Infrared radiation ceramic coating structure
By introducing a conical protrusion or depression structure into the infrared radiation ceramic coating, the thermal radiation scattering effect is enhanced, solving the problem of low emissivity of existing coatings and improving the thermal efficiency and environmental performance of the kiln.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- PINGXIANG UNIV
- Filing Date
- 2025-05-30
- Publication Date
- 2026-05-15
AI Technical Summary
Existing infrared radiation coatings have a small radiation area and poor emissivity in industrial kilns, resulting in low and uneven heat transfer efficiency, leading to low energy utilization and environmental pollution.
An infrared radiation ceramic coating structure is designed, including a substrate layer and a radiation layer. The radiation layer has multiple conical protrusions or depressions. By increasing the scattering surface area and the conical tip scattering effect, the thermal radiation scattering effect is enhanced and the emissivity is improved.
It improves the emissivity of the coating, enhances the uniform distribution and transfer efficiency of heat, reduces the absorption and refractive index of the material, and improves the thermal efficiency and environmental performance of the kiln.
Smart Images
Figure CN224242986U_ABST
Abstract
Description
Technical Field
[0001] This disclosure belongs to the field of high temperature resistance, high emissivity, and functional materials technology, specifically relating to an infrared radiation ceramic coating structure. Background Technology
[0002] With the gradual growth of the industrial economy and the continuous expansion of the industrial system, the demand for high-temperature processing in metallurgy, ceramics, and chemical industries is increasing. While industrial kilns, as core equipment, ensure production efficiency, their high energy consumption, low thermal efficiency, and excessive carbon emissions are becoming increasingly prominent. The low emissivity of the materials inside the kilns leads to low heat transfer efficiency and uneven heat distribution, resulting in low energy utilization and serious environmental pollution. This issue has attracted the attention of governments and researchers worldwide. Currently, infrared radiation coatings are being used as functional materials to address this problem.
[0003] Infrared radiation coating is a functional material that achieves specific functions by controlling the infrared radiation characteristics of the material. It is currently widely used in the field of industrial energy conservation. Its principle is to utilize the high emissivity of the coating to enhance its infrared radiation energy output, allowing more heat energy to directly penetrate the medium in the form of electromagnetic waves and be efficiently transferred to the heated material. This significantly reduces energy loss during heat transfer, ensuring that heat is evenly distributed inside the kiln, thereby improving the kiln's thermal efficiency and reducing the emission of harmful gases.
[0004] Currently, infrared radiation coatings used in industry generally adopt a planar structure, resulting in a small radiation area and poor emissivity. Summary of the Invention
[0005] This disclosure aims to at least solve one of the technical problems existing in the prior art by providing an infrared radiation ceramic coating structure.
[0006] This disclosure provides an infrared radiation ceramic coating structure, including:
[0007] The substrate layer is used to coat the surface of the structure to be coated.
[0008] A radiation layer is disposed on the side of the substrate layer away from the structure to be coated. The radiation layer includes a plurality of conical protrusions disposed on the surface of the substrate layer, or a plurality of recessed structures recessed inside the substrate layer.
[0009] Optionally, the plurality of the conical protrusions or the plurality of the recesses are arranged at intervals or in a continuous manner.
[0010] Optionally, the cross-sectional dimensions of the conical protrusion structure gradually decrease from the base layer toward the outside.
[0011] Optionally, the cross-sectional dimensions of the recessed structure gradually decrease from the matrix layer toward its inner side.
[0012] Optionally, the tip of the conical protrusion has a needle-tip scattering effect.
[0013] Optionally, the aspect ratio of the conical protrusion or the recessed structure is (1-2):1.
[0014] Optionally, the height of the conical protrusion or the recessed structure is 0.15-0.25 mm.
[0015] Optionally, the width of the conical protrusion or the recessed structure is 0.1-0.2 mm.
[0016] Optionally, the thickness of the substrate layer is 0.25-0.35 mm.
[0017] Optionally, the materials of the substrate layer and the radiating layer include titanium-iron co-doped magnesium-chromium spinel fine powder, aluminum-chromium solid solution fine powder, and silicon micro powder.
