Multi-phase fluorescent ceramics, manufacturing method for multi-phase fluorescent ceramics, and light-emitting device

Abstract

The present application discloses a multi-phase fluorescent ceramic, a method for manufacturing the multi-phase fluorescent ceramic, and a light emitting device, and relates to the technical field of optical elements. The multi-phase fluorescent ceramic includes a luminescent phase, a matrix phase, and pores, the luminescent phase includes a plurality of luminescent crystal grains bonded to one another, the matrix phase includes a plurality of matrix crystal grains bonded to one another, the matrix phase and the luminescent phase are interdigitated and distributed in the multi-phase fluorescent ceramic, and the pores are at least partially distributed in the luminescent phase, at least partially distributed in the matrix phase, and at least partially distributed in the luminescent phase and the matrix phase. 2 O 3 The multi-phase fluorescent ceramic of the present invention can have high scattering performance.

Description

[Technical Field]

[0001] The present application relates to the technical field of optical elements, and more particularly to multi-phase fluorescent ceramics, a method for manufacturing the multi-phase fluorescent ceramics, and a light-emitting device. [Background technology]

[0002] Laser fluorescent light sources have the advantages of long life, high efficiency, and pollution-free, and compared with LED light sources, laser fluorescent light sources have the advantages of high brightness, and compared with pure laser light sources, laser fluorescent light sources are free from speckle problems and are low in cost. Due to the advantages of laser fluorescent light sources, laser fluorescent light sources are widely used in fields such as projection display and lighting.

[0003] As a core component of laser fluorescent light source technology, fluorescent materials have a direct impact on the performance of projection displays and lighting products. While fluorescent ceramics are generally used as conventional fluorescent materials, the scattering performance of these ceramics needs to be improved. Therefore, there is an urgent need for fluorescent materials with good scattering performance. Summary of the Invention [Problem to be solved by the invention]

[0004] In view of this, and to solve the above problems, the present application provides a multi-phase fluorescent ceramic, a method for manufacturing the multi-phase fluorescent ceramic, and a light-emitting device. [Means for solving the problem]

[0005] In order to achieve the above object, the present application provides a multi-phase fluorescent ceramic, the multi-phase fluorescent ceramic including a luminescent phase, a matrix phase, and pores, the luminescent phase includes a plurality of luminescent crystal grains bonded together; the matrix phase includes a plurality of matrix crystal grains bonded to each other, and the matrix phase and the luminescent phase are interdigitated and distributed in the multi-phase fluorescent ceramic; The pores are at least partially distributed within the luminescent phase, at least partially distributed within the matrix phase, and at least partially distributed between the luminescent phase and the matrix phase.

[0006] In order to solve the above problems, another technical solution adopted in the present application provides a method for manufacturing the above multi-phase fluorescent ceramic, the method comprising: mixing a matrix phase material powder, a luminescent phase material powder, and ceramic raw materials including a pore-forming agent to form a mixed powder; compacting the mixed powder to form a green body; heat treating the green body to remove the pore-forming agent; and c) sintering the heat-treated green body to form a multi-phase fluorescent ceramic. [Effects of the Invention]

[0007] To solve the above problems, another technical solution adopted in the present application provides a light emitting device including an excitation light source and the above multi-phase fluorescent ceramic.

[0008] The beneficial effects of the present invention are as follows: Compared with multi-phase fluorescent ceramics in the prior art, for example, multi-phase fluorescent ceramics manufactured by mixing commercially available phosphor powder particles, ceramic particles, and a pore-forming agent and sintering the mixture, the pores are distributed only between the phosphor powder particles and the ceramic particles and between the ceramic particles, whereas the pores in the multi-phase fluorescent ceramic of the present invention are at least partially distributed in the luminescent phase, at least partially distributed in the matrix phase, and at least partially distributed between the luminescent phase and the matrix phase, and therefore the pores distributed in the luminescent phase can improve the scattering performance of the multi-phase fluorescent ceramic. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a structural schematic diagram of a multiphase fluorescent ceramic according to the present application. FIG. [Figure 2]1 is a flowchart of a first embodiment of a method for manufacturing a multi-phase fluorescent ceramic according to the present application. [Figure 3] 1 is a structural schematic diagram of a light emitting device according to the present application. DETAILED DESCRIPTION OF THE INVENTION

[0010] In order to help those skilled in the art understand the technical solution of the present application more clearly, the present application will be described in more detail below with reference to the drawings and specific embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in the present application without any creative work fall within the scope of protection of the present application.

[0011] Currently, multi-phase fluorescent ceramics are generally manufactured by mixing commercially available phosphor powder particles, ceramic particles, and a pore-forming agent, followed by sintering. The luminescent phase of the manufactured multi-phase fluorescent ceramics is the phosphor powder particles, and the phosphor powder particles are single luminescent crystal grains, i.e., approximately spherical single-crystal grains composed of phosphor crystal grains. Therefore, the pores in the manufactured multi-phase fluorescent ceramics are distributed only between the phosphor powder particles and the ceramic particles and between the ceramic particles. In other words, the pores cannot be distributed between the luminescent crystal grains in the luminescent phase.

