A ceramic structural member, method of making and use thereof

Abstract

This invention discloses a ceramic structural component, its preparation method, and its application. The ceramic structural component includes a zirconia ceramic substrate and a color-matching layer disposed on the inner surface of the zirconia ceramic substrate. The zirconia in the zirconia ceramic substrate has a tetragonal phase. The raw materials for preparing the color-matching layer include 5-30% by mass of pigment. The ceramic structural component of this invention can exhibit different degrees of color by adjusting the amount of pigment added to the color-matching layer. The color combination of the zirconia ceramic substrate and the color-matching layer allows for controllable adjustment of the final appearance color of the ceramic structural component. Furthermore, the color-matching layer of the ceramic structural component of this invention has high reliability and strong adhesion, and the zirconia ceramic substrate has high light transmittance, high ceramic density, small grain size, and high strength.

Description

Technical Field

[0001] This invention belongs to the field of ceramics, specifically relating to a ceramic structural component, its preparation method, and its application. Background Technology

[0002] To obtain purple ceramics, existing technologies involve adding ceramic pigments to the ceramic matrix to control the color. However, this method offers limited color control, and it's difficult to achieve the desired color by adjusting the formula when a range of shades, such as reddish-purple or bluish-purple, is required. Furthermore, ceramics obtained using this method generally suffer from low translucency, lack of texture, poor mechanical properties, and low strength, resulting in ceramic products that fail to meet usage requirements. Summary of the Invention

[0003] In order to overcome at least one of the technical problems existing in the prior art, one of the objectives of the present invention is to provide a ceramic structural component.

[0004] The second objective of this invention is to provide a method for preparing ceramic structural components.

[0005] The third objective of this invention is to provide a product.

[0006] The fourth objective of this invention is to provide an application of ceramic structural components in smart devices.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The first aspect of the present invention provides a ceramic structural component, comprising a zirconia ceramic substrate and a color-matching layer disposed on the inner surface of the zirconia ceramic substrate; the zirconia in the zirconia ceramic substrate has a tetragonal phase; the raw materials for preparing the color-matching layer include a colorant with a mass percentage of 5-30%.

[0009] This invention involves spraying a color-matching layer onto the inner surface of a zirconia ceramic substrate. This layer reflects light, causing the ceramic structural component to exhibit color changes, thus achieving color adjustment. For example, when the zirconia ceramic substrate is red and the color-matching layer is blue, the blue color-matching layer reflects blue light, enabling controllable color adjustment of the ceramic structural component from reddish-purple to bluish-purple.

[0010] Preferably, the zirconia ceramic substrate comprises the following molar percentage components: 1-5 mol% cerium oxide, 2-4 mol% yttrium oxide, and 91-97 mol% zirconia. When the CeO2 addition is less than 1 mol%, the zirconia ceramic substrate after reduction sintering is orange-colored, and after spraying a blue toning layer, the final ceramic structure cannot exhibit a purple effect. When the CeO2 addition is greater than 5 mol%, the zirconia ceramic substrate after reduction sintering is reddish-dark, with reduced transmittance. After spraying a blue toning layer, the blue cannot be displayed, and the ceramic structure appears dark red, failing to achieve a purple effect. When the Y2O3 addition is less than 2 mol%, the zirconia ceramic substrate has poor stability, is prone to deformation during sintering, and has poor aging performance, failing to meet the requirements for structural components used in smart wearable devices. When the Y2O3 addition is greater than 4 mol%, a cubic phase appears in the zirconia ceramic substrate, which is too stable, resulting in a weak phase transformation toughening effect and poor strength.

[0011] Preferably, the purity of the cerium oxide is greater than 99.9%.