[0018] This disclosure provides an infrared radiation ceramic coating structure, comprising: a substrate layer for covering the surface of a structure to be coated; and a radiation layer disposed on the side of the substrate layer opposite to the structure to be coated, wherein the radiation layer includes a plurality of conical protrusions disposed on the surface of the substrate layer, or a plurality of recesses recessed within the substrate layer. This disclosure increases the scattering surface area by appropriately roughening the substrate layer surface, leveraging the conical tip scattering effect to enhance the scattering of thermal radiation, increasing the projection depth of the material, thereby reducing the absorption index and refractive index of the material surface, and thus improving the emissivity of the coating. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the infrared radiation ceramic coating structure of Embodiment 1 of this disclosure;
[0020] Figure 2 This is a schematic diagram of the infrared radiation ceramic coating structure of Embodiment 2 of this disclosure;
[0021] Figure 3 For this disclosure Figure 2 Enlarged schematic diagram;
[0022] Figure 4 This is a schematic diagram of the infrared radiation ceramic coating structure of Embodiment 3 of this disclosure;
[0023] Figure 5 For this disclosure Figure 4 An enlarged schematic diagram. Detailed Implementation
[0024] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain this disclosure and represent a part of the embodiments of this disclosure, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the protection scope of this disclosure.
[0025] like Figures 2 to 5 As shown, this disclosure proposes an infrared radiation ceramic coating structure 100, including: a substrate layer 110 and a radiation layer 120, wherein the substrate layer 110 is used to cover the surface of the structure 200 to be coated; the radiation layer 120 is disposed on the side of the substrate layer 110 away from the structure 200 to be coated, and the radiation layer 120 includes a plurality of conical protrusions disposed on the surface of the substrate layer 110, or a plurality of recessed structures recessed inside the substrate layer.
[0026] In this embodiment, by further adding a radiation layer to the surface of the substrate layer, and by configuring the radiation layer as multiple conical protrusions or multiple recesses, the surface of the substrate layer is no longer smooth, forming a microstructure with a certain degree of roughness. This helps to increase the scattering surface area, enhance the scattering effect of thermal radiation, increase the projection depth of the material, and thus reduce the absorption index and refractive index of the material surface, thereby improving the emissivity of the coating. Especially when the radiation layer is composed of multiple conical protrusions, the top of each conical protrusion has a pinhead scattering part. When external thermal radiation interacts with the conical protrusions, the pinhead scattering effect of the conical protrusions enhances the scattering effect of thermal radiation. The enhanced scattering effect allows more thermal radiation to be scattered multiple times within the material, increasing the projection depth of the material, thereby reducing the absorption index and refractive index of the material surface, and ultimately improving the emissivity of the coating, enabling the coating to radiate heat outward more efficiently.
[0027] It should be noted that this embodiment does not specifically limit the structure of the radiation layer. Multiple conical protrusions or multiple recessed structures can be used. In some preferred embodiments, multiple conical protrusions are preferred, which can effectively improve the emissivity of the coating.
[0028] It should be further noted that this embodiment does not specifically limit the arrangement of multiple conical protrusions or multiple recesses. For example, multiple conical protrusions or multiple recesses can be arranged at intervals, or they can be arranged continuously. In some preferred embodiments, continuous arrangement is preferred.
[0029] It should be understood that the height in the aspect ratio of the raised or recessed structures given above refers to the thickness of the raised or recessed structure, and the width refers to the size of the widest area. An aspect ratio within this range can increase the surface area of the coating, thereby improving the absorption and emission efficiency of infrared radiation. An excessively high aspect ratio may lead to structural collapse or sintering deformation, while the above ratios maintain morphological stability at high temperatures (such as above 1200°C), making them particularly suitable for spinel coatings.
[0030] In some preferred embodiments, the height of the conical protrusion or the recessed structure is 0.15-0.25 mm, for example, 0.2 mm ± 0.01 mm. A larger conical protrusion height (0.2-0.25 mm) can enhance infrared absorption / emission efficiency, making it suitable for high-temperature radiation coatings (such as kiln energy saving).
[0031] In some other preferred embodiments, the width of the conical protrusion or recess is 0.1–0.2 mm ± 0.01 mm.
[0032] It should be noted that the application fields of the infrared radiation ceramic coating structure in this embodiment are not specifically limited. For example, it can be used for efficient heat dissipation in kilns, automobiles, aircraft, or other industries, as well as for environmental protection. For example, the structure to be coated can be insulating bricks or insulating cotton inside a kiln, with insulating bricks being preferred. Furthermore, the thickness of the substrate layer is 0.25-0.35 mm, preferably 0.25 mm, 0.3 mm, or 0.35 mm. By setting the ratio of the substrate layer thickness to the radiation layer thickness to (1-2):1, the substrate layer of the aforementioned thickness provides sufficient mechanical support (such as thermal shock resistance), while the height of the radiation layer is sufficient to enhance infrared radiation efficiency. The substrate layer thickness being greater than the radiation layer effectively disperses thermal stress (such as kiln thermal circulation) and prevents coating cracking.