[0012] In order to overcome the above-mentioned problems, the inventors of the present application have conducted long-term research, development, and testing and found that when manufacturing multi-phase fluorescent ceramics, the luminescent phase in the multi-phase fluorescent ceramics can be synthesized in situ without using pre-fabricated single-crystal ceramic particles, and that during the manufacturing process of the multi-phase fluorescent ceramics, a chemical reaction occurs between the ceramic raw materials to further generate the luminescent phase, allowing pores to form between the luminescent crystal grains in the luminescent phase. Based on this, the following examples are proposed.

[0013] Referring to FIG. 1, FIG. 1 is a structural schematic diagram of the multiphase fluorescent ceramic according to the present invention.

[0014] As shown in Figure 1, the multi-phase fluorescent ceramic 100 includes a luminescent phase (not shown), a matrix phase (not shown), and pores 130. Here, the luminescent phase includes a plurality of luminescent crystal grains 120 bonded to one another. The matrix phase includes a plurality of matrix crystal grains 110 bonded to one another, and the matrix phase and the luminescent phase are interdigitated and distributed in the multi-phase fluorescent ceramic. The pores 130 are at least partially distributed within the luminescent phase, at least partially distributed within the matrix phase, and at least partially distributed between the luminescent phase and the matrix phase.

[0015] As shown in FIG. 1, pores 130 can be distributed among the luminescent grains 120 within the luminescent phase.

[0016] As shown in FIG. 1, the luminescent phase (shown as the gray area in FIG. 1) and the matrix phase (shown as the white area in FIG. 1) are obtained by a solid-state reaction, and therefore do not have a defined shape and are similar to an amorphous state. Here, "distributed in an intricate manner" may mean that the boundaries of the luminescent phase and the matrix phase are intertwined with each other. As shown in FIG. 1, one of the boundaries of the luminescent phase and the matrix phase surrounds and forms a recessed region, and the other of the boundaries of the luminescent phase and the matrix phase surrounds and forms a recessed region, which is located within the recessed region, and the boundaries of the recessed region and the recessed region are bonded to each other.

[0017] Compared to multi-phase fluorescent ceramics in the prior art, for example, multi-phase fluorescent ceramics manufactured by mixing commercially available phosphor powder particles, ceramic particles, and a pore-forming agent and sintering the mixture, the pores are distributed between the phosphor powder particles and the ceramic particles and between the ceramic particles. In contrast, the pores 130 in the multi-phase fluorescent ceramic of the present application are at least partially distributed within the luminescent phase, at least partially distributed within the matrix phase, and at least partially distributed between the luminescent phase and the matrix phase. Therefore, the pores distributed within the luminescent phase can improve the scattering performance of the multi-phase fluorescent ceramic.

[0018] Here, compared to conventional multi-phase fluorescent ceramics, the multi-phase fluorescent ceramic 100 of the present application has good scattering performance, which reduces the diffusion distance of the fluorescent spot and suppresses the diffusion of the light spot, thereby improving the light output efficiency from the front, and thereby achieving high light extraction efficiency.

[0019] In one embodiment, as shown in FIG. 1 , the pores 130 may be uniformly distributed in the multi-phase fluorescent ceramic. The pores 130 distributed in the luminescent phase are referred to as first pores 132. The first pores 132 may be located between the luminescent grains 120, for example, between adjacent luminescent grains 120 that are bonded to each other among the luminescent grains 120. The pores 130 distributed in the matrix phase are referred to as second pores 131. The second pores 131 may be located between the matrix grains 110, for example, between adjacent matrix grains 110 that are bonded to each other among the matrix grains 110. The pores 130 distributed between the luminescent phase and the matrix phase are referred to as third pores 133. The third pores 133 may be located between the luminescent grains 120 and the matrix grains 110 that are bonded to each other among the luminescent grains 120. Each of the luminescent grains 120 and the matrix grains 130 can be regarded as a single crystal particle. Furthermore, some of the pores 130 may be distributed inside the light-emitting crystal grains 120, or may be distributed inside the matrix crystal grains 130.

[0020] 1, the volume ratio of the total volume of the pores 130 to the volume of the multi-phase fluorescent ceramic 100 is less than 5% and greater than 0.1% (e.g., 4%, 3%, 1%, 0.5%). If the content of the pores 130 is too low, the light scattering effect will be weak, but if the content is too high, it may be detrimental to the thermal conductivity of the entire multi-phase fluorescent ceramic 100. Therefore, by maintaining the content of the pores 130 within the above range, the multi-phase fluorescent ceramic 100 can achieve good scattering while ensuring high thermal conductivity.

[0021] In one embodiment, the volume ratio of the total volume of the luminescent phase to the volume of the multi-phase fluorescent ceramic 100 is 10% to 90% (e.g., 10%, 30%, 50%, 60%, 68%, 70%, 80%, 90%). Depending on the volume ratio of the total volume of the luminescent phase to the volume of the multi-phase fluorescent ceramic 100, the luminescent phase can exhibit different distribution conditions in the multi-phase fluorescent ceramic 100.

