of the crystal grains. Particles of a selected size are placed into a vessel and vibrated with an acoustic vibrator means under conditions effective to cause the pulverized particles to turn toward a common preferred orientation to provide oriented particles. Then, the oriented particles are shaped by applying pressure to the vessel in a direction perpendicular to the common preferred orientation and fired at a temperature ranging from 900° to 1,000° C. for a time effective to produce the high-temperature superconducting oxide ceramic material with anisotropic crystal structure.
Inventors
- 👤 Kazuyoshi Hirakawa
- 👤 Hisao Kuriyaki
- 👤 Xu-guang Zheng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:01
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/45; C04B35/4504; C04B35/4508; H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; Y; Y10; Y10S; Y10S505/00; Y10S505/725
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
239 words
A method for producing high-temperature superconducting ceramic material through mechanical orientation, the method comprising the steps of: a. mixing starting materials in powdered form and in proportions effective to produce a mixture for a high-temperature superconducting oxide ceramic having anisotropic crystal grains; b. shaping the mixture to provide a shaped mixture; c. calcining the shaped mixture at a temperature ranging from 600° to 900° C. to provide a calcined mixture; d. firing the calcined mixture at a temperature higher than 1,000° C. in an oxygen atmosphere for a time effective to produce a superconducting oxide ceramic having crystal grains, and cooling the superconducting oxide ceramic; e. pulverizing the superconductive oxide ceramic of step d with means effective to pulverize same into particles having one of a plate-like form and a needle-like form based on the anisotropic form of the crystal grains to provide pulverized particles; f. placing pulverized particles of a selected size into a vessel; g. vibrating the vessel with an acoustic vibrator means under conditions effective to cause the pulverized particles placed therein to turn toward a common preferred orientation to provide oriented particles; h. shaping the oriented particles by applying pressure to the vessel in a direction perpendicular to the common preferred orientation; and i. firing the shape and oriented particles at a temperature ranging from 900° to 1,000° C. for a time effective to produce a high-temperature superconducting oxide ceramic material with anisotropic crystal structure.
Claim 2
Independent Claim
239 words
A method for producing high-temperature superconducting ceramic material through mechanical orientation, the method comprising the steps of: a. mixing starting materials in powdered form and in proportions effective to produce a mixture for a high-temperature superconducting oxide ceramic having anisotropic crystal grains; b. shaping the mixture to provide a shaped mixture; c. calcining the shaped mixture at a temperature ranging from 600° to 900° C. to provide a calcined mixture; d. firing the calcined mixture at a temperature higher than 1,000° C. in an oxygen atmosphere for a time effective to produce a superconducting oxide ceramic having crystal grains, and cooling the superconducting oxide ceramic; e. pulverizing the superconductive oxide ceramic of step d with means effective to pulverize same into particles having one of a plate-like form and a needle-like form based on the anisotropic form of the crystal grains to provide pulverized particles; f. placing pulverized particles of a selected size into a vessel; g. vibrating the vessel with an acoustic vibrator means under conditions effective to cause the pulverized particles placed therein to turn toward a common preferred orientation to provide oriented particles; h. shaping the oriented particles by applying pressure to the vessel in a direction perpendicular to the common preferred orientation; and i. firing the shape and oriented particles at a temperature ranging from 900° to 1,000° C. for a time effective to produce a high-temperature superconducting oxide ceramic material with anisotropic crystal structure.
Claim 3
Dependent Claim
31 words
The method according to claim 1, wherein the superconducting oxide ceramic material has a general chemical formula YBa.sub.2 Cu.sub.3 O.sub.7-x, wherein x is a positive number not larger than 0.2 (0<x≦0.2).
Claim 4
Dependent Claim
22 words
The method according to claim 1, wherein calcining in step (c) and firing in step (i) are performed in an oxygen atmosphere.
Claim 5
Independent Claim
262 words
A method for producing a high-temperature superconducting YBa 2 Cu 3 O 7-x ceramic through mechanical orientation, the method comprising the steps of: a. mixing starting materials in powdered form and in proportions effective to produce a mixture for a high-temperature superconducting oxide ceramic consisting of YBa 2 Cu 3 O 7-x and having anisotropic crystal grains; b. shaping the mixture to provide a shaped mixture; c. calcining the shaped mixture at a temperature ranging from 600° to 900° C. in an oxygen atmosphere to provide a calcined mixture; d. firing the calcined mixture at a temperature higher than 1,000° C. in an oxygen atmosphere for a time effective to produce a superconducting oxide ceramic having crystal grains, and cooling the superconducting oxide ceramic; e. pulverizing the superconductive oxide ceramic of step d with means effective to pulverize same into particles having one of the plate-like form and a needle-like form based on the anisotropic form of the crystal grains to provide pulverized particles; f. placing pulverized particles of a selected size into a vessel; g. vibrating the vessel with an acoustic vibrator means under conditions effective to cause the pulverized particles placed therein to turn toward a common preferred orientation to provide oriented particles; h. shaping the oriented particles by applying pressure to the vessel in a direction perpendicular to the common preferred orientation; and i. firing the shape and oriented particles at a temperature ranging from 900° to 1,000° C. in an oxygen atmosphere for a time effective to produce a high-temperature, superconducting oxide ceramic material with anisotropic crystal structure.
Claim 6
Independent Claim
262 words
A method for producing a high-temperature superconducting YBa 2 Cu 3 O 7-x ceramic through mechanical orientation, the method comprising the steps of: a. mixing starting materials in powdered form and in proportions effective to produce a mixture for a high-temperature superconducting oxide ceramic consisting of YBa 2 Cu 3 O 7-x and having anisotropic crystal grains; b. shaping the mixture to provide a shaped mixture; c. calcining the shaped mixture at a temperature ranging from 600° to 900° C. in an oxygen atmosphere to provide a calcined mixture; d. firing the calcined mixture at a temperature higher than 1,000° C. in an oxygen atmosphere for a time effective to produce a superconducting oxide ceramic having crystal grains, and cooling the superconducting oxide ceramic; e. pulverizing the superconductive oxide ceramic of step d with means effective to pulverize same into particles having one of the plate-like form and a needle-like form based on the anisotropic form of the crystal grains to provide pulverized particles; f. placing pulverized particles of a selected size into a vessel; g. vibrating the vessel with an acoustic vibrator means under conditions effective to cause the pulverized particles placed therein to turn toward a common preferred orientation to provide oriented particles; h. shaping the oriented particles by applying pressure to the vessel in a direction perpendicular to the common preferred orientation; and i. firing the shape and oriented particles at a temperature ranging from 900° to 1,000° C. in an oxygen atmosphere for a time effective to produce a high-temperature, superconducting oxide ceramic material with anisotropic crystal structure.
References Cited (Backward Citations)
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