1. A preparation method of three-color transparent fluorescent ceramic capable of adjusting white light of different degrees is characterized by comprising the following steps: the method comprises the following steps:

step1, weighing high-purity oxide raw material powder according to the designed stoichiometric ratio of Ce to YAG, Ce to Mn to YAG and Ce to LuAG, and removing impurities for pretreatment;

step2, respectively adding sintering aid and Al into the powder₂O₃Grinding balls and an absolute ethyl alcohol solvent to form a premixed solution, and mixing and ball-milling the premixed solution for 24-36 hours to respectively obtain three ceramic slurries including YAG (cerium-doped yttrium aluminum), Ce, Mn, YAG and LuAG;

step3, drying three ceramic slurries including YAG, Ce, Mn, YAG and LuAG, sieving and calcining in a muffle furnace to obtain three ceramic raw material powders including YAG, Ce, Mn, YAG and LuAG;

step4, respectively preparing slurry with high solid content required by the formation of Isobam gel by using the three ceramic raw material powders of YAG, Ce, Mn, YAG and LuAG;

step5, pouring the slurry into a mould in sequence respectively to obtain ceramic biscuit;

and Step6, carrying out cold isostatic pressing, drying, binder removal, vacuum sintering and polishing on the ceramic biscuit to obtain the three-color transparent fluorescent ceramic capable of adjusting white light of different degrees.

2. The method of claim 1, wherein: in Step1, the raw material powder comprises aluminum oxide, yttrium oxide, cerium oxide, manganese carbonate and lutetium oxide, and the purity of the raw material powder is more than 99.99%; the impurity removal treatment adopts a calcination method.

3. The method of claim 1, wherein: in Step2, the sintering aid is MgO and SiO₂Mixture of (2), sintering aid, Al₂O₃The dosage ratio of the grinding ball, the absolute ethyl alcohol and the raw material powder is 1: 600: 240: 200.

4. the method of claim 1, wherein: in Step3, evaporating for 24-48 h in a constant-temperature oven at 40-100 ℃; the calcination temperature is 800-1000 ℃, and the heat preservation is carried out for 8-24 h.

5. The method of claim 1, wherein: in Step4, the slurry adopts Isobam104# as a gel agent; the high solid content is 45 vol.% to 50 vol.%.

6. The method of claim 1, wherein: in Step5, the mould is a bulb-shaped mould, and is dried for 48-72 hours at room temperature.

7. The method of claim 1, wherein: step6, performing cold isostatic pressing for 5-20 min under the condition of 100-200 MPa; the drying process is drying for 4-8 hours in an oven at 100-120 ℃; the temperature rising speed of room temperature to 450 ℃ is 0.5-2 ℃/min, the temperature rising speed of 450-800 ℃ is 0.5-3 ℃/min, and the heat is preserved for 2-6 h at 800 ℃; the vacuum sintering process comprises the following steps: at room temperature, firstly heating to 200 ℃ at a speed of 5-10 ℃/min, preserving heat for 10-30 min, secondly heating to 1000 ℃ at a speed of 10-20 ℃/min, preserving heat for 10-30 min, then heating to 1650 ℃ at a speed of 1-5 ℃/min, preserving heat for 6-10 h, and finally cooling to room temperature at a speed of 5-10 ℃/min, wherein the vacuum degree is maintained at 1 x 10 in the sintering process^-2～1×10^-5 Pa。

Background

As a solid semiconductor device capable of electro-optical conversion, an LED has been widely used because of its advantages in the field of illumination, such as high efficiency, low power consumption, long life, and low power consumption. In particular, "blue LED chip + yellow phosphor" is one of the important combination ways to realize white LED illumination.