[0022] Here, in one embodiment (not shown), the luminescent phase exhibits a dispersed particle-like distribution in the multi-phase fluorescent ceramic, and the matrix phase is distributed among the dispersed luminescent phases. Here, in another embodiment (not shown), the luminescent phase exhibits a network-continuous distribution in the multi-phase fluorescent ceramic, and the matrix phase is distributed in a network surrounded by the network-continuous luminescent phase. In still another embodiment (not shown), the luminescent phase exhibits a mixed state of dispersed particle-like distribution and network-continuous distribution in the multi-phase fluorescent ceramic, i.e., the luminescent phase in some regions exhibits a dispersed particle-like distribution and the luminescent phase in some regions exhibits a network-continuous distribution. Of course, in other embodiments, the luminescent phase and the matrix phase may exhibit other distribution forms.

[0023] In one embodiment, as shown in FIG. 1 , the grain size of the light-emitting crystal grains 120 in the multi-phase fluorescent ceramic 100 is 1 μm to 10 μm (e.g., 1 μm, 2 μm, 3 μm, 5 μm, 7 μm, 8 μm, 9 μm, 10 μm). In one embodiment, the grain size of the light-emitting crystal grains 120 that account for 60% to 95% (e.g., 60%, 70%, 80%, 85%, 90%, 95%) of the total number in the multi-phase fluorescent ceramic 100 is 1 μm to 10 μm (e.g., 1 μm, 2 μm, 3 μm, 5 μm, 7 μm, 8 μm, 9 μm, 10 μm). Furthermore, the grain size of the light-emitting crystal grains 120 that account for 60% to 95% or more of the total number in the multi-phase fluorescent ceramic 100 is 2 μm to 5 μm (e.g., 2 μm, 3 μm, 5 μm). In the present application, the size of the luminescent crystal grains 120 is smaller than that of the fluorescent powder used in existing multi-phase fluorescent ceramics, so the number of luminescent crystal grains 120 as luminescent centers is greater, the dispersion is better, which is more advantageous for the uniformity of the luminescent color, and the limitation of the light spot diffusion is also better.

[0024] In the present application, the type of luminescent phase is not particularly limited, and an appropriate luminescent phase can be selected according to actual needs. In one embodiment, the luminescent phase is a garnet luminescent phase (e.g., YAG luminescent phase, LuAG luminescent phase). The rare earth element doped into the luminescent crystal grains 120 is, for example, one or more lanthanides, such as one or more of cerium (chemical symbol: Ce) and europium (chemical symbol: Eu).

[0025] In the present application, the type of matrix phase is not particularly limited, and an appropriate matrix phase can be selected according to actual needs. In one embodiment, the matrix phase is one or more of alumina matrix phase, aluminum nitride matrix phase, magnesia matrix phase, zinc oxide matrix phase, yttria matrix phase, magnesia-alumina spinel matrix phase, yttrium-aluminum garnet matrix phase, etc.

[0026] In one embodiment, the grain size of the matrix crystal grains 110 in the multi-phase fluorescent ceramic 100 is 1 μm to 10 μm (e.g., 1 μm, 2 μm, 3 μm, 5 μm, 7 μm, 8 μm, 9 μm, 10 μm). Furthermore, in one embodiment, the grain size of the matrix crystal grains 110 that account for 60% to 95% (e.g., 60%, 70%, 80%, 85%, 90%, 95%) of the total number of the matrix crystal grains 110 in the multi-phase fluorescent ceramic 100 is 1 μm to 10 μm (e.g., 2 μm, 3 μm, 5 μm, 7 μm, 8 μm, 9 μm, 10 μm). Furthermore, in one embodiment, the grain size of the matrix crystal grains 110 that account for 60% to 95% (e.g., 2 μm, 3 μm, 5 μm) of the total number of the matrix crystal grains 110 in the multi-phase fluorescent ceramic 100 is 2 μm to 5 μm (e.g., 2 μm, 3 μm, 5 μm). The size of the matrix crystal grains 110 in the present application is smaller than that of the matrix crystal grains used in existing multi-phase fluorescent ceramics, so the number of matrix crystal grains 110 in the present application is greater, which corresponds to a greater number of scattering centers, which is beneficial for increasing scattering performance, improving the uniformity of luminescent color, and better limiting light spot diffusion.

[0027] Hereinafter, the present application provides a method for manufacturing the multi-phase fluorescent ceramic 100 according to any one of the above embodiments.

[0028] Referring to FIG. 2, FIG. 2 is a flowchart of a first embodiment of a method for manufacturing a multi-phase fluorescent ceramic according to the present invention.

[0029] As shown in FIG. 2, the method for producing the multi-phase fluorescent ceramic of the present invention may include the following steps S110 to S140.

[0030] In step S110, the ceramic raw materials are mixed to form a mixed powder.