[0012] In this invention, the zirconia ceramic substrate is a zirconia ceramic stabilized by both yttrium oxide and cerium oxide. The introduction of yttrium oxide aims to give the zirconia ceramic substrate a tetragonal phase, thereby increasing its strength. The introduction of high-purity cerium oxide (purity > 99.9%) is to give the zirconia ceramic substrate a red color and high transparency. Ordinary zirconia ceramics have low transmittance and cannot be used for color matching. The zirconia ceramic substrate in this invention is sintered once in an air atmosphere, and then reduced-sintered in a hydrogen or nitrogen-hydrogen mixed atmosphere, resulting in a cerium oxide layer that is red. 4+ Restored to Ce 3+ This invention introduces Ce in ionic form, allowing it to dissolve into the zirconia lattice during sintering. This reduces Ce enrichment at zirconia grain boundaries, thereby reducing light scattering centers and improving the ceramic's transmittance. The use of high-purity raw materials also aims to reduce the formation of heterogeneous phases from impurities in the zirconia ceramic, which would decrease its transmittance. Furthermore, high-temperature sintering promotes dense ceramic formation, reduces porosity, and further enhances the transmittance of the zirconia ceramic substrate. Specifically, with a zirconia ceramic substrate thickness of 1.0 mm, the transmittance at a wavelength of 600 nm is ≥45%.

[0013] Preferably, when the thickness of the zirconia ceramic substrate is 1.0 mm, the transmittance of the zirconia ceramic substrate at a wavelength of 600 nm is ≥45%.

[0014] Preferably, the molar percentage of cerium oxide is 2-4%. When the amount of CeO2 added is 2-4 mol%, the red hue of the zirconia ceramic substrate after reduction sintering is moderate, the transmittance is high, and after spraying a blue tinting layer, it can present a red-purple to blue-purple color effect with uniform color. By adjusting the cerium oxide content, the color of the zirconia ceramic substrate can be controlled from deep red to orange-red.

[0015] Preferably, the molar percentage of yttrium oxide is 2-3%. This invention achieves high strength in zirconia ceramic substrates by adjusting the yttrium oxide content.

[0016] Preferably, the raw materials for preparing the color-tone layer also include polyester resin and silane coupling agent.

[0017] Preferably, the polyester resin comprises 45-50% by mass, based on the total mass percentage of the raw materials used to prepare the color-tone layer being 100%.

[0018] Preferably, the amount of silane coupling agent added is 3%-5% of the total mass of polyester resin and blue pigment.

[0019] Preferably, the raw materials for preparing the color-tone layer also include a solvent.

[0020] In this invention, the role of polyester resin and silane coupling agent is mainly to form a film, thereby allowing the colorant to adhere to the inner surface of the zirconia ceramic substrate and form a color-matching layer.

[0021] Preferably, the polyester resin is selected from at least one of alkyd resin, polyallyl ester, phthalic acid resin, and polycarbonate.

[0022] Preferably, the silane coupling agent is selected from at least one of aminosilane, methoxysilane, chloropropylsilane, vinylsilane, epoxysilane, thiosilane, and methacryloxysilane.

[0023] Preferably, the colorant is a blue colorant. When the amount of blue colorant added is less than 5 wt%, the blue effect of the color-matching layer is not obvious and cannot meet the color matching requirements. After spraying the color-matching layer, the ceramic structural parts still show a red effect. When the amount of blue colorant added is greater than 30 wt%, the reliability of the color-matching layer decreases due to the excessive amount of colorant added. The color-matching layer is easy to fall off and has poor reliability, which cannot meet the usage requirements.

[0024] Preferably, the blue pigment is an organic pigment, an inorganic pigment, or a combination of both.

[0025] Preferably, the blue pigment is selected from at least one of phthalocyanine blue, indanthrene, cobalt oxide, and vanadium zirconium blue.

[0026] Preferably, the zirconia ceramic substrate contains Ce. 3+ion.

[0027] Preferably, the thickness of the color-correcting layer is 25–35 μm.

[0028] Preferably, the thickness of the zirconia ceramic substrate is 0.4-1 mm.

[0029] Preferably, the brightness L of the ceramic structural component is 61.2 to 73.2, the hue a is 2.3 to 9.2, and the hue b is -8.4 to -1.9.

[0030] Preferably, the surface roughness Ra of the zirconia ceramic substrate is less than 0.3 μm.

