Ceramic powder, ceramic product, method for manufacturing the same, and electronic device

Abstract

This invention relates to the field of ceramic materials technology, and in particular to ceramic powders, ceramic products, their preparation methods, and electronic devices. The ceramic powder comprises a main component and a plasticizing agent added to the main component; the main component includes zirconium oxide; the plasticizing agent comprises at least two components selected from amorphous SiO2 particles, glass powder, and rare earth oxides. The ceramic powder of this invention, based on the main component, incorporates a plasticizing agent. After adding the plasticizing agent, the ceramic powder becomes suitable for hot bending forming, solving the problem of difficult machining of ceramic shells.

Description

Technical Field

[0001] This invention relates to the field of ceramic materials technology, and in particular to ceramic powders, ceramic products, their preparation methods, and electronic devices. Background Technology

[0002] Zirconia ceramics possess high hardness, high strength, and a smooth, jade-like texture, making them a popular choice for high-end electronic product casings. However, due to their high hardness and brittleness, traditional zirconia ceramics are difficult to machine into 2.5D or 3D casings, resulting in low yields and high costs, which limits the large-scale application of ceramic casings. Summary of the Invention

[0003] Based on this, the present invention provides a ceramic powder, a ceramic product, a method for preparing the same, and an electronic device to solve the problem of difficult machining of traditional zirconia ceramic shells.

[0004] The first aspect of this invention provides a ceramic powder, the technical solution of which is as follows:

[0005] A ceramic powder comprising a main component and a plasticizing agent added to the main component;

[0006] The main component includes zirconium oxide;

[0007] The plasticizing agent comprises at least two components selected from amorphous SiO2 particles, glass powder, and rare earth oxides.

[0008] A second aspect of the present invention provides a ceramic product made from raw materials including the ceramic powder described above.

[0009] A third aspect of this invention provides a method for preparing a ceramic product. The technical solution is as follows:

[0010] A method for preparing a ceramic product includes the following steps:

[0011] The above-mentioned ceramic powder is used to prepare ceramic green bodies;

[0012] The ceramic green body is subjected to debinding and sintering treatment to prepare a ceramic plate;

[0013] The ceramic plate is then prepared into a ceramic product.

[0014] A fourth aspect of this invention provides an electronic device. The technical solution is as follows:

[0015] An electronic device includes a display screen, a motherboard, and the aforementioned ceramic product;

[0016] The display screen is connected to the ceramic product, and a space is defined between the display screen and the ceramic product.

[0017] The motherboard is located within the accommodating space and is electrically connected to the display screen.

[0018] Compared with traditional solutions, the present invention has the following advantages:

[0019] The ceramic powder of the present invention incorporates a plasticizing agent on the basis of the main components. After the addition of the plasticizing agent, the ceramic powder can be used for hot bending molding, thus solving the problem of difficult machining of ceramic shells. Attached Figure Description

[0020] Figure 1 Optical micrographs of the pore defects in Examples 1, 2, 3, and Comparative Examples 3, 4, and 5;

[0021] Figure 2 Optical micrographs of the cavity defects in Examples 4 and 5, and Comparative Examples 7 and 8;

[0022] Figure 3 Optical micrographs of the pore defects in Examples 6, 7, 8, 9, and 10 are shown. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to specific embodiments. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0025] In this invention, the terms "first aspect," "second aspect," "third aspect," and "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," and "fourth," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0026] In this invention, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions that include the listed features.

[0027] In this invention, % (w / w) and wt% both represent weight percentage, % (v / v) refers to volume percentage, and % (w / v) refers to mass-volume percentage.

[0028] Traditional zirconia ceramics can be prepared into ceramic green bodies through molding methods such as dry pressing, injection molding, tape casting, or casting. After debinding and sintering, the ceramic green bodies form ceramic plates. To further prepare 2.5D or 3D shells, extensive machining is required. However, due to the hardness and brittleness of the material, machining is very difficult, resulting in low yield and high shell costs, which limits the large-scale application of the shells.

[0029] One embodiment of the present invention provides a ceramic powder, comprising a main component and a plasticizing agent added to the main component;

[0030] The main component includes zirconium oxide;

[0031] The plasticizing agent includes at least two components from amorphous SiO2 particles, glass powder, and rare earth oxides.

[0032] The ceramic powder of this embodiment has a plasticizing agent added to the main component. After adding the plasticizing agent, the ceramic powder can be used for hot bending molding, which solves the problem of difficult machining of ceramic shells.