[0031] Here, the ceramic raw materials include matrix phase raw material powder, luminescent phase raw material powder, and a pore-forming agent. The matrix phase raw material powder and the luminescent phase raw material powder are selected according to the types of the matrix phase and the luminescent phase, and are not particularly limited. In step S110, all of the matrix phase raw material powder, the luminescent phase raw material powder, and the pore-forming agent can be directly mixed by an appropriate mixing means (e.g., ball milling) to form a mixed powder.

[0032] In another embodiment, the luminescent phase is a lanthanide-doped garnet luminescent phase, and the matrix phase is an alumina matrix phase, whereby the matrix phase raw material powder includes a first alumina powder, and the luminescent phase raw material powder includes a second alumina powder, yttria powder, and a lanthanide oxide powder.

[0033] In another embodiment, the mass ratio of the sum of the first alumina powder and the second alumina powder to the yttria powder is 1:1 to 6:1 (e.g., 1:1, 1.5:1, 5:3, 2:1, 2.5:1, 6:1), and / or 1.5:1 to 3:1 (e.g., 1.5:1, 5:3, 2.5:1, 3:1).

[0034] In other embodiments, the mass of the lanthanide oxide powder is 0.1% to 2% (e.g., 0.1%, 0.3%, 0.4%, 2%) of the mass of the yttria powder. Furthermore, the mass of the lanthanide oxide powder is 0.3% to 1% (e.g., 0.3%, 0.4%, 1%) of the mass of the yttria powder.

[0035] In another embodiment, the mass of the pore-forming agent is 4% to 20% (for example, 4%, 8%, 10%, 20%) of the total mass of the matrix phase raw material powder and the luminescent phase raw material powder.

[0036] The type of pore-forming agent is not particularly limited, and may be, for example, one or more of PMMA (polymethyl methacrylate, abbreviated as PMMA) microspheres, PS (polystyrene, abbreviated as PS) microspheres, or starch.

[0037] In step S120, the mixed powder is compacted to form a green body.

[0038] In one exemplary embodiment of step S120, the mixed powder may be placed into a mold and dry-pressed to bind the mixed powder and form a shape corresponding to the mold. It can be appreciated that the shape of the green body will depend on the size and shape of the mold, and corresponding adjustments can be made as needed. Of course, other molding methods, such as semi-dry pressing, plastic molding, slip casting, or isostatic pressing, can also be used as needed. Furthermore, appropriate additives can be added to the mixed powder during the molding process to assist in molding.

[0039] In step S130, the green body is heat treated to remove the pore-forming agent.

[0040] In step S130, the green body is heat-treated to decompose the pore-forming agent in the green body. In another embodiment, the green body is heat-treated at a pore-forming agent decomposition temperature of 400°C to 1000°C (e.g., 400°C, 500°C, 654°C, 700°C, 837°C, or 1000°C) for 0.5 to 6 hours (e.g., 0.5 hours, 1 hour, 2.4 hours, 3 hours, 5 hours, or 6 hours) to decompose the pore-forming agent. As can be seen, during the heat treatment at the pore-forming agent decomposition temperature, the pore-forming agent volatilizes in a high-temperature environment, and pores are formed in the corresponding positions in the green body after the pore-forming agent decomposes. Additionally, a binder removal process can be performed simultaneously during the heat treatment process.

[0041] In one exemplary embodiment of step S130, the green body may be placed in a muffle furnace for heat treatment, although of course other suitable heat treatment equipment may be used.

[0042] In step S140, the heat-treated green body is sintered to form a multi-phase fluorescent ceramic.

[0043] In step S140, the heat-treated green body is further sintered to form a multi-phase fluorescent ceramic including a luminescent phase, a matrix phase, and pores in the green body. Here, the luminescent phase includes a plurality of luminescent crystal grains bonded to each other. The matrix phase includes a plurality of matrix crystal grains bonded to each other, and the matrix phase and the luminescent phase are interdigitated in the multi-phase fluorescent ceramic. The pores are at least partially distributed within the luminescent phase, at least partially distributed within the matrix phase, and at least partially distributed between the luminescent phase and the matrix phase.

[0044] Specifically, during the sintering process of step 140, the luminescent phase raw material powder in the green body generates a luminescent phase, which includes a plurality of luminescent crystal grains bound together, and the matrix phase raw material powder in the green body forms a matrix phase, which includes a plurality of matrix crystal grains bound together, and the pores in the green body are further reduced.

[0045] The apparatus used for sintering is not particularly limited, and may be, for example, a vacuum sintering furnace, a hot press sintering furnace, or an SPS (Spark Plasma Sintering, ie, electric plasma sintering, abbreviated as SPS) sintering furnace.

[0046] In another embodiment, the heat-treated green body can be sintered at a sintering temperature of 1400°C to 1700°C (e.g., 1400°C, 1450°C, 1500°C, 1548°C, 1630°C, or 1700°C) for 0.1 to 6 hours (e.g., 0.1 hour, 0.5 hour, 1 hour, 2 hours, 3.4 hours, 4.6 hours, 5 hours, or 6 hours) to form a multi-phase fluorescent ceramic sintered body. Furthermore, the multi-phase fluorescent ceramic sintered body can be annealed in an air atmosphere to form a multi-phase fluorescent ceramic.

