Panels and appliances

Abstract

The present invention provides a panel and an electrical appliance. The panel comprises: a first material layer; and a second material layer disposed on one side of the first material layer, wherein the density of the first material layer is greater than that of the second material layer, and the porosity of the first material layer is lower than that of the second material layer. In the panel provided by the present invention, the density of the first material layer is greater than that of the second material layer, that is, the first material layer is easier to densify and sinter. Since the second material layer has a lower density and a higher porosity than the first material layer, the gaps between the grains of the second material layer are larger than those of the first material layer. This allows the second material layer to offset the volume expansion caused by thermal expansion of the particles through the gaps, thereby preventing cracking of the panel when heated to high temperatures. The lower porosity of the first material layer prevents liquid from penetrating through the first material layer into the second material layer, thereby preventing leakage of electronic devices beneath the second material layer.

Description

Technical Field

[0001] The present invention relates to the technical field of household appliances, and in particular to a panel and an appliance. Background Art

[0002] Induction cookers are common household appliances that don't require an open flame for heating. Instead, they utilize a coiled coil to generate a magnetic field, generating eddy currents that heat the surface of a magnetic cookware. They are popular for their convenience and safety, making them a popular choice for home cooking.

[0003] Currently, induction cooktops are made of lithium-aluminum-silicon glass-ceramic material, which has a low coefficient of expansion and high strength, so cooking on glass-ceramic does not worry about cracking. With the passage of time, rock slabs, due to their unique appearance and texture, have become popular among young people, and replacing glass-ceramic panels with rock slabs has become a hot market development. However, rock slabs are not heat-resistant when heated at high temperatures and are prone to cracking. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] To this end, a first aspect of the present invention provides a panel.

[0006] A second aspect of the present invention further provides an electrical appliance.

[0007] In view of this, the first aspect of the present invention proposes a panel, comprising: a first material layer; a second material layer, arranged on one side of the first material layer, wherein the density of the first material layer is greater than the density of the second material layer, and the porosity of the first material layer is lower than the porosity of the second material layer.

[0008] The panel provided by the present invention includes a first material layer and a second material layer arranged on one side of the first material layer. The density of the first material layer is greater than that of the second material layer, that is, the first material layer is easier to densify and sinter. Since the second material layer has a lower density than the first material layer and a higher porosity than the first material layer, the gaps between the grains of the second material layer are larger than those of the first material layer, so that the second material layer can offset the volume expansion caused by the thermal expansion of the particles through the gaps, thereby preventing the panel from cracking when heated at high temperatures. The porosity of the first material layer is lower than that of the second material layer. In this way, in panel application scenarios such as induction cookers, when the panel needs to come into contact with water during the cooking process or utensil cleaning, it can prevent liquid from penetrating into the second material layer through the first material layer, thereby preventing leakage of electronic devices under the second material layer, ensuring the safe use of household appliances.

[0009] The panel provided according to the present invention may also have the following additional technical features:

[0010] In some possible designs, the expansion coefficient of the first material layer is lower than the expansion coefficient of the second material layer, wherein the crystal phase of the first material layer includes a negative expansion crystal phase.

[0011] In this design, the first material layer has a lower coefficient of expansion than the second material layer. This prevents cracking in the first material layer when the panel is heated, ensuring a good match between the first and second material layers and ensuring the overall heat resistance of the panel. The first material layer includes a negative expansion phase within its crystalline phase, significantly reducing its overall coefficient of expansion.

[0012] In some possible designs, the first material layer and the second material layer both contain silicon and oxygen, with the weight percentage of the silicon being greater than or equal to 10%, and the weight percentage of the oxygen being greater than or equal to 30%.

[0013] In this design, the first material layer and the second material layer both contain more than 10% silicon and more than 30% oxygen. During sintering, the silicon and oxygen elements can form silicon-oxygen-silicon chemical bonds, thereby enhancing the bonding strength between the first material layer and the second material layer, and preventing the first material layer and the second material layer from detaching under external impact or high temperature environment.

[0014] In some possible designs, the first material layer further includes lithium and / or magnesium, and the second material layer further includes magnesium.

[0015] In this design, the first material layer also includes lithium and / or magnesium elements, and the second material layer also includes magnesium elements, so that the first material layer has a higher density after sintering, and at the same time, the first material layer forms a larger volume shrinkage. Since the shrinkage rate of the second material layer during sintering is low, surface compressive stress is formed when the first material layer shrinks, and thermal shock is mainly tensile stress, so the cracking caused by thermal stress can be further slowed down during the thermal shock process; the second material layer also includes magnesium elements, so that the second material layer has a lower thermal expansion coefficient.

[0016] In some possible designs, the crystal phase of the first material layer includes a lithium-aluminum-silicon-oxygen crystal phase, and the crystal phase of the second material layer includes a magnesium-aluminum-silicon-oxygen crystal phase.

[0017] In this design, the first material layer also includes lithium, and the crystalline phases in the first material layer include a lithium-aluminum-silicon-oxygen crystalline phase. On the one hand, lithium forms Li2O (lithium oxide) during sintering. Lithium oxide is an alkali metal oxide flux. When sintered at high temperature, it forms a