[0033] The hot bending forming of ceramic powder used in this embodiment can greatly reduce the amount of machining required for the shell, resulting in a significant cost advantage. Ceramic hot bending forming is similar to glass hot bending forming, both involving applying pressure to a flat plate using hot bending equipment and molds under high temperature conditions to deform it. The difference lies in the fact that glass hot bending forming mainly relies on the softening of the glass, typically at around 800°C, while ceramic hot bending deformation mainly relies on the superplastic deformation of the ceramic at high temperatures, usually requiring temperatures exceeding 1400°C or even higher.

[0034] Considering the high temperatures required for ceramic hot bending deformation, these temperatures pose significant challenges to the cost and lifespan of hot bending equipment and dies, while also consuming substantial energy, contradicting the principles of "carbon peaking" and "carbon neutrality." Furthermore, the inventors discovered that after hot bending deformation, ceramic surfaces are highly susceptible to cavitation, characterized by dense, uniformly oriented, elliptical pores ranging in size from 1 to 100 μm. These pores severely impact the appearance quality of the ceramic shell. Analysis revealed that the primary cause of cavitation is exceeding the plastic deformation limit, leading to ceramic grain detachment and ultimately, visible pores. Through continuous research, the inventors found a solution to these problems. In this embodiment, the amount of plasticizing agent added to the main component and the composition and content of each component within the plasticizing agent are adjusted, enabling ceramic plates prepared from the ceramic powder to be hot-bent into shells at temperatures between 1000°C and 1400°C, with a pore density of less than 100 pores / mm² on the surface of the prepared shell.2 Furthermore, by adjusting the amount of plasticizing agent added to the main component and the composition and content of each component in the plasticizing agent, the ceramic plate prepared from the ceramic powder can be hot-bent into a shell at a temperature of 1000℃~1300℃, and the pore density on the surface of the prepared shell is less than 50 pores / mm². 2 Furthermore, by adjusting the amount of plasticizing agent added to the main component and the composition and content of each component in the plasticizing agent, the ceramic plate prepared from the ceramic powder can be hot-bent into a shell at a temperature of 1000℃~1250℃, and the pore density on the surface of the prepared shell is less than 20 pores / mm². 2 .

[0035] According to research conducted by the inventors, studies have shown that refining the grain size can reduce the deformation temperature of ceramics in the superplastic process. However, this requires a grain size of <0.1μm, which necessitates specialized ceramic powders and processing techniques. Currently, this technology remains only feasible in the laboratory and cannot be industrialized. In this embodiment, however, it is not necessary to refine the grain size of the ceramic plate prepared from the ceramic powder to <0.1μm; superplastic deformation of the ceramic can still be achieved at a lower temperature.

[0036] The concept of superplastic deformation in ceramics was first proposed by scholar Waka and has been the subject of numerous studies in recent decades. Researchers have explored the mechanisms and causes of superplastic deformation in ceramics, but a unified understanding has not yet been reached. The current mainstream view is that grain boundary sliding is an important deformation mechanism.

[0037] Based on current mainstream viewpoints, the inventors analyzed the mechanism of action of the plasticizing agent in this embodiment. Specifically, the amorphous SiO2 particles in the plasticizing agent mainly play the following two roles: 1) During hot bending, they melt into a viscous liquid phase and are distributed at the grain boundaries, which can reduce the grain boundary flow stress, allowing the ceramic to begin superplastic deformation at a lower temperature, thereby reducing the hot bending temperature and suppressing cavitation; 2) They have good bonding force with the zirconia grains in the main component, avoiding the decrease in mechanical strength of the ceramic shell caused by weak grain boundaries. The glass powder mainly plays the following two roles: 1) Similar to the function of amorphous SiO2 particles, it plays the role of reducing the hot bending temperature and suppressing cavitation; 2) Since the viscosity of amorphous SiO2 particles increases after melting, the addition of glass powder can reduce the overall viscosity of the plasticizing agent. When used in combination with amorphous SiO2 particles, it can achieve a synergistic effect of 1+1>2. Rare earth oxides mainly play the following roles: improving the wettability of plasticizers and zirconium oxide grains in the main component, and ensuring that the liquid phase plasticizers uniformly coat the zirconium oxide grains during hot bending, thereby maximizing the function of the plasticizers.

[0038] In summary, the plasticizing agent in this embodiment can exist as a liquid phase with moderate viscosity during hot bending, uniformly distributed at the grain boundaries, and exhibits good wettability and bonding force with zirconia grains. This promotes superplastic deformation of the ceramic, reduces the hot bending temperature, and suppresses cavitation. It also helps maintain the mechanical strength of the ceramic shell.