[0031] Preferably, the average grain size of the zirconia ceramic substrate is 360–440 nm. The grains in this invention have small size, high sintering activity, high sintering density, and higher strength.

[0032] Preferably, the density of the zirconia ceramic substrate is 6.0–6.2 g / cm³. 3 .

[0033] The second aspect of the present invention provides a method for preparing the ceramic structural component provided in the first aspect of the present invention, comprising the following steps:

[0034] S1: Cerium salt, zirconium oxychloride, and precipitant are mixed and reacted, then calcined to obtain powder;

[0035] S2: The powder, yttrium-stabilized zirconium oxide, and organic resin are mixed and granulated to obtain a mixed powder;

[0036] S3: The mixed powder is shaped into a green body; the green body is sintered once and then sintered a second time, and then polished to obtain a zirconia ceramic substrate;

[0037] S4: A color-matching layer is formed on the inner surface of the zirconia ceramic substrate to obtain the ceramic structural component.

[0038] Preferably, the cerium salt is selected from CeCl4, Ce(NO3)4, or a combination of both. This invention uses cerium salt as a raw material during preparation, achieving high transmittance of the zirconia ceramic substrate through ion introduction. Combined with an optimized formulation ratio of the color-tuning layer, the reflectivity of the blue phase in the color-tuning layer is increased, enabling controllable color tuning of the ceramic structural components from reddish-purple to bluish-purple.

[0039] Preferably, the precipitant is selected from ammonia, sodium hydroxide, or a combination of both.

[0040] Preferably, the mixing reaction time in step S1 is 2 to 4 hours.

[0041] Preferably, step S2 is: mixing the powder, yttrium-stabilized zirconium oxide, and solvent, grinding them, then mixing them with organic resin and granulating them to obtain a mixed powder; more preferably, step S2 is: mixing the powder, yttrium-stabilized zirconium oxide, and solvent, ball milling for 3-8 hours, then sand milling for 8-20 hours, then mixing them with organic resin and granulating them to obtain a mixed powder.

[0042] Preferably, the organic resin is selected from at least one of polyacrylic acid, hydroxypropyl methylcellulose, sodium carboxymethyl cellulose, triethanolamine, polyethylene glycol (PEG), and polystyrene amine.

[0043] Preferably, the primary sintering atmosphere is air.

[0044] Preferably, the primary sintering temperature is 1450–1500°C.

[0045] Preferably, the sintering time is 2 to 4 hours.

[0046] Preferably, the secondary sintering atmosphere is hydrogen or a mixture of nitrogen and hydrogen.

[0047] Preferably, the secondary sintering temperature is 1200–1300°C.

[0048] Preferably, the secondary sintering time is 10 to 15 hours.

[0049] Preferably, both the primary sintering step and the secondary sintering step are carried out under normal pressure.

[0050] Preferably, the molding step in step S3 is dry pressing or isostatic pressing.

[0051] Preferably, the polishing step in step S3 is as follows: polishing to make the surface roughness Ra of the zirconia ceramic substrate < 0.3 μm. The polishing step can further improve the light transmittance of the zirconia ceramic substrate.

[0052] Preferably, step S4 is: spraying a color-coating layer onto the inner surface of the zirconia ceramic substrate, and then baking and drying it to obtain the product.

[0053] This invention uses a normal pressure secondary sintering method to prepare zirconia ceramic substrates, which is lower in cost and more conducive to large-scale mass production compared to the existing technology that uses HIP treatment to reduce tetravalent cerium.

[0054] A third aspect of the present invention is to provide a product comprising the ceramic structural component provided in the first aspect of the present invention, the product including a smartphone and a smart wearable device.

[0055] Preferably, the smart wearable device includes a smartwatch, a smart bracelet, or smart clothing.

[0056] A fourth aspect of the present invention is to provide the application of the ceramic structural component provided in the first aspect of the present invention in a smart device.

[0057] The beneficial effects of the present invention are as follows: the ceramic structural component of the present invention can achieve different degrees of color by adjusting the amount of pigment added in the coloring layer. The color combination of the zirconia ceramic substrate and the coloring layer can achieve controllable adjustment of the final appearance color of the ceramic structural component. In addition, the coloring layer of the ceramic structural component of the present invention has high reliability and strong adhesion, and the zirconia ceramic substrate has high light transmittance, high ceramic density, small grain size, and high strength.