[0047] Optionally, based on the first embodiment of the method for manufacturing the multi-phase fluorescent ceramic, a second embodiment of the method for manufacturing the multi-phase fluorescent ceramic is further proposed.

[0048] Before step S140, the method further includes a step of increasing the temperature from the decomposition temperature of the pore-forming agent to a pre-sintering temperature of 1000°C to 1600°C (e.g., 1000°C, 1150°C, 1200°C, 1300°C, 1360°C, 1430°C, 1540°C, 1600°C), and pre-sintering the green body at the pre-sintering temperature for 0.5 hours to 4 hours (e.g., 0.5 hours, 0.7 hours, 1 hour, 1.6 hours, 2.5 hours, 3 hours, 3.6 hours, 4.3 hours, 5 hours, 6 hours) to form a ceramic intermediate.

[0049] Further, based on the above embodiment, step S140 may be The method includes sintering the ceramic intermediate at a sintering temperature of 1400°C to 1700°C for 0.1 to 6 hours to form a multi-phase fluorescent ceramic sintered body, and annealing the multi-phase fluorescent ceramic sintered body in an air atmosphere to form a multi-phase fluorescent ceramic.

[0050] In another embodiment, the method further includes a step of machining the outer shape of the ceramic intermediate body before sintering the ceramic intermediate body. The outer shape of the ceramic intermediate body may be machined according to the required outer shape of the product.

[0051] Based on the first or second embodiment of the method for manufacturing a multi-phase fluorescent ceramic, a third embodiment of the method for manufacturing a multi-phase fluorescent ceramic is further proposed, in which step S110 includes: The method includes mixing luminescent phase raw material powders to prepare a pre-powder, sintering the pre-powder at a precursor sintering temperature of 1000°C to 1600°C (e.g., 1000°C, 1150°C, 1200°C, 1300°C, 1360°C, 1430°C, 1540°C, 1600°C) for 0.5 to 4 hours (e.g., 0.5 hours, 0.7 hours, 1 hour, 1.6 hours, 2.5 hours, 3 hours, 3.6 hours, 4.3 hours, 5 hours, 6 hours) to form a luminescent phase precursor, and mixing the luminescent phase precursor, matrix phase raw material powder, and pore-forming agent to form a mixed powder.

[0052] Specifically, in another embodiment, a luminescent phase precursor powder and suitable auxiliary agents, such as alumina powder, yttria powder, lanthanoid oxide powder, and a binder, are mixed by a first ball milling process to form a mixed slurry. The mixed slurry is then spray-granulated to form a pre-powder. In one embodiment, the binder may be 0.5% to 5% of the total weight of the ceramic raw materials. Furthermore, the sintered luminescent phase precursor may be further processed by ball milling, drying, sieving, etc. The luminescent phase precursor, matrix phase precursor powder, and pore-forming agent may be mixed by a second ball milling process to form a mixed powder, which may then be further processed by drying, sieving, etc.

[0053] Based on the first or second embodiment of the method for manufacturing a multi-phase fluorescent ceramic, a fourth embodiment of the method for manufacturing a multi-phase fluorescent ceramic is further proposed, in which the pore-forming agent includes a first pore-forming agent and a second pore-forming agent, and step S110 comprises: The method includes mixing luminescent phase raw material powder with a first pore-forming agent to form a pre-powder, sintering the pre-powder at a precursor sintering temperature of 1000°C to 1600°C (e.g., 1000°C, 1150°C, 1200°C, 1300°C, 1360°C, 1430°C, 1540°C, 1600°C) for 0.5 to 4 hours (e.g., 0.5 hours, 0.7 hours, 1 hour, 1.6 hours, 2.5 hours, 3 hours, 3.6 hours, 4.3 hours, 5 hours, or 6 hours) to form a luminescent phase precursor, and mixing the luminescent phase precursor, matrix phase raw material powder, and a second pore-forming agent to form a mixed powder.

[0054] Specifically, in another embodiment, a luminescent phase precursor powder, a first pore-forming agent, and a suitable auxiliary agent, such as a second alumina powder, yttria powder, a lanthanoid-based element oxide powder, the first pore-forming agent, and a binder, are mixed by a first ball milling process to form a mixed slurry. The mixed slurry is then spray-granulated to form a pre-powder. In one embodiment, the binder may be 0.5% to 5% by weight of the total ceramic raw materials. Furthermore, the sintered luminescent phase precursor may be further processed by ball milling, drying, sieving, etc. The luminescent phase precursor, matrix phase precursor powder, and second pore-forming agent may be mixed by a second ball milling process to form a mixed powder. The mixed powder may be further processed by drying, sieving, etc.

[0055] Furthermore, in one embodiment, the mass ratio of the first pore-forming agent to the second pore-forming agent may be 0.1 to 10 (for example, 0.1, 1, 2, 3, 6, 10).