However, the conventional packaging technology uses a phosphor dispensing packaging process. The biggest defect of the technology is that the epoxy resin or silica gel has poor high temperature resistance and ultraviolet irradiation energy, the transparency and the refractive index of the dispensing layer are reduced, the luminous efficiency and the light intensity distribution of the device are influenced, and the service life of the white light LED is greatly shortened. The fluorescent glass can reduce the light transmittance of the fluorescent glass due to the difference between the glass substrate and the fluorescent powder. Therefore, the use of transparent fluorescent ceramics greatly improves this defect. The fluorescent material aims at the defect that white light emitted by yellow Ce: YAG transparent fluorescent ceramic under the excitation of a blue LED chip is low in color rendering index due to the lack of doping of red light, namely, cold white light is generated. According to the principle of three primary colors of light, the gel casting method is adopted to obtain the red, green and yellow transparent ceramics, the suspension device is utilized to lead the three-color transparent ceramics to be suspended and rotated, and then the LD laser is used for excitation, thus generating high-quality white light; white light of different degrees can be obtained by exciting different positions, and the fluorescent ceramic has better thermal stability compared with fluorescent powder and fluorescent glass.

In the prior art, many YAG-based transparent fluorescent ceramics are available, for example, CN 110597002 a adopts a cutting and adhering method to form a multi-color wheel, but the cutting process is complicated, and the difference between epoxy resin and ceramics required for adhering affects the refraction efficiency of light, and the color wheel may break when a high temperature is encountered; the patent CN 110256072 a utilizes a dry pressing method to press red, green and yellow ceramics, but the mold is complicated and the red powder is nitride red powder non-YAG based ceramic powder or has a certain influence on the light effect.

Disclosure of Invention

The invention aims to solve the technical problem of obtaining the three-color transparent fluorescent ceramic capable of adjusting white light of different degrees, which aims to adopt a method of 'blue LD chip + yellow, red and green three-color fluorescent ceramic' to generate high-quality white light, fully mix the blue, yellow, red and green four-color light in a suspension rotation mode and increase the heat dissipation performance of the fluorescent ceramic.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a preparation method of three-color transparent fluorescent ceramic capable of adjusting white light of different degrees comprises the following steps of: YAG transparent ceramic, Ce, Mn: YAG transparent ceramic, Ce: under the excitation of blue LD laser, LuAG transparent ceramic is mixed with own yellow light, red light and green light in different proportions to generate white light of different degrees. Secondly, a gel forming method is adopted to obtain three-color ceramic in a bulb shape, so that the ceramic can be well illuminated. Finally, the magnetic suspension device is used for suspending and rotating the three-color ceramic to mix the blue, yellow, red and green lights more uniformly, and the heat dissipation effect can be enhanced by rotation.

The preparation method comprises the following steps:

step1, weighing high-purity oxide raw material powder according to the designed stoichiometric ratio of Ce to YAG, Ce to Mn to YAG and Ce to LuAG, and removing impurities for pretreatment;

step2, respectively adding sintering aid and Al into the powder₂O₃Grinding balls and an absolute ethyl alcohol solvent to form a premixed solution, and mixing and ball-milling the premixed solution for 24-36 hours to respectively obtain three ceramic slurries including YAG (cerium-doped yttrium aluminum), Ce, Mn, YAG and LuAG;

step3, drying three ceramic slurries including YAG, Ce, Mn, YAG and LuAG, sieving and calcining in a muffle furnace to obtain three ceramic raw material powders including YAG, Ce, Mn, YAG and LuAG;

step4, respectively preparing slurry with high solid content required by the formation of Isobam gel by using the three ceramic raw material powders of YAG, Ce, Mn, YAG and LuAG;

step5, pouring the slurry into a mould in sequence respectively to obtain ceramic biscuit;

and Step6, carrying out cold isostatic pressing, drying, binder removal, vacuum sintering and polishing on the ceramic biscuit to obtain the three-color transparent fluorescent ceramic capable of adjusting white light of different degrees.

Preferably, in Step1, the raw material powder comprises alumina, yttrium oxide, cerium oxide, manganese carbonate and lutetium oxide, and the purity of the raw material powder is more than 99.99%; the impurity removal treatment adopts a calcination method.