[0039] Optionally, the amount of plasticizing agent added accounts for 2 wt% to 5 wt% of the main component. Experimental verification has shown that when the amount of plasticizing agent added is less than 2 wt% of the main component, its effect on reducing hot bending temperature and reducing pore density is not significant. When the amount of plasticizing agent added exceeds 5 wt% of the main component, it weakens the grain boundary strength of the ceramic, leading to a decrease in the mechanical strength of the ceramic material.

[0040] In this embodiment, the plasticizing agent includes amorphous SiO2 particles, glass powder, and rare earth oxides.

[0041] Optionally, the particle size D50 of the amorphous SiO2 particles is less than 40 nm. Preferably, the particle size D50 of the amorphous SiO2 particles is less than 20 nm. The amorphous SiO2 particles exist as independent components.

[0042] Optionally, the proportion of amorphous SiO2 particles in the plasticizing agent is 10wt% to 80wt%. Experimental verification shows that when the proportion of amorphous SiO2 particles in the plasticizing agent is less than 10wt%, it easily leads to insufficient bonding strength between the particles and ceramic grains, which is detrimental to the mechanical strength of the ceramic material. When the proportion of amorphous SiO2 particles in the plasticizing agent is greater than 80wt%, it easily leads to excessive viscosity of the plasticizing agent, which is not conducive to reducing the hot bending temperature and reducing the pore density. Preferably, the proportion of amorphous SiO2 particles in the plasticizing agent is 20wt% to 70wt%.

[0043] Optionally, the raw materials for the glass powder include SiO2, and also include at least one of Al2O3, MgO, ZnO, CaO, TiO2, SrO and K2O.

[0044] Optionally, the proportion of SiO2 in the glass powder is 10wt% to 80wt%; the proportion of Al2O3 in the glass powder is no more than 50wt%; the proportion of MgO in the glass powder is no more than 40wt%; the proportion of ZnO in the glass powder is no more than 40wt%; the proportion of CaO in the glass powder is no more than 40wt%; the proportion of TiO2 in the glass powder is no more than 20wt%; the proportion of SrO in the glass powder is no more than 10wt%; and the proportion of K2O in the glass powder is no more than 10wt%.

[0045] For example, glass powder can be a binary compound, a ternary compound, a quaternary compound, or a mixture thereof. Binary compounds can be SiO2-Al2O3, SiO2-MgO, SiO2-ZnO, SiO2-CaO, SiO2-SrO, or a mixture thereof. Ternary compounds can be SiO2-Al2O3-CaO, SiO2-Al2O3-MgO, SiO2-Al2O3-ZnO, SiO2-Al2O3-SrO, SiO2-Al2O3-K2O, SiO2-CaO-K2O, or a mixture thereof. Quaternary compounds can be SiO2-CaO-Al2O3-MgO, SiO2-MnO2-TiO2-MgO, or a mixture thereof. Preferably, the glass powder is SiO2-ZnO, SiO2-CaO, SiO2-Al2O3-ZnO, SiO2-CaO-Al2O3-MgO, or SiO2-MnO2-TiO2-MgO. More preferably, the glass powder is SiO2-ZnO, SiO2-Al2O3-ZnO, or SiO2-MnO2-TiO2-MgO.

[0046] Alternatively, the glass powder can be prepared by melt quenching.

[0047] Specifically, the steps for preparing glass powder by melt quenching include:

[0048] The raw materials for glass powder are mixed evenly, heated and melted into molten glass, then quenched, and then crushed and ground. Optionally, the glass powder is ground until the particle size D50 is less than 1 μm.

[0049] Optionally, the proportion of glass powder in the additives is 5 wt% to 70 wt%. Experimental verification has shown that when the proportion of glass powder in the plasticizing additives is less than 5 wt%, it easily leads to excessive viscosity of the plasticizing additives and high grain slip stress, which is detrimental to reducing hot bending temperature and reducing pore density. When the proportion of glass powder in the plasticizing additives is greater than 70 wt%, it easily leads to low ceramic grain boundary strength and low mechanical strength of the ceramic material. Preferably, the proportion of glass powder in the plasticizing additives is 15 wt% to 60 wt%.

[0050] Optionally, the rare earth oxide includes at least one selected from La2O5, Sm2O3, Nd2O3, Er2O3, Y2O3, and CeO2. Preferably, the rare earth oxide includes at least one selected from La2O5, Sm2O3, and Nd2O3.