[0056] The method for producing the multi-phase fluorescent ceramic of the present invention will be further described below with reference to specific examples. [Example]

[0057] In Example 1, a YAG:Ce luminescent phase is obtained by a solid-state reaction, and pores are formed by PMMA microspheres to obtain a multi-phase fluorescent ceramic with a porous structure. The manufacturing flow is as follows:

[0058] The ceramic raw materials are mixed by ball milling.

[0059] Here, the ceramic raw materials include matrix phase raw material powder, luminescent phase raw material powder and PMMA microspheres, the matrix phase raw material powder includes a first nano-alumina powder, and the luminescent phase raw material powder includes a second nano-alumina powder, nano-yttria powder and nano-cerium oxide powder.

[0060] Here, the mass ratio of the sum of the first nano-alumina powder and the second nano-alumina powder to the nano-yttria powder is 2.5:1, the mass of the nano-cerium oxide powder is 0.3% of the mass of the nano-yttria powder, and the mass of the PMMA microspheres is 8% of the sum of the mass of the matrix phase raw material powder and the luminescent phase raw material powder. The second nano-alumina powder, the nano-yttria powder, and the nano-cerium oxide powder are each weighed out in a stoichiometric ratio.

[0061] The green body is manufactured by placing the mixed powder in a mold and dry pressing the mixed powder to form the green body.

[0062] The green body is placed in a muffle furnace and heat-treated for 4 hours at the decomposition temperature of the pore-forming agent, which is increased from room temperature to 700°C, to decompose the PMMA microspheres.

[0063] The heat treatment temperature of the green body in the muffle furnace is raised from the decomposition temperature of the pore-forming agent to 1200°C, and the green body is sintered at this pre-sintering temperature for 2 hours while maintaining the temperature to form a ceramic intermediate.

[0064] The muffle furnace is switched to a vacuum sintering furnace, and the ceramic intermediate is sintered at a sintering temperature of 1600°C for 3 hours while maintaining the temperature, to form a multiphase fluorescent ceramic sintered body.

[0065] The multi-phase fluorescent ceramic sintered body is annealed in an air atmosphere to form a multi-phase fluorescent ceramic. [Example]

[0066] In Example 2, the matrix phase raw material powder includes a first nano-alumina powder, the luminescent phase raw material powder includes a second nano-alumina powder, nano-yttria powder, and nano-cerium oxide powder, and a YAG:Ce luminescent phase is obtained by a solid-state reaction, and the pores are formed by PS microspheres, thereby obtaining a multi-phase fluorescent ceramic with a porous structure. The manufacturing flow is as follows:

[0067] The mixed powder is produced by ball milling and mixing the first nano-alumina powder, the second nano-alumina powder, the nano-yttria powder, the nano-cerium oxide powder, and the PS microspheres to form the mixed powder.

[0068] Here, the mass ratio of the sum of the first nano-alumina powder and the second nano-alumina powder to the nano-yttria powder is 2:1, the mass of the nano-cerium oxide powder is 0.4% of the mass of the nano-yttria powder, and the mass of the PS microspheres is 10% of the sum of the masses of the matrix phase raw material powder and the luminescent phase raw material powder. The second nano-alumina powder, the nano-yttria powder, and the nano-cerium oxide powder are each weighed out in a stoichiometric ratio.

[0069] The green body is manufactured by placing the mixed powder in a mold and dry pressing the mixed powder to form the green body.

[0070] The green body is placed in a muffle furnace and heat-treated for 4 hours at the decomposition temperature of the pore-forming agent, which is increased from room temperature to 600°C, to decompose the PS microspheres.

[0071] The heat treatment temperature of the green body in the muffle furnace is raised from the decomposition temperature of the pore-forming agent to 1300°C, and the green body is sintered at this pre-sintering temperature for 1 hour while maintaining the temperature, to form a ceramic intermediate body.

[0072] The ceramic intermediate is processed to its external dimensions.

[0073] After the outer dimensions have been processed, the ceramic intermediate is placed in a graphite mold and sintered in an SPS sintering furnace at a sintering temperature of 1500°C for 30 minutes while maintaining the temperature, to form a multi-phase fluorescent ceramic sintered body.

[0074] The multi-phase fluorescent ceramic sintered body is annealed in an air atmosphere to form a multi-phase fluorescent ceramic. [Example]

[0075] In Example 3, the matrix phase raw material powder includes a first nano-alumina powder, the luminescent phase raw material powder includes a second nano-alumina powder, a nano-yttria powder, and a nano-cerium oxide powder, and a YAG:Ce luminescent phase is obtained by a solid-state reaction. Holes are formed by starch, and a multi-phase fluorescent ceramic with a porous structure is obtained. The starch includes a first starch, and the production flow is as follows:

[0076] The mixed slurry is produced by first ball milling the first nano-alumina powder, the nano-yttria powder, the nano-cerium oxide powder, and the binder to form the mixed slurry.

[0077] Here, the mass ratio of the sum of the first nano-alumina powder and the second nano-alumina powder to the nano-yttria powder is 1:1, the mass of the nano-cerium oxide powder is 0.4% of the mass of the nano-yttria powder, and the mass of the first starch is 12% of the sum of the masses of the matrix phase raw material powder and the luminescent phase raw material powder. The second nano-alumina powder, the nano-yttria powder, and the nano-cerium oxide powder are each weighed out in a stoichiometric ratio.