[0033] It should be noted that, based on the infrared radiation ceramic coating structure comprising a substrate layer and a radiation layer, when the thickness of the radiation layer is preferably 0.15-0.25 mm and the thickness of the substrate layer is preferably 0.25-0.35 mm, the total thickness of the infrared radiation ceramic coating structure can preferably be 0.4-0.6 mm, for example, 0.5 ± 0.01 mm.
[0034] It should be noted that the materials of the substrate layer and the radiating layer in this embodiment include titanium-iron co-doped magnesium-chromium spinel fine powder, aluminum-chromium solid solution fine powder, silicon micro powder, and aluminum dihydrogen phosphate solution. The above materials form a coating slurry, which is then used to achieve structural shaping via plasma spraying or a template method.
[0035] The infrared radiation coating slurry of this embodiment is prepared by using (40-70 wt%) titanium-iron co-doped magnesium-chromium spinel fine powder, (16-22 wt%) aluminum-chromium solid solution fine powder, (4-9 wt%) silicon micro powder, and (5-30 wt%) aluminum dihydrogen phosphate solution as raw materials, and adding (20-50 wt%) of the above coating raw materials with deionized water. The mixture is ball-milled in a planetary ball mill for 1-2 hours with a ball-to-material ratio of 3:1 to obtain the coating slurry. The structure is then achieved by plasma spraying and template method.
[0036] In some preferred embodiments, in the titanium-iron co-doped magnesium-chromium spinel fine powder, magnesium oxide, chromium trioxide, titanium dioxide, and iron oxide are mixed in a molar ratio (Cr2O3+TiO2+Fe2O3:MgO=1:1.25).
[0037] The aluminum-chromium solid solution fine powder contains a mixture of chromium trioxide and aluminum oxide (the molar ratio of Cr2O3 to Al2O3 is ≤1:10).
[0038] The aluminum dihydrogen phosphate solution requires an Al(H2PO4)3 content ≥ 30%. Molding.
[0039] This disclosure involves appropriately increasing the roughness of the substrate layer surface to form a radiation layer with multiple conical protrusions or multiple recesses. The tip scattering effect of the cone helps to increase the scattering surface area, enhance the scattering effect of thermal radiation, and increase the projection depth of the material. Therefore, it reduces the absorption index and refractive index of the material surface, thereby improving the emissivity of the coating.
[0040] The structure of the infrared radiation ceramic coating will be further explained below with reference to specific embodiments:
[0041] Example 1
[0042] like Figure 1 As shown, the infrared radiation ceramic coating structure in this example is a flat layer structure coating, that is, the infrared radiation ceramic coating structure 100 only includes the substrate layer 110 structure, which covers the inner wall 200 of the kiln.
[0043] This embodiment employs a traditional flat-layer coating structure. The raw materials are 46 wt% titanium-iron co-doped magnesium-chromium spinel fine powder, (16-22 wt%) aluminum-chromium solid solution fine powder, (4-9 wt%) silicon micropowder, and (5-30 wt%) aluminum dihydrogen phosphate solution, with the addition of (20-50 wt%) deionized water. The mixture is ball-milled in a planetary ball mill for 1-2 hours at a ball-to-material ratio of 3:1 to obtain the coating slurry. This slurry is then applied to the inner wall of a kiln using a spray coating method to form a substrate layer. The total thickness of this coating is 0.5 mm. The average infrared emissivity of this coating at room temperature is 0.88, and after 10 cycles of thermal shock at 800℃, no peeling, cracking, or flaking occurs.
[0044] Example 2
[0045] like Figure 2 and Figure 3 As shown, the infrared radiation ceramic coating structure 100 of this example includes a substrate layer 110 and a radiation layer 120 located above the substrate layer 110. The lower surface of the substrate layer 110 covers the inner wall 200 of the kiln. The radiation layer 120 includes a plurality of conical protrusions continuously distributed on the substrate layer 110. The top of the conical protrusions has a needle tip structure and has a needle tip scattering effect.
[0046] This embodiment uses a serrated radiant layer formed by conical protrusions as a component unit for illustration. The raw material preparation is the same as in Example 1, and the serrated structure is formed by plasma spraying and template method. The total thickness H of the infrared radiant ceramic coating structure is 0.5 mm, the thickness of the substrate layer 110 is 0.3 mm, the thickness of the conical protrusion structure is 0.2 mm, the height h of a single conical protrusion structure is 0.2 mm ± 0.01 mm, the width w (i.e., the diameter of the cone base of the conical protrusion structure) is 0.2 mm ± 0.01 mm, and the height-to-width ratio of the conical protrusion structure is 1:1. Thus, the infrared radiant ceramic coating structure of this embodiment has an average infrared emissivity of 0.92 at room temperature, which is 4.50% higher than the emissivity of the planar structure coating in Example 1. After 10 cycles of thermal shock at 800℃, there is no peeling, cracking, or flaking, and the thermal efficiency of industrial kilns is simultaneously improved.