Preferably, in Step2, the sintering aid is MgO and SiO₂Mixture of (2), sintering aid, Al₂O₃The dosage ratio of the grinding ball, the absolute ethyl alcohol and the raw material powder is 1: 600: 240: 200.

preferably, in Step3, the drying is carried out for 24-48 h in a constant-temperature oven at 40-100 ℃; the calcination temperature is 800-1000 ℃, and the heat preservation is carried out for 8-24 h.

Preferably, in Step4, the slurry adopts Isobam104# as a gelling agent; the high solid content is 45 vol.% to 50 vol.%.

Preferably, in Step5, the mold is a 'bulb' -shaped mold, and the mold is dried for 48-72 hours at room temperature.

Preferably, in Step6, the cold isostatic pressing condition is 5-20 min under 100-200 MPa; the drying process is drying for 4-8 hours in an oven at 100-120 ℃; the temperature rising speed of room temperature to 450 ℃ is 0.5-2 ℃/min, the temperature rising speed of 450-800 ℃ is 0.5-3 ℃/min, and the heat is preserved for 2-6 h at 800 ℃; the vacuum sintering process comprises the following steps: at room temperature, firstly heating to 200 ℃ at a speed of 5-10 ℃/min, preserving heat for 10-30 min, secondly heating to 1000 ℃ at a speed of 10-20 ℃/min, preserving heat for 10-30 min, then heating to 1650 ℃ at a speed of 1-5 ℃/min, preserving heat for 6-10 h, and finally cooling to room temperature at a speed of 5-10 ℃/min, wherein the vacuum degree is maintained at 1 x 10 in the sintering process^-2～1×10^-5 Pa。

Compared with the prior art, the invention has the following beneficial effects:

1. the invention provides a three-color transparent fluorescent ceramic capable of adjusting white light of different degrees and a preparation method thereof.

2. The invention provides three-color transparent fluorescent ceramic capable of adjusting white light of different degrees and a preparation method thereof.

3. The invention provides three-color transparent fluorescent ceramic capable of adjusting white light of different degrees and a preparation method thereof, which can adjust the proportion of yellow, red and green to generate white light of different degrees according to requirements.

Drawings

FIG. 1 is a schematic view of a mold of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention is further described in detail with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and should not be taken to limit the scope of the invention.

Example 1

A transparent fluorescent ceramic capable of adjusting three colors of white light with different degrees and a preparation method thereof comprise the following steps:

step1, according to (Y)_0.95%Ce_0.5%)₃Al₅O₁₂、(Y_0.95%Ce_0.5%)₃(Al_0.95%Mn_0.5%)₅O₁₂、(Lu_0.95%Ce_0.5%)₃A_l5O₁₂The stoichiometric ratio of (A) to (B) is respectively weighed high purity nanometer Y₂O₃Powder (purity)>99.99%) 34.214 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 25.761 g, high purity CeO₂Powder (purity)>99.99%) 0.026 g; high purity nano Y₂O₃Powder (purity)>99.99%) 34.210 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 25.745 g, high purity CeO₂Powder (purity)>99.99%) 0.026 g, high purity MnCO₃Powder (purity)>99.99%) 0.029 g; high-purity nano Lu₂O₃Powder (purity)>99.99%) 42.026 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 17.956 g, high purity CeO₂Powder (purity)>99.99%) 0.018 g, and impurity removal pretreatment;

step2, use of sintering aid SiO₂0.2 g of MgO and 0.1g of high purity Al₂O₃180 g of grinding balls and 72 ml of absolute ethyl alcohol are fully stirred and then put into a ball milling tank, and mixed and ball milled for 24 hours to obtain mixed slurry;

step3, placing the mixed slurry in a constant-temperature oven at 40 ℃ for drying for 48h, sieving, placing the sieved powder in a muffle furnace for calcining, heating to 1000 ℃ from room temperature, preserving heat for 8h, and naturally cooling to obtain raw material powder for gel injection molding;

step4, adding 0.3 g of Isobam104# into 30 g of deionized water by adopting a PIBM gel casting system, adjusting the pH to 11 by using tetramethylammonium hydroxide, adopting 0.24 g of ammonium citrate dispersant, adding 60 g of raw material powder, fully ball-milling to prepare ceramic slurry with the solid content of 45 vol.%, and then carrying out defoaming treatment by using a vacuum defoaming machine to obtain transparent ceramic slurry;

and Step5, pouring the slurry into a special mold, and drying for 48 hours at room temperature to obtain a three-color transparent ceramic biscuit.

