Preparation method for ceramic composite material, ceramic composite material, and wavelength converter

Patent metadata

Field	Value
Publication number	US-2020123063-A1
Application number	US-201716468112-A
Country	US
Kind code	A1
Filing date	Nov 3, 2017
Priority date	Dec 9, 2016
Publication date	Apr 23, 2020
Grant date	—

Abstract

A preparation method for a ceramic composite material, a ceramic composite material, and a wavelength converter. The preparation method comprises: preparing an aluminium salt solution and a fluorescent powder; dispersing the fluorescent powder into a buffer solution having a pH 4.5-5.5 to obtain a suspension; titrating the suspension with the aluminium salt solution to obtain a fluorescent powder coated with Al 2 O 3 hydrate film; calcining the fluorescent powder coated with Al 2 O 3 hydrate film to obtain a Al 2 O 3 -coated fluorescent powder; mixing aluminium oxide powder with a particle size of 0.1 μm-1 μm and aluminium oxide powder with a particle size of 1 μm-10 μm to obtain mixed aluminium oxide powder; mixing the Al 2 O 3 -coated fluorescent powder and the mixed aluminium oxide powder to obtain mixed powder, the Al 2 O 3 -coated fluorescent powder being present in 40%-90% by weight of the mixed powder; and pre-pressing and sintering the mixed powder to obtain the ceramic composite material.

First claim

1 . A method for preparing a ceramic composite material, comprising:
preparing an aluminum salt solution and a fluorescent powder according to a mass ratio of Al 2 O 3 to fluorescent powder of (0.1 to 1):100; dispersing the fluorescent powder in a buffer solution with a pH value of 4.5 to 5.5 to obtain a suspension; titrating the suspension with the aluminum salt solution to obtain a fluorescent powder coated with an Al 2 O 3 hydrate film; calcining the fluorescent powder coated with the Al 2 O 3 hydrate film to obtain an Al 2 O 3 -coated fluorescent powder; mixing an alumina powder having a particle diameter of 0.1 μm to 1 μm and an alumina powder having a particle diameter of 1 μm to 10 μm according to a molar ratio of 100:(0.1 to 5), so as to obtain a mixed alumina powder; mixing the Al 2 O 3 -coated fluorescent powder and the mixed alumina powder to obtain a mixed powder, wherein the Al 2 O 3 -coated fluorescent powder accounts for 40% to 90% by weight of the mixed powder; and pre-pressing and sintering the mixed powder to obtain the ceramic composite material.

2 . The method for preparing the ceramic composite material according to claim 1 , wherein the fluorescent powder comprises at least one Ce 3+ -doped fluorescent powder selected from the group consisting of Ca 3 Al 2 Si 3 O 12 , Ca 3 Sc 2 Si 3 O 12 , Gd 3 Al 5 O 12 , Gd 3 Ga 5 O 12 , Tb 3 Al 5 O 12 , Tb 3 Ga 5 O 12 , Y 3 Al 5 O 12 , Y 3 Ga 5 O 12 , Lu 3 Al 5 O 12 , Lu 3 Ga 5 O 12 and Y 3 Mg 2 AlSi 2 O 12 .

3 . The method for preparing the ceramic composite material according to claim 2 , wherein the fluorescent powder has a particle diameter in a range of 13 μm to 20 μm.

4 . The method for preparing the ceramic composite material according to claim 1 , wherein the aluminum salt solution has a concentration of 0.01 mol/L to 1 mol/L.

5 . The method for preparing the ceramic composite material according to claim 1 , wherein in the step of titrating the suspension with the aluminum salt solution, a temperature of the suspension is in a range of 40° C. to 70° C., a stirring rate is in a range of 100 r/min to 300 r/min, and a titrating rate is in a range of 5 mL/min to 50 mL/min.

6 . The method for preparing the ceramic composite material according to claim 1 , wherein a calcination temperature is in a range of 300° C. to 600° C., and a calcination duration is in a range of 2 h to 5 h.

7 . The method for preparing the ceramic composite material according to claim 1 , wherein the step of pre-pressing is carried out under a pressure of 5 MPa to 15 MPa.