[0078] The pre-powder is produced by spray granulating the mixed slurry into the pre-powder.

[0079] The YAG:Ce precursor was prepared by sintering the pre-powder at a precursor sintering temperature of 1300°C for 3 hours while maintaining the temperature, to form the YAG:Ce precursor.

[0080] The YAG:Ce precursor is subjected to a third ball milling, and the YAG:Ce precursor after the third ball milling is sieved to obtain a YAG:Ce precursor having a predetermined size.

[0081] The mixed powder is produced by subjecting the sieved YAG:Ce precursor, the second nano-alumina powder, and the first starch to a second ball milling mixing to form the mixed powder.

[0082] The mixed powder is dried, and the dried mixed powder is sieved.

[0083] The green body is produced by dry pressing the sieved mixed powder in a mold to form a green body.

[0084] The green body is placed in a muffle furnace and heat-treated for 4 hours at the decomposition temperature of the pore-forming agent, which is increased from room temperature to 650°C, to decompose the starch.

[0085] The heat treatment temperature of the green body in the muffle furnace is raised from the decomposition temperature of the pore-forming agent to 1400°C, and the green body is sintered at this pre-sintering temperature for 2 hours while maintaining the temperature to form a ceramic intermediate.

[0086] The muffle furnace is switched to a vacuum sintering furnace, and the ceramic intermediate is sintered at a sintering temperature of 1600°C for 4 hours while maintaining the temperature, to form a multiphase fluorescent ceramic sintered body.

[0087] The multi-phase fluorescent ceramic is annealed in an air atmosphere to form a multi-phase fluorescent ceramic. [Example]

[0088] In Example 4, the matrix phase raw material powder includes a first nano-alumina powder, the luminescent phase raw material powder includes a second nano-alumina powder, a nano-yttria powder, and a nano-cerium oxide powder, and a YAG:Ce luminescent phase is obtained by a solid-state reaction, and pores are formed by starch to obtain a multi-phase fluorescent ceramic with a porous structure. Here, the starch includes a first starch and a second starch, and the production flow is as follows:

[0089] The mixed slurry is produced by first ball milling the second nano-alumina powder, the nano-yttria powder, the nano-cerium oxide powder, the binder, and the second starch to form the mixed slurry.

[0090] Here, the mass ratio of the sum of the first nano-alumina powder and the second nano-alumina powder to the nano-yttria powder is 5:1, the mass of the nano-cerium oxide powder is 0.4% of the mass of the nano-yttria powder, the sum of the mass of the first starch and the second starch is 20% of the sum of the mass of the matrix phase raw material powder and the luminescent phase raw material powder, and the mass ratio of the first starch to the second starch is 1.25. The second nano-alumina powder, the nano-yttria powder, and the nano-cerium oxide powder are each weighed out in a stoichiometric ratio.

[0091] The pre-powder is produced by spray granulating the mixed slurry into the pre-powder.

[0092] The YAG:Ce precursor was prepared by sintering the pre-powder at a precursor sintering temperature of 1300°C for 3 hours while maintaining the temperature, to form the YAG:Ce precursor.

[0093] The YAG:Ce precursor is subjected to a third ball milling, and the YAG:Ce precursor after the third ball milling is sieved to obtain a YAG:Ce precursor having a predetermined size.

[0094] The mixed powder is produced by subjecting the sieved YAG:Ce precursor, the second nano-alumina powder, and the first starch to a second ball milling mixing to form the mixed powder.

[0095] The mixed powder is dried, and the dried mixed powder is sieved.

[0096] The green body is produced by dry pressing the sieved mixed powder in a mold to form a green body.

[0097] The green body is placed in a muffle furnace and heat-treated for 4 hours at the decomposition temperature of the pore-forming agent, which is increased from room temperature to 650°C, to decompose the starch.

[0098] The heat treatment temperature of the green body in the muffle furnace is raised from the decomposition temperature of the pore-forming agent to 1400°C, and the green body is sintered at this pre-sintering temperature for 2 hours while maintaining the temperature to form a ceramic intermediate.

[0099] The muffle furnace is switched to a vacuum sintering furnace, and the ceramic intermediate is sintered at a sintering temperature of 1600°C for 4 hours while maintaining the temperature, to form a multiphase fluorescent ceramic sintered body.

[0100] The multi-phase fluorescent ceramic is annealed in an air atmosphere to form a multi-phase fluorescent ceramic.

[0101] Referring to FIG. 3, FIG. 3 is a structural schematic diagram of a light emitting device according to the present application.

[0102] 3, the light-emitting device 300 includes an excitation light source 200 and a multi-phase fluorescent ceramic 100 according to the above-described embodiment of the multi-phase fluorescent ceramic. The laser light source 200 is used to output excitation light to the multi-phase fluorescent ceramic 100 so as to excite the multi-phase fluorescent ceramic 100 to generate fluorescence. Here, the light-emitting device 300 may include a projection device or an illumination device. The excitation light source 200 may include, for example, a solid-state light source such as an LED and / or a laser.