And Step7, carrying out cold isostatic pressing on the three-color transparent ceramic biscuit, wherein the pressure is 200 MPa, and the time is 5 min. Then carrying out drying treatment: putting into a 100 ℃ oven for heat preservation for 8 h. Drying, removing glue, heating to 450 deg.C at 2 deg.C/min from room temperature, heating to 800 deg.C at 3 deg.C/min, and maintaining for 2 hr. Finally vacuum sintering, heating the room temperature to 200 ℃ at a speed of 10 ℃/min, preserving heat for 10 min, heating the room temperature to 1000 ℃ at a speed of 10 ℃/min again, preserving heat for 10 min, heating the room temperature to 1650 ℃ at a speed of 5 ℃/min, preserving heat for 6 h, cooling the room temperature at a speed of 5 ℃/min, and keeping the vacuum degree at 1 × 10 in the whole sintering process^-2Pa. And polishing to obtain the three-color transparent fluorescent ceramic.

Example 2

A transparent fluorescent ceramic capable of adjusting three colors of white light with different degrees and a preparation method thereof comprise the following steps:

step1, according to (Y)_0.95%Ce_0.5%)₃Al₅O₁₂、(Y_0.95%Ce_0.5%)₃(Al_0.95%Mn_0.5%)₅O₁₂、(Lu_0.95%Ce_0.5%)₃A_l5O₁₂The stoichiometric ratio of (A) to (B) is respectively weighed high purity nanometer Y₂O₃Powder (purity)>99.99%) 34.214 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 25.761 g, high purity CeO₂Powder (purity)>99.99%) 0.026 g; high purity nano Y₂O₃Powder (purity)>99.99%) 34.210 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 25.745 g, high purity CeO₂Powder (purity)>99.99%) 0.026 g, high purity MnCO₃Powder (purity)>99.99%) 0.029 g; high-purity nano Lu₂O₃Powder (purity)>99.99%) 42.026 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 17.956 g, high purity CeO₂Powder (purity)>99.99%) 0.018 g, and impurity removal pretreatment;

step2, use of sintering aid SiO₂0.25 g of MgO and 0.05 g of high purity Al₂O₃180 g of grinding balls and 72 ml of absolute ethyl alcohol are fully stirred and then put into a ball milling tank, and mixed and ball milled for 36 hours to obtain mixed slurry;

step3, placing the mixed slurry in a constant-temperature oven at 100 ℃ for drying for 24 h, sieving, placing the sieved powder in a muffle furnace for calcining, heating to 800 ℃ from room temperature, preserving heat for 24 h, and naturally cooling to obtain raw material powder for gel injection molding;

step4, adding 0.3 g of Isobam104# into 23 g of deionized water by adopting a PIBM gel casting system, adjusting the pH to 11 by using tetramethylammonium hydroxide, adopting 0.3 g of ammonium citrate dispersant, adding 60 g of raw material powder, fully ball-milling to prepare ceramic slurry with the solid content of 50 vol.%, and then carrying out defoaming treatment by using a vacuum defoaming machine to obtain transparent ceramic slurry;

and Step5, pouring the slurry into a special mold, and drying for 60 hours at room temperature to obtain a three-color transparent ceramic biscuit.