8 . The method for preparing the ceramic composite material according to claim 1 , wherein sintering is carried out in an argon atmosphere, a sintering temperature is in a range of 1250° C. to 1550° C., a holding time is in a range of 30 min to 360 min, and a sintering pressure is in a range of 30 MPa to 200 MPa.

9 . The method for preparing the ceramic composite material according to claim 1 , wherein in the step of mixing the alumina powder having a particle diameter of 0.1 μm to 1 μm and the alumina powder having a particle diameter of 1 μm to 10 μm according to the molar ratio of 100:(0.1 to 5), an alumina powder having a particle diameter of 0.01 μm to 0.1 μm is additionally added, wherein a molar ratio of the alumina powder of 0.01 μm to 0.1 μm to the alumina powder of 0.1 μm to 1 μm is (0.1 to 1):100.

10 . The method for preparing the ceramic composite material according to claim 1 , wherein the step of mixing the Al 2 O 3 -coated fluorescent powder and the mixed alumina powder comprises:
dispersing the mixed alumina powder into a PEG 4000-ethanol solution having a concentration of 1% to 3% by weight, placing the obtained mixture into a ball-milling tank and performing ball-milling for 6 h to 24 h; and adding the Al 2 O 3 -coated fluorescent powder into the ball-milling tank, and further performing ball-milling for 30 min to 60 min.

11 . A ceramic composite material, comprising an alumina matrix, a fluorescent powder uniformly distributed in the alumina matrix, and scattering centers uniformly distributed in the alumina matrix, wherein the alumina matrix is an alumina ceramics, the scattering centers are alumina particles, the alumina particles each have a particle diameter of 1 μm to 10 μm, and the fluorescent powder has a particle diameter of 13 μm to 20 μm.

12 . A wavelength converter comprising the ceramic composite material according to claim 11 .

13 . The method for preparing the ceramic composite material according to claim 5 , wherein after finishing the step of titrating the suspension with the aluminum salt solution, further comprising:
maintaining the temperature of the suspension and stirring for 1 h to 2 h, and adjusting a pH value into a range of 6 to 7 with a sodium hydroxide solution.

14 . The method for preparing the ceramic composite material according to claim 5 , wherein before the step of calcining the fluorescent powder coated with the Al 2 O 3 hydrate film to obtain an Al 2 O 3 -coated fluorescent powder, further comprising:
centrifuging the fluorescent powder coated with the Al 2 O 3 hydrate film; washing the fluorescent powder coated with the Al 2 O 3 hydrate film with water, dehydrating for 3 to 5 times, and then drying at a temperature in a range of 75° C. to 85° C.

15 . The method for preparing the ceramic composite material according to claim 1 , wherein the Al 2 O 3 -coated fluorescent powder accounts for 50% to 70% by weight of the mixed powder.

16 . The ceramic composite material according to claim 11 , wherein the fluorescent powder comprises at least one Ce 3+ -doped fluorescent powder selected from the group consisting of Ca 3 Al 2 Si 3 O 12 , Ca 3 Sc 2 Si 3 O 12 , Gd 3 Al 5 O 12 , Gd 3 Ga 5 O 12 , Tb 3 Al 5 O 12 , Tb 3 Ga 5 O 12 , Y 3 Al 5 O 12 , Y 3 Ga 5 O 12 , Lu 3 Al 5 O 12 , Lu 3 Ga 5 O 12 and Y 3 Mg 2 AlSi 2 O 12 .

17 . The ceramic composite material according to claim 11 , wherein the particle diameter of the fluorescent powder is 15 μm to 17 μm.

Assignees

• Appotronics Corp Ltd

Inventors

• Li Qian
• Xu Yanzheng

Classifications

• C04B35/195

  Alkaline earth aluminosilicates, e.g. cordierite {or anorthite} · CPC title

• C01F7/028

  Beta-aluminas · CPC title

• C04B35/117

  Composites · CPC title

• C04B35/62813 Primary

  Alumina or aluminates · CPC title

• C04B2235/5436

  micrometer sized, i.e. from 1 to 100 micron · CPC title