[0051] It should be noted that, since Y₂O₃ and CeO₂ are commonly used zirconium oxide stabilizers, when Y₂O₃ or CeO₂ is selected as the rare earth oxide in this embodiment, a large amount added will affect the physical and chemical properties of the ceramic. Therefore, in this embodiment, Y₂O₃ or CeO₂ may not be selected alone as the rare earth oxide, and when both Y₂O₃ and CeO₂ are selected, the total amount of both added shall account for less than 10 wt% of the plasticizing agent.

[0052] Optionally, the proportion of rare earth oxides in the plasticizing agent is 5wt% to 20wt%. Experimental verification shows that when the proportion of rare earth oxides in the plasticizing agent is less than 5wt%, insufficient wettability between the plasticizing agent and the grains is easily achieved, which is detrimental to reducing the hot bending temperature and suppressing cavitation. When the proportion of rare earth oxides in the plasticizing agent is greater than 20wt%, it increases costs and is also detrimental to reducing the hot bending temperature and suppressing cavitation.

[0053] Optionally, the particle size D50 of the rare earth oxides is less than 200 nm. Preferably, the particle size D50 of the rare earth oxides is less than 100 nm.

[0054] By adjusting the amount of plasticizer added to the main component and the composition and content of each component in the plasticizer, this embodiment can reduce the ceramic hot bending temperature by more than 200°C compared to the embodiment without plasticizer, and is expected to increase mold life by more than 50% and save energy by more than 15%. It can also significantly improve cavitation, reducing porosity by up to 90%, while maintaining good mechanical strength of the ceramic material.

[0055] In this embodiment, zirconium oxide accounts for 72wt% to 98wt% of the main component.

[0056] Optionally, the primary particle size of zirconium oxide is D50 ≤ 100 nm. Preferably, the primary particle size of zirconium oxide is D50 ≤ 80 nm.

[0057] In this embodiment, the main component also includes a stabilizer. The stabilizer's function is to ensure that the zirconia ceramic maintains a high content of tetragonal phase at the greenhouse temperature and to ensure that the ceramic has good stability, making it less prone to cracking during sintering and processing.

[0058] Optionally, the stabilizer includes at least one selected from Y₂O₃, CeO₂, MgO, and CaO. Preferably, the stabilizer is Y₂O₃.

[0059] Optionally, the stabilizer accounts for 2 wt% to 20 wt% of the main component. Preferably, the stabilizer accounts for 3 wt% to 6 wt% of the main component.

[0060] In this embodiment, the main component also includes HfO2. HfO2 is a homologous oxide of Zr and a byproduct of ZrO2, and they have similar physicochemical properties. In this embodiment, HfO2 has no significant impact on the hot bending forming of ceramics, and its proportion in the main component is not strictly required. Optionally, the proportion of HfO2 in the main component does not exceed 3 wt%.

[0061] In this embodiment, the main component also includes a colorant. The function of the colorant is to dye the milky white zirconia ceramic to the desired appearance color.

[0062] Optionally, the colorant includes Al2O3, ZnO, CoO, Fe2O3, Cr2O3, NiO, MnO, Er2O3, Nd2O3, and Pr6O. 11 At least one of CuO, TiO2, Nb2O5, CaO, CeO2 and BaO.

[0063] Optionally, the colorant accounts for no more than 5 wt% of the main component.

[0064] One embodiment of the present invention also provides a ceramic product prepared from raw materials including the above-described ceramic powder.

[0065] In this embodiment, the ceramic product is the shell.

[0066] In this embodiment, the shell is prepared by hot bending a ceramic plate, which is made from raw materials including the above-mentioned ceramic powder.

[0067] Furthermore, the shell is prepared by hot bending the aforementioned ceramic plate at a temperature of 1000℃ to 1400℃, and the pore density on the surface of the shell is less than 100 pores / mm². 2 Furthermore, the shell is prepared by hot bending the aforementioned ceramic plate at a temperature of 1000℃ to 1300℃, and the pore density on the surface of the shell is less than 50 pores / mm². 2 Furthermore, the shell is prepared by hot bending the aforementioned ceramic plate at a temperature of 1000℃~1250℃, and the pore density on the surface of the shell is less than 20 pores / mm². 2 .

[0068] One embodiment of the present invention also provides a method for preparing a ceramic product, comprising the following steps:

[0069] The above-mentioned ceramic powder was used to prepare ceramic green bodies;

[0070] The ceramic green body is subjected to debinding and sintering treatment to prepare a ceramic plate;

[0071] The ceramic plate is then prepared into a ceramic product.