And Step7, carrying out cold isostatic pressing on the three-color transparent ceramic biscuit, wherein the pressure is 100 MPa, and the time is 20 min. Then carrying out drying treatment: putting into a 120 ℃ oven for heat preservation for 4 h. Drying, removing gel, and boiling at room temperatureThe temperature is raised to 450 ℃ at the speed of 0.5 ℃/min, then to 800 ℃ at the speed of 0.5 ℃/min, and the temperature is kept for 6 h. Finally vacuum sintering, heating the room temperature to 200 ℃ at a speed of 5 ℃/min, preserving heat for 30 min, heating the room temperature to 1000 ℃ at a speed of 20 ℃/min again, preserving heat for 30 min, heating the room temperature to 1650 ℃ at a speed of 1 ℃/min, preserving heat for 10 h, cooling the room temperature at a speed of 10 ℃/min, and keeping the vacuum degree at 1 × 10 in the whole sintering process^-5Pa. And polishing to obtain the three-color transparent fluorescent ceramic.

Example 3

A transparent fluorescent ceramic capable of adjusting three colors of white light with different degrees and a preparation method thereof comprise the following steps:

step1, according to (Y)_0.95%Ce_0.5%)₃Al₅O₁₂、(Y_0.95%Ce_0.5%)₃(Al_0.95%Mn_0.5%)₅O₁₂、(Lu_0.95%Ce_0.5%)₃A_l5O₁₂The stoichiometric ratio of (A) to (B) is respectively weighed high purity nanometer Y₂O₃Powder (purity)>99.99%) 34.214 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 25.761 g, high purity CeO₂Powder (purity)>99.99%) 0.026 g; high purity nano Y₂O₃Powder (purity)>99.99%) 34.210 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 25.745 g, high purity CeO₂Powder (purity)>99.99%) 0.026 g, high purity MnCO₃Powder (purity)>99.99%) 0.029 g; high-purity nano Lu₂O₃Powder (purity)>99.99%) 42.026 g of high-purity nano Al₂O₃Powder (purity)>99.99%) 17.956 g, high purity CeO₂Powder (purity)>99.99%) 0.018 g, and impurity removal pretreatment;

step2, use of sintering aid SiO₂0.2 g of MgO and 0.1g of high purity Al₂O₃180 g of grinding balls and 72 ml of absolute ethyl alcohol are fully stirred and then put into a ball milling tank, and mixed and ball milled for 30 hours to obtain mixed slurry;

step3, placing the mixed slurry in a constant-temperature oven at 60 ℃ for drying for 36 h, sieving, placing the sieved powder in a muffle furnace for calcining, heating to 900 ℃ from room temperature, preserving heat for 12 h, and naturally cooling to obtain raw material powder for gel injection molding;

step4, adding 0.3 g of Isobam104# into 25 g of deionized water by adopting a PIBM gel casting system, adjusting the pH to 12 by using tetramethylammonium hydroxide, adopting 0.24 g of ammonium citrate dispersant, adding 60 g of raw material powder, fully ball-milling to prepare ceramic slurry with the solid content of 48 vol.%, and then carrying out defoaming treatment by using a vacuum defoaming machine to obtain transparent ceramic slurry;

and Step5, pouring the slurry into a special mold, and drying for 72 hours at room temperature to obtain a three-color transparent ceramic biscuit.

And Step6, carrying out cold isostatic pressing on the three-color transparent ceramic biscuit, wherein the pressure is 150 MPa, and the time is 10 min. Then carrying out drying treatment: putting into a 110 ℃ oven for heat preservation for 6 h. Drying, removing glue, heating to 450 deg.C at 1 deg.C/min from room temperature, heating to 800 deg.C at 1 deg.C/min, and maintaining for 4 hr. Finally vacuum sintering, heating the room temperature to 200 ℃ at 8 ℃/min, keeping the temperature for 20 min, heating the room temperature to 1000 ℃ at 15 ℃/min again, keeping the temperature for 20 min, heating the room temperature to 1650 ℃ at 3 ℃/min, keeping the temperature for 8h, cooling the room temperature at 7 ℃/min, and keeping the vacuum degree at 1 × 10 in the whole sintering process^-3Pa. And polishing to obtain three-color transparent ceramic.