[0058] In this invention, the ceramic structural component can exhibit different degrees of red (from deep red to orange-red) on the zirconia ceramic substrate by adjusting the cerium oxide content. Simultaneously, adjusting the amount of blue pigment added to the color-matching layer allows for different degrees of blue effect in the color-matching layer. Through the color combination of the zirconia ceramic substrate and the color-matching layer, the overall color gradation of the ceramic structural component can be controlled from reddish-purple to bluish-purple. This invention is the first to use a high-strength, high-transmittance red zirconia ceramic substrate and achieves controllable color gradation of the ceramic structural component's appearance by spraying a blue color-matching layer onto a non-surface surface. The color-matching range can be adjusted from red to purple. Attached Figure Description

[0059] Figure 1 The image shows the XRD pattern of the red zirconia ceramic substrate in Example 1. Detailed Implementation

[0060] The following examples provide a more detailed description of the specific implementation of the present invention, but the implementation and protection of the present invention are not limited thereto. It should be noted that any processes not specifically described below are methods that can be implemented or understood by those skilled in the art by referring to existing technology. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0061] The purity of each raw material used in the embodiments and comparative examples of this invention is greater than >99.9%.

[0062] Example 1

[0063] This example provides a ceramic structural component, comprising a red zirconia ceramic substrate and a blue tinting layer disposed on the inner surface of the red zirconia ceramic substrate. The red zirconia ceramic substrate is composed of 1 mol% cerium oxide, 2 mol% yttrium oxide, and 97 mol% zirconia; the thickness of the red zirconia ceramic substrate is 1 mm. The thickness of the blue tinting layer is 30 μm. The raw materials for preparing the blue tinting layer are: 5% indanilide, 45% alkyd resin, and 1.8% aminosilane by mass percentage, with the balance being ethyl acetate as solvent. The formulation of the ceramic structural component in this example is shown in Table 1.

[0064] Table 1. Formulations of ceramic structural components in Examples 1-5 and Comparative Examples 1-6.

[0065]

[0066] Note: The raw materials for preparing the blue tint layer in Table 1 also include the solvent ethyl acetate. The amount of solvent added is such that the total mass percentage of the raw materials for preparing the blue tint layer is 100%.

[0067] The ceramic structural component in this example was prepared using the following method, with the specific steps as follows:

[0068] (1) Mix 10 mol CeCl4, 90 mol ZrOCl2 and pure water and stir for 3 h to form a homogeneous solution; then add 3% ammonia water, precipitate, filter, dry for 3 h, and calcine at 1100℃ to obtain colorant A;

[0069] (2) 20% by mass of pigment A and 80% by mass of yttrium-stabilized zirconium oxide (yttrium oxide mass fraction in yttrium-stabilized zirconium oxide is 3.8%) were ball-milled with pure water for 5 hours to mix evenly. Then, the mixture was further ground by sand milling for 12 hours to obtain a uniformly mixed slurry. 5% by mass of polyacrylic acid (calculated based on the mass fraction of the slurry being 100%) was added to the slurry, and the mixture was granulated to obtain formulation powder B.

[0070] (3) The formulation powder B is dry-pressed to obtain a blank C, and sintered for the first time in an air atmosphere at a temperature of 1450℃ for 2 hours to obtain a yellow sintered blank D; the blank D is sintered for the second time in a hydrogen atmosphere at a temperature of 1200℃ for 12 hours to obtain a red sintered body E.

[0071] (4) The sintered body E is polished on both sides to obtain a red zirconia ceramic substrate with high transparency;

[0072] (5) Spray blue ink onto the inner surface of a highly transparent red zirconia ceramic substrate and bake at 180°C to obtain the ceramic structural component in this example, the color of which can be controlled.