[0103] The above are only embodiments of the present application and do not limit the scope of the patent of the present application. Any equivalent structure or equivalent flow transformation made using the contents of the specification and drawings of the present application, or any direct or indirect application to other related technical fields, are also included in the scope of patent protection of the present application.

Claims

1. A multi-phase fluorescent ceramic, comprising a luminescent phase, a matrix phase, and pores; the luminescent phase includes a plurality of luminescent crystal grains bonded together, the matrix phase includes a plurality of matrix crystal grains bonded to each other, and the matrix phase and the luminescent phase are interdigitated and distributed in the multi-phase fluorescent ceramic; the pores are at least partially distributed within the luminescent phase, at least partially distributed within the matrix phase, and at least partially distributed between the luminescent phase and the matrix phase; the luminescent phase exhibits a network-like continuous distribution in the multi-phase fluorescent ceramic, and the matrix phase is distributed in a network surrounded by the network-like continuous distribution of the luminescent phase; Alternatively, the luminescent phase exhibits a mixed state of dispersed particulate distribution and network-like continuous distribution in the multi-phase fluorescent ceramic.

2. The multi-phase fluorescent ceramic according to claim 1, characterized in that the volume ratio of the total volume of the pores to the volume of the multi-phase fluorescent ceramic is less than 5% and more than 0.1%, and / or the volume ratio of the total volume of the luminescent phase to the volume of the multi-phase fluorescent ceramic is 10% to 90%.

3. The multi-phase fluorescent ceramic according to claim 1 or 2, characterized in that the grain size of the luminescent crystal grains that account for 60% to 95% of the total number in the multi-phase fluorescent ceramic is 1 μm to 10 μm, and / or the grain size of the matrix crystal grains that account for 60% to 95% of the total number in the multi-phase fluorescent ceramic is 1 μm to 10 μm.

4. 3. The multi-phase fluorescent ceramic according to claim 1, wherein the luminescent phase is a lanthanide-doped garnet luminescent phase, and the matrix phase is an alumina matrix phase.

5. A method for producing the multi-phase fluorescent ceramic according to claim 1 or 2, comprising: mixing a matrix phase material powder, a luminescent phase material powder, and ceramic raw materials including a pore-forming agent to form a mixed powder; compacting the mixed powder to form a green body; heat treating the green body to remove the pore-forming agent; and sintering the heat-treated green body to form the multi-phase fluorescent ceramic. The pore-forming agent includes a first pore-forming agent and a second pore-forming agent, and the step of mixing the ceramic raw materials includes: mixing the luminescent phase raw material powder and the first pore-forming agent to prepare a pre-powder; sintering the pre-powder at a precursor sintering temperature of 1000°C to 1600°C for 0.5 hours to 4 hours to form a luminescent phase precursor; and mixing the luminescent phase precursor, the matrix phase raw material powder, and the second pore-forming agent to form the mixed powder.

6. 6. The method for producing a multi-phase fluorescent ceramic according to claim 5, wherein the mass of the pore-forming agent is 4% to 20% of the sum of the masses of the matrix phase raw material powder and the luminescent phase raw material powder.

7. 6. The manufacturing method according to claim 5, wherein the matrix phase raw material powder includes a first alumina powder, the luminescent phase raw material powder includes a second alumina powder, an yttria powder, and a lanthanoid oxide powder, a mass ratio of the sum of the masses of the first alumina powder and the second alumina powder to the yttria powder is 1:1 to 6:1, and a mass of the lanthanoid oxide powder is 0.1% to 2% of a mass of the yttria powder.

8. The step of heat treating the green body to remove the pore-forming agent comprises:

6. The method of claim 5, further comprising heat treating the green body at a pore-forming agent decomposition temperature of 400° C. to 1000° C. for 0.5 to 6 hours to decompose the pore-forming agent.

9. Prior to the step of sintering the heat-treated green body to form the multi-phase fluorescent ceramic, the manufacturing method further comprises:

9. The method of claim 8, further comprising the steps of: increasing the temperature from the decomposition temperature of the pore-forming agent to a pre-sintering temperature of 1000°C to 1600°C; and pre-sintering the green body at the pre-sintering temperature for 0.5 hours to 4 hours to form a ceramic intermediate.

10. sintering the heat-treated green body to form the multi-phase fluorescent ceramic; Sintering the ceramic intermediate body at a sintering temperature of 1400°C to 1700°C for 0.1 hours to 6 hours to form a multi-phase fluorescent ceramic sintered body; 10. The method according to claim 9, further comprising annealing the multi-phase fluorescent ceramic sintered body in an air atmosphere to form the multi-phase fluorescent ceramic.

11. 6. The method of claim 5, wherein the pore-forming agent is one or more of PMMA microspheres, PS microspheres, and starch.

12. A light emitting device comprising: an excitation light source; and the multi-phase fluorescent ceramic according to claim 1 or 2.

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