[0072] Optionally, depending on the requirements, the above-mentioned ceramic powder can be prepared into ceramic granulation powder, ceramic feed or ceramic slurry, and then prepared into ceramic green body by casting, dry pressing, injection molding or other molding methods.

[0073] In this embodiment, the ceramic green body is debinded at 400℃~600℃ for 24h~48h to fully remove organic matter. The debinded ceramic green body is then sintered at 1000℃~1400℃ for 1h~2h to obtain a ceramic green body with a density ≥99% and an average grain size ≤300nm. The ceramic green body is then double-sided ground to obtain a ceramic plate with a thickness of 0.1mm~1.0mm and a surface roughness Ra less than 0.1μm.

[0074] In this embodiment, the ceramic product is the shell.

[0075] In this embodiment, the method for preparing the ceramic plate into a shell is hot bending. Understandably, placing the ceramic plate into a hot bending mold and then hot bending it in a hot bending device can yield a 2.5D or 3D shell.

[0076] Optionally, the molding temperature is 1000℃~1400℃, and the molding pressure is 10N~200N. Further optionally, the molding temperature is 1000℃~1300℃. Even more optionally, the molding temperature is 1000℃~1250℃.

[0077] Optionally, after hot bending, there is also a finishing step, which includes CNC machining, polishing, laser engraving, sandblasting, coating, etc. After finishing, the final shell product is obtained.

[0078] This embodiment also provides an electronic device, including a display screen, a motherboard, and the aforementioned ceramic product;

[0079] The display screen is connected to the ceramic product, and a space is defined between the display screen and the ceramic product.

[0080] The motherboard is housed within the enclosure and is electrically connected to the display screen.

[0081] The following description is further illustrated with specific embodiments and comparative examples. Unless otherwise specified, the raw materials involved in the following specific embodiments and comparative examples are all commercially available. Unless otherwise specified, the instruments used are all commercially available. Unless otherwise specified, the processes involved are conventionally selected by those skilled in the art.

[0082] Example 1

[0083] This embodiment provides a ceramic powder, a shell, and a method for preparing the same, with the following steps:

[0084] Step 1: Referring to Table 1, prepare 56 wt% SiO2, 21 wt% Al2O3, and 23 wt% ZnO by mass percentage. Mix the three ingredients evenly, heat and melt them into a glass melt, then quench it, and then crush and grind it until the particle size D50 is less than 1 μm to obtain glass powder.

[0085] Step 2: Prepare 30.1 wt% SiO2 (fumed silica, amorphous, with a particle size D50 of 8 nm), 56.1 wt% of the above-mentioned glass powder, and 13.8 wt% rare earth oxides (10.1 wt% La2O5 and 3.7 wt% Sm2O3) by mass percentage, and mix the three together to obtain the molding aid.

[0086] Step 3: Prepare 91 wt% ZrO2, 4.5 wt% Y2O3, 1.5 wt% HfO2, and 3.0 wt% Al2O3 by mass percentage, which will be the main components of the ceramic powder. Prepare 4 wt% of the above-mentioned plasticizing agent as the main components. Mix the main components and plasticizing agent evenly to obtain the ceramic powder.

[0087] Step 4: Prepare ceramic granules from the above ceramic powder, and then dry-press them into ceramic green bodies. Perform a binder removal treatment on the ceramic green bodies at 500℃ for 24 hours, followed by sintering at 1300℃ for 2 hours to prepare ceramic green bodies with a density ≥99%. Grind the ceramic green bodies on both sides to obtain ceramic plates with a thickness of 0.4 mm and a surface roughness Ra less than 0.1 μm. Place the ceramic plates into a hot bending mold, and then place them in a hot bending machine for hot bending. The hot bending temperatures and hot bending bar loads are shown in Table 1, resulting in a 3D ceramic shell.

[0088] Step 5: Inspect the obtained 3D ceramic shell, mainly including four aspects: bending strength, steel ball impact strength, appearance quality (pore density), grain size, and surface profile. The specific test methods are as follows: Test results are shown in Table 1. Among them, when testing pore density, the optical micrograph of the pore defects in Example 1 is shown below. Figure 1 As shown.

[0089] 1) Four-point bending strength was tested in accordance with GB / T 6569-2006 Test Method for Bending Strength of Fine Ceramics. 32 valid data points were collected for each sample. The maximum and minimum values ​​were removed and the average value was calculated.

[0090] 2) Steel ball impact strength, the test method refers to "JC / T 2130-2012 Cover Glass for Video Screens of Mobile Electronic Products", the shell thickness is 0.50mm and the steel ball weight is 32g.