[0073] Examples 2-5

[0074] The ceramic structural components in Examples 2-5 differ from those in Example 1 in that:

[0075] (1) The amounts of cerium oxide, yttrium oxide and zirconium oxide in the red zirconium oxide ceramic substrate are different, as shown in Table 1;

[0076] (2) The amount of blue pigment used in the blue color layer is different, as shown in Table 1.

[0077] The ceramic structural components in Examples 2 to 5 can all be prepared by referring to the preparation method of the ceramic structural components in Example 1.

[0078] Tests showed that the red zirconia ceramic substrates in Examples 1-5 of this invention, with a thickness of 1 mm, all had a transmittance of ≥45% at a wavelength of 600 nm.

[0079] The red zirconia ceramic substrate in Example 1 was tested using an XRD analyzer, and the specific test results are shown in the figure below. Figure 1 As shown, where, Figure 1 (a) and Figure 1 (b) shows the measured and standard images of the red zirconia ceramic substrate in Example 1, respectively. Figure 1 It can be seen that the zirconia crystal phase in the red zirconia ceramic substrate of Example 1 is mainly tetragonal (accounting for 80.4%), and also contains some monoclinic phase (accounting for 19.6%), but no cubic phase. Tests showed that the zirconia crystal phase in the red zirconia ceramic substrates of Examples 2-5 is mainly tetragonal, and does not contain cubic phase.

[0080] Comparative Examples 1-6

[0081] The ceramic structural components in Comparative Examples 1-6 differ from those in Example 1 in that:

[0082] (1) The amounts of cerium oxide, yttrium oxide and zirconium oxide in the red zirconium oxide ceramic substrate are different, as shown in Table 1;

[0083] (2) The amount of blue pigment used in the blue color layer is different, as shown in Table 1.

[0084] The ceramic structural components in Comparative Examples 1 to 6 can all be prepared by referring to the preparation method of the ceramic structural components in Example 1.

[0085] Performance testing

[0086] The properties of the ceramic structural components in Examples 1-5 and Comparative Examples 1-6 were tested respectively, and the specific test methods are as follows:

[0087] (a) Bending strength: The bending strength of ceramic structural components was tested using the national standard GB / T 6569-2006 "Test Method for Bending Strength of Fine Ceramics".

[0088] (b) Colorimetric SCI: Colorimetric values ​​were tested using a SPECTROPHOTOMETER CM-2600d colorimeter. The thickness of the polished sheet was (0.4±0.03) mm. 10 pieces were tested per batch, and the average value was calculated.

[0089] (c) The ink reliability test shall be conducted in accordance with the National Standard GB9286-98 Cross-cut Test Method;

[0090] (d) Transmittance: The transmittance of the red zirconia ceramic substrate was tested according to the test methods in JISK7105 "Test Method for Optical Properties of Plastic Products" and JISK7361-1 "Test Method for Total Transmittance of Plastics and Transparent Materials". The specific test method is as follows: the thickness of the red zirconia ceramic substrate is 1 mm, and both sides of the red zirconia ceramic substrate are mirror-polished to a surface roughness Ra = 0.02 μm or less. A double-beam spectrophotometer (manufactured by Japan Spectrophotometer Co., Ltd., model V-650) was used for the measurement. Light emitted by the light source (deuterium lamp and halogen lamp) was transmitted and scattered in the sample, and the total transmittance and diffuse transmittance were measured using an integrating sphere. The measurement wavelength was 600 nm. The formula for calculating the linear transmittance is: Ti = Tt - Td, where Tt is the total transmittance (%), Td is the diffuse transmittance (%), and Ti is the linear transmittance (%).

[0091] The properties of the ceramic structural components in Examples 1-5 and Comparative Examples 1-6, measured according to the above test methods, are shown in Table 2 below.

[0092] Table 2 shows the properties of the ceramic structural components in Examples 1-5 and Comparative Examples 1-6.

