Ceramic and method for preparing the same

Patent metadata

Field	Value
Publication number	US-2016304404-A1
Application number	US-201615192721-A
Country	US
Kind code	A1
Filing date	Jun 24, 2016
Priority date	Dec 30, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

A ceramic and a method for preparing a ceramic are provided. The ceramic includes an alumina and an oxygen-containing compound of strontium having a perovskite structure.

First claim

1 . A ceramic comprising an alumina and an oxygen-containing compound of strontium having a perovskite structure.

2 . The ceramic of claim 1 , wherein the oxygen-containing compound of strontium comprises Sr a A b O c and Sr x E y O z , where A represents at least one of tantalum and niobium; E represents at least one selected from the group consisting of cobalt, iron and manganese.

3 . The ceramic of claim 2 , wherein a ranges from 1.5 to 2.5, b ranges from 1.5 to 2.5, c ranges from 6.5 to 7.5, y ranges from 0.9 to 1.1, and z ranges from 2.7 to 3.3.

4 . The ceramic of claim 1 , wherein the red-green value of the ceramic ranges from 0.06 to 0.07, and the blue-yellow value ranges from 0.032 to −0.02.

5 . The ceramic of claim 1 , wherein an intensity of light reflected by a surface of the ceramic ranges from 43 to 44.

6 . The ceramic of claim 2 , wherein the toughness of the ceramic is in a range of 6 MPa m 1/2 to 8 MPa m 1/2 .

7 . A method of preparing a ceramic, comprising:
providing a first uniform slurry of a basis material, an additive, a flexibilizer, a black stain and a sintering aid in an organic solvent; providing a second uniform slurry of the organic solvent and a binder; drying the second slurry to form a spherical powder; and dry pressing and sintering the spherical powder to form the ceramic, wherein the basis material comprises alumina, the additive comprises strontium carbonate, and an oxygen-containing compound of strontium having a perovskite structure is obtainable by a reaction of the additive with at least one of the flexibilizer and the black stain during the sintering process.

8 . The method of claim 7 , wherein based on 100 weight parts of the basis material, the amount of the additive ranges from 1 weight part to 4 weight parts, the amount of the flexibilizer ranges from 0.2 weight parts to 3 weight parts, the amount of the black stain ranges from 0.5 weight parts to 5 weight parts, the amount of the sintering aids ranges from 0.2 weight parts to 0.5 weight parts, and the amount of the binder ranges from 0.4 weight parts to 0.6 weight parts.

9 . The method of claim 7 , wherein the flexibilizer comprises at least one of tantalum pentoxide and niobium pentoxide.

10 . The method of claim 7 , wherein the black stain comprises at least one of manganese carbonate and a mixture of cobalt carbonate and iron carbonate.

11 . The method of claim 7 , wherein the step of sintering is performed by heating under the following temperature conditions:
increasing the temperature from room temperature to 600° C. in 400 minutes, and maintaining at 600° C. for 120 minutes; increasing the temperature from 600° C. to 1150° C. in 300 minutes and maintaining at 1150° C. for 120 minutes; increasing the temperature from 1150° C. to 1300° C. in 150 minutes and maintaining at 1300° C. for 120 minutes; increasing the temperature from 1300° C. to 1350° C. in 50 minutes and maintaining at 1350° C. for 120 minutes; and reducing the temperature from 1350° C. to 900° C. in 150 minutes.

12 . The method of claim 7 , further comprising adding a dispersant into the first uniform slurry before providing the second uniform slurry.

13 . The method of claim 12 , wherein the dispersant is at least one selected from the group consisting of hydroxypropyl methylcellulose, sodium carboxymethylcellulose and triethanolamine.

14 . The method of claim 7 , wherein the sintering aid comprises at least one of silicon dioxide and titanium dioxide.

15 . The method of claim 7 , wherein the binder comprises at least one of polyvinyl alcohol and polyethylene glycol 4000.

16 . The method of claim 15 , wherein a molar ratio of polyvinyl alcohol to polyethylene glycol 4000 is in a range from 1:1 to 1:2.

17 . The method of claim 7 , further comprising polishing the ceramic.

18 . A ceramic comprising an alumina and an oxygen-containing compound of strontium having a perovskite structure that is obtained by the method of claim 7 .

19 . The ceramic of claim 2 , wherein the red-green value of the ceramic ranges from 0.06 to 0.07, and the blue-yellow value ranges from −0.032 to −0.02.

20 . The method of claim 8 , wherein the flexibilizer comprises at least one of tantalum pentoxide and niobium pentoxide.

Assignees

• Byd Co Ltd

Inventors

• Chen Ge
• Lin Yongzhao
• Lin Xinping

Classifications

• C04B35/117 Primary

  Composites · CPC title

• C04B2235/74

  Physical characteristics · CPC title

• C04B2235/3255

  Niobates or tantalates, e.g. silver niobate · CPC title

• C04B35/634

  Polymers (C04B35/636 takes precedence) · CPC title

• C04B2235/3268

  Manganates, manganites, rhenates or rhenites, e.g. lithium manganite, barium manganate, rhenium oxide · CPC title