[0091] 3) Pore density: First, observe with the naked eye for dense pores under 1000±200 LUX illumination. Then, use an optical microscope to magnify and observe the locations of dense pores at a magnification of 500x, with a field of view of 0.357 mm². 2 (0.689 × 0.518 mm). At least 10 fields of view were observed for each sample, with a minimum interval of 10 mm between each field of view. The average number of pores, N, was calculated as N / 0.357 mm. 2 This refers to the pore density.

[0092] 4) Grain size: Refer to ISO 13383-1-2012 Microstructure description of fine ceramics (advanced ceramics, high-tech ceramics) - Part 1: Grain size and particle size. After polishing the sample surface, it was subjected to thermal etching at 1100℃ for 30 min, followed by ion sputtering gold plating, and then the grain size was determined by scanning electron microscopy using the linear intercept method.

[0093] 5) Surface profile: Use a profile measuring instrument to test the surface profile of the shell and compare it with the drawing. Mark the maximum surface profile difference. Generally, the surface profile difference between the actual shell and the drawing should be less than 0.2mm.

[0094] Examples 2 and 3, Comparative Examples 1, 2, 3, and 4

[0095] Referring to Table 1 and the preparation method of the shell in Example 1, ceramic powders and shells for Examples 2, 3, and Comparative Examples 1, 2, 3, and 4 were prepared.

[0096] The main difference between Example 2 and Example 1 is that the hot bending temperature is different.

[0097] The main difference between Example 3 and Example 1 is that the content and composition of the plasticizing agent in the ceramic powder are different.

[0098] The main difference between Comparative Example 1 and Example 1 is that no plasticizing agent was added to the ceramic powder.

[0099] The main difference between Comparative Example 2 and Example 2 is that no plasticizer was added to the ceramic powder.

[0100] The main difference between Comparative Example 3 and Example 1 is that no plasticizing agent was added to the ceramic powder, and the hot bending temperature is different.

[0101] The main difference between Comparative Example 4 and Example 1 is that no plasticizing agent was added to the ceramic powder, and the hot bending temperature is different.

[0102] Referring to Example 1, the 3D ceramic shells obtained in Examples 2 and 3, and Comparative Examples 1, 2, 3, and 4 were tested, and the test results are shown in Table 1. Among them, when testing the pore density, the optical micrographs of the pore defects in Examples 2 and 3, and Comparative Examples 3, 4, and 5 are shown below. Figure 1 As shown.

[0103] Table 1

[0104]

[0105]

[0106]

[0107] Table 1 shows that adding plasticizing agents can reduce the hot bending temperature of white zirconia ceramics by 200–250℃, while reducing the pore density by 98% (from 141.5 pores / mm²). 2 Reduced to 1.7 per mm 2 Furthermore, the flexural strength and impact strength of the ceramic material did not change significantly. Figure 1 It can be seen that, compared with comparative examples 3, 4, and 5, examples 1, 2, and 3 have fewer pore defects.

[0108] Example 4

[0109] This embodiment provides a ceramic powder, a shell, and a method for preparing the same, with the following steps:

[0110] Step 1: Referring to Table 2, prepare 50 wt% SiO2, 30 wt% MnO2, 15 wt% TiO2, and 5 wt% MgO by mass percentage. Mix the four ingredients evenly, heat and melt them into a glass melt, then quench it, and then crush and grind it until the particle size D50 is less than 1 μm to obtain glass powder.

[0111] Step 2: Prepare 15wt% SiO2 (fumed silica, amorphous, with a particle size D50 of 12nm), 70wt% of the above-mentioned glass powder, and 15wt% rare earth oxides (9wt% La2O5, 5wt% Y2O3, and 1% Sm2O3) by mass percentage, and mix the three evenly to obtain the molding aid.

[0112] Step 3: Prepare 89.4 wt% ZrO2, 5.6 wt% Y2O3, 1.5 wt% HfO2, and 3.5 wt% 35 wt% CoO-15 wt% ZnO-35 wt% Fe2O3-15 wt% Al2O3 by mass percentage as the main components of the ceramic powder. Prepare 4.5 wt% of the above-mentioned plasticizing agent as the main components. Mix the main components and plasticizing agent evenly to obtain the ceramic powder.

[0113] Step 4: Prepare ceramic granules from the above ceramic powder, and then dry-press them into ceramic green bodies. Perform a binder removal treatment on the ceramic green bodies at 500℃ for 24 hours, followed by sintering at 1300℃ for 2 hours to prepare ceramic green bodies with a density ≥99%. Grind the ceramic green bodies on both sides to obtain ceramic plates with a thickness of 0.5 mm and a surface roughness Ra less than 0.1 μm. Place the ceramic plates into a hot bending mold, and then place them in a hot bending machine for hot bending. The hot bending temperature and the hot bending pressure bar load are shown in Table 2, resulting in a 3D ceramic shell.