[0093]

[0094]

[0095] As shown in Table 2, compared with Example 1, Comparative Example 1 reduced the cerium oxide content, while Comparative Example 2 increased the cerium oxide content. The strength of the ceramic structural parts prepared in Comparative Examples 1 and 2 was significantly reduced, and none of them could produce blue-purple ceramic structural parts. Compared with Example 2, Comparative Example 3 reduced the yttrium oxide content, while Comparative Example 4 increased the yttrium oxide content. The strength and average grain size of the ceramic structural parts prepared in Comparative Examples 3 and 4 were significantly reduced. Among them, the ceramic structural parts in Comparative Example 3 cracked during sintering. The ceramic structural parts prepared in Comparative Example 5 using a lower content of blue pigment could not exhibit purple color. The reliability of the ceramic structure prepared in Comparative Example 6 using a higher content of blue pigment was significantly reduced.

[0096] In summary, this invention achieves controllable color adjustment of the ceramic structural parts from deep red to orange-red by adjusting the cerium oxide content. At the same time, by adjusting the amount of blue pigment added to the blue color layer, the blue phase of the blue color layer and the reliability after spraying can be controlled. The combination of red zirconium oxide ceramic substrates with different red phases and blue color layers with different blue phases can achieve controllable color adjustment of the appearance of the final ceramic structural parts from red-purple to blue-purple.

[0097] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A ceramic structural component, characterized in that: The invention includes a zirconia ceramic substrate and a color-matching layer disposed on the inner surface of the zirconia ceramic substrate; the zirconia in the zirconia ceramic substrate has a tetragonal phase; the raw materials for preparing the color-matching layer include a colorant with a mass percentage of 5-30%; The zirconia ceramic substrate comprises the following components in molar percentages: 1-5 mol% cerium oxide, 2-4 mol% yttrium oxide, and 91-97 mol% zirconia. The colorant is a blue colorant; The zirconia ceramic substrate is red.

2. The ceramic structural component according to claim 1, characterized in that: When the thickness of the zirconia ceramic substrate is 1.0 mm, the transmittance of the zirconia ceramic substrate at a wavelength of 600 nm is ≥45%.

3. The ceramic structural component according to claim 1, characterized in that: The raw materials for preparing the color-tone layer also include polyester resin and silane coupling agent.

4. The ceramic structural component according to claim 3, characterized in that: Based on the total mass percentage of the raw materials used in preparing the color-tone layer being 100%, the mass percentage of the polyester resin is 45%. 50%; The amount of the silane coupling agent added is 3% of the total mass of the polyester resin and the blue pigment. 5%.

5. The ceramic structural component according to claim 1, characterized in that: The zirconia ceramic substrate contains Ce 3+ ion.

6. The ceramic structural component according to any one of claims 1 to 5, characterized in that: The brightness L of the ceramic structural component is 61.2~73.2, the hue a is 2.3~9.2, and the hue b is -8.4~-1.

9.

7. The method for preparing the ceramic structural component according to any one of claims 1 to 6, characterized in that: Includes the following steps: S1: Cerium salt, zirconium oxychloride, and precipitant are mixed and reacted, then calcined to obtain powder; S2: The powder, yttrium-stabilized zirconium oxide, and organic resin are mixed and granulated to obtain a mixed powder; S3: The mixed powder is shaped into a green body; the green body is sintered once and then sintered a second time, and then polished to obtain a zirconia ceramic substrate; S4: A color-matching layer is formed on the inner surface of the zirconia ceramic substrate to obtain the ceramic structural component.

8. The method for preparing ceramic structural components according to claim 7, characterized in that: The primary sintering step has at least one of the following characteristics: a1: The primary sintering atmosphere is air; a2: The primary sintering temperature is 1450~1500℃; a3: The sintering time for the first sintering is 2-4 hours; And / or, the secondary sintering step has at least one of the following characteristics: b1: The secondary sintering atmosphere is hydrogen or a mixture of nitrogen and hydrogen; b2: The secondary sintering temperature is 1200~1300℃; b3: The secondary sintering time is 10~15h.

9. A smart device, characterized in that: The invention includes the ceramic structural component as described in any one of claims 1 to 6, and the smart device includes a smartphone and a smart wearable device.

10. The application of the ceramic structural component according to any one of claims 1 to 6 in a smart device.

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