[0047] Example 3
[0048] Reference Figure 4 and Figure 5 The infrared radiation ceramic coating structure 100 of this example includes a substrate layer 110 and a radiation layer 120 located above the substrate layer. The substrate layer 110 covers the inner wall 200 of the kiln. The radiation layer 120 includes a plurality of conical protrusions continuously distributed on the substrate layer 110. The top of the conical protrusions has a needle-tip structure, which has a needle-tip scattering effect.
[0049] This embodiment uses a serrated radiant layer formed by conical protrusions as a component unit for illustration. The raw material preparation is the same as in Example 1, and the serrated structure is formed by plasma spraying and template method. The total thickness H of the infrared radiant ceramic coating structure is 0.5 mm, the thickness of the substrate layer 110 is 0.3 mm, the thickness of the conical protrusion structure is 0.2 mm, the height h of a single conical protrusion structure is 0.2 mm ± 0.01 mm, the width w (i.e., the diameter of the cone base of the conical protrusion structure) is 0.1 mm ± 0.01 mm, and the height-to-width ratio of the conical protrusion structure is 2:1. Thus, the infrared radiant ceramic coating structure of this embodiment has an average infrared emissivity of 0.95 at room temperature, which is 7.95% higher than the emissivity of the planar structure coating in Example 1. After 10 cycles of thermal shock at 800℃, there is no peeling, cracking, or flaking, and the thermal efficiency of industrial kilns is simultaneously improved.
[0050] In summary, under certain thickness conditions, the infrared radiation coating structure formed by the conical protrusion structure has an effective radiation area that is 10-20% higher than that of the traditional planar structure coating. The average emissivity of this structure coating can reach 0.92-0.95, which is 4-8% higher than that of the planar structure of the same material.
[0051] It should be noted that the structure to be coated in the above embodiments is only illustrated using the kiln as an example. In other embodiments, it can also be the structure to be coated in other fields such as automobiles or airplanes, which will not be listed here.
[0052] It should also be noted that the radiation layer in the above embodiment is illustrated using a conical protrusion structure as an example. In other embodiments, the radiation layer may also be a recessed structure, etc., which will not be listed here.
[0053] This disclosure proposes an infrared radiation ceramic coating structure, which has the following advantages over the prior art:
[0054] First, this disclosure effectively increases the surface roughness of the substrate layer by adding a radiation layer to the surface of the substrate layer. Through the combination of the substrate layer and the radiation layer, the scattering effect of thermal radiation is effectively enhanced, and the projection depth of the material is increased.
[0055] Secondly, the radiation layer disclosed herein can adopt a conical protrusion structure or a concave structure, which helps to increase the specific surface area of the substrate layer, exert the conical tip scattering effect, and thus improve the emissivity of the coating.
[0056] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.
Claims
1. An infrared radiation ceramic coating structure, characterized in that, include: The substrate layer is used to coat the surface of the structure to be coated. A radiation layer is disposed on the side of the substrate layer away from the structure to be coated. The radiation layer includes a plurality of conical protrusions disposed on the surface of the substrate layer, or a plurality of recessed structures recessed inside the substrate layer.
2. The infrared radiation ceramic coating structure according to claim 1, characterized in that, The conical protrusions or the recesses are arranged at intervals or in a continuous manner.
3. The infrared radiation ceramic coating structure according to claim 1, characterized in that, The cross-sectional dimensions of the conical protrusion structure gradually decrease from the base layer outwards.
4. The infrared radiation ceramic coating structure according to claim 1, characterized in that, The cross-sectional dimensions of the recessed structure gradually decrease from the matrix layer toward its inner side.
5. The infrared radiation ceramic coating structure according to claim 1, characterized in that, The aspect ratio of the conical protrusion or the recessed structure is (1-2):
1.
6. The infrared radiation ceramic coating structure according to claim 5, characterized in that, The height of the conical protrusion or the recessed structure is 0.15-0.25 mm.
7. The infrared radiation ceramic coating structure according to claim 5, characterized in that, The width of the conical protrusion or the recessed structure is 0.1-0.2 mm.
8. The infrared radiation ceramic coating structure according to any one of claims 1 to 7, characterized in that, The thickness of the substrate layer is 0.25-0.35 mm.
9. The infrared radiation ceramic coating structure according to any one of claims 1 to 7, characterized in that, The thickness of the infrared radiation ceramic coating structure is 0.4-0.6 mm.