[0114] Example 5, Comparative Examples 6, 7, and 8

[0115] Referring to Table 2 and the shell preparation method of Example 4, ceramic powder and shells of Examples 5, 6, 7, and 8 were prepared.

[0116] The main difference between Example 5 and Example 4 is that the content and composition of the plasticizing agent in the ceramic powder are different, and the hot bending temperature is different.

[0117] The main difference between Comparative Example 6 and Example 4 is that no plasticizing agent was added to the ceramic powder, and the hot bending temperature is different.

[0118] The main difference between Comparative Example 7 and Example 4 is that no plasticizing agent was added to the ceramic powder, and the hot bending temperature is different.

[0119] The main difference between Comparative Example 8 and Example 4 is that no plasticizing agent was added to the ceramic powder, and the hot bending temperature is different.

[0120] Referring to Example 1, the 3D ceramic shells obtained in Examples 4, 5, and Comparative Examples 6, 7, and 8 were tested, and the test results are shown in Table 2. Among them, when testing the pore density, the optical micrographs of the pore defects in Examples 4, 5, and Comparative Examples 7 and 8 are shown below. Figure 2 As shown.

[0121] Table 2

[0122]

[0123]

[0124]

[0125] Table 2 shows that adding plasticizing agents can reduce the hot bending temperature of black zirconia ceramics by 200-250℃, while reducing the pore density by 99% (from 115.4 pores / mm²). 2 Reduced to 0.6 particles / mm 2 Furthermore, the flexural strength and impact strength of the ceramic material did not change significantly. Figure 2It can be seen that, compared with comparative examples 7 and 8, examples 4 and 5 have fewer pore defects.

[0126] Examples 6, 7, 8, 9, and 10

[0127] Referring to Table 3 and the shell preparation method in Example 5, ceramic powders and shells for Examples 6, 7, 8, 9, and 10 were prepared.

[0128] The main difference between Example 6 and Example 5 is that the proportion of plasticizing agent in the main component is different.

[0129] The main difference between Example 7 and Example 5 is that the proportion of plasticizing agent in the main component is different.

[0130] The main difference between Example 8 and Example 5 is that rare earth oxides were not added.

[0131] The main difference between Example 9 and Example 5 is that the amounts of amorphous SiO2 and glass powder added are different.

[0132] The main difference between Example 10 and Example 5 is that no glass powder was added.

[0133] Referring to Example 1, the 3D ceramic shells obtained in Examples 6, 7, 8, 9, and 10 were tested, and the test results are shown in Table 3. Among them, when testing the pore density, the optical micrographs of the pore defects in Examples 6, 7, 8, 9, and 10 are shown below. Figure 3 As shown.

[0134] Table 3

[0135]

[0136]

[0137]

[0138] As shown in Table 3:

[0139] Based on the results of Example 6 (compared with Example 5), when the amount of plasticizing agent added accounts for 1.0 wt% of the main component, although it can be prepared into a shell by hot bending, the superplastic deformation ability of the ceramic is relatively reduced. At a lower temperature (1250°C), the ceramic cannot be fully hot bent, resulting in a shell with poor contour and high pore density.

[0140] Based on the results of Example 7 (compared with Example 5), when the amount of plasticizing agent added accounts for 1.0 wt% of the main component, although it is possible to prepare a shell by hot bending, the mechanical strength of the ceramic deteriorates and the grain size grows significantly.

[0141] Based on the results of Example 8 (compared with Example 5), when the plasticizer does not contain rare earth oxides, it affects the wettability of the plasticizer on the zirconia grains, resulting in the plasticizer not being able to fully coat the ceramic grains and not being able to fully reduce the grain slip stress. Although it can be prepared into a shell by hot bending, the ceramic cannot be fully hot bent at a lower temperature (1250°C), resulting in a shell with poor profile and high pore density.

[0142] Based on the results of Example 9 (compared with Example 5), when the proportion of amorphous SiO2 particles in the plasticizer is 5wt% and the proportion of glass powder in the plasticizer is 85wt%, the bonding force between the plasticizer and the grains is weak, resulting in insufficient ceramic grain boundary strength and a decrease in ceramic mechanical strength.

[0143] Based on the results of Example 10 (compared with Example 5), when the plasticizer does not contain glass powder, the viscosity of the plasticizer is high and the grain slip stress is large. Although it can be prepared into a shell by hot bending, the ceramic cannot be fully hot bent at a low temperature (1250°C), resulting in a shell with poor contour and high pore density.

[0144] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0145] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for preparing a ceramic product, wherein the ceramic product is a shell, characterized in that, Includes the following steps: Ceramic powder is prepared into ceramic green bodies; The ceramic green body is subjected to debinding and sintering treatment to prepare a ceramic plate; The ceramic plate is prepared into a ceramic product by hot bending forming, with a forming temperature of 1200℃~1250℃ and a forming pressure of 10N~200N. The ceramic powder comprises a main component and a plasticizing agent added to the main component, wherein the amount of the plasticizing agent added accounts for 2wt% to 5wt% of the main component. The main components include zirconium oxide, a stabilizer, and HfO2; the stabilizer includes at least one selected from Y2O3, CeO2, MgO, and CaO; the zirconium oxide accounts for 72wt% to 98wt% of the main components; the stabilizer accounts for 2wt% to 20wt% of the main components; and the HfO2 accounts for no more than 3wt% of the main components. The plasticizing agent comprises amorphous SiO2 particles, glass powder, and rare earth oxides. The glass powder comprises SiO2 and also includes at least one of Al2O3, MgO, ZnO, CaO, TiO2, SrO, and K2O. The rare earth oxides include at least one of La2O5, Sm2O3, Nd2O3, Er2O3, Y2O3, and CeO2. The amorphous SiO2 particles account for 10wt% to 80wt% of the plasticizing agent; the glass powder accounts for 5wt% to 70wt% of the plasticizing agent; the rare earth oxides account for 5wt% to 20wt% of the plasticizing agent; the SiO2 accounts for 10wt% to 80wt% of the glass powder; the Al2O3 accounts for no more than 50wt% of the glass powder; the MgO accounts for no more than 40wt% of the glass powder; and the ZnO accounts for no more than 40wt% of the glass powder. The proportion of CaO in the glass powder does not exceed 40 wt%; the proportion of TiO2 in the glass powder does not exceed 20 wt%. The proportion of SrO in the glass powder is no more than 10 wt%; and the proportion of K2O in the glass powder is no more than 10 wt%.

2. The method for preparing the ceramic product according to claim 1, characterized in that, The amount of the plasticizing agent added accounts for 3.4 wt% to 4.5 wt% of the main component.

3. The method for preparing the ceramic product according to claim 2, characterized in that, The particle size D50 of the amorphous SiO2 particles is less than 40 nm.

4. The method for preparing the ceramic product according to claim 1, characterized in that, The particle size D50 of the glass powder is less than 1 μm.

5. The method for preparing the ceramic product according to claim 1, characterized in that, The particle size D50 of the rare earth oxide is less than 200 nm.

6. The method for preparing the ceramic product according to claim 1, characterized in that, The amorphous SiO2 particles account for 15wt% to 65wt% of the plasticizing agent; the glass powder accounts for 25wt% to 70wt% of the plasticizing agent; and the rare earth oxides account for 9wt% to 15wt% of the plasticizing agent.

7. The method for preparing the ceramic product according to claim 1, characterized in that, The amorphous SiO2 particles account for 30.1 wt% to 50 wt% of the plasticizing agent; the glass powder accounts for 41 wt% to 56.1 wt% of the plasticizing agent; and the rare earth oxides account for 9 wt% to 13.8 wt% of the plasticizing agent.

8. The method for preparing the ceramic product according to any one of claims 1-7, characterized in that, The primary particle size of the zirconium oxide is D50 ≤ 100 nm.

9. The method for preparing the ceramic product according to claim 8, characterized in that, The main components also include colorants.

10. The method for preparing the ceramic product according to claim 9, characterized in that, The colorant includes at least one of AI2O3, ZnO, CoO, Fe2O3, Cr2O3, NiO, MnO, Er2O3, Nd2O3, Pr6O 11 , CuO, TiO2, Nb2O5, CaO, CeO2, and BaO.

11. The method for preparing the ceramic product according to claim 9, characterized in that, The colorant accounts for no more than 5 wt% of the main component.

12. A ceramic product, characterized in that, It is prepared by the method described in any one of claims 1-11.

13. An electronic device, characterized in that, include: The display screen, the motherboard, and the ceramic product as described in claim 12; The display screen is connected to the ceramic product, and a space is defined between the display screen and the ceramic product. The motherboard is located within the accommodating space and is electrically connected to the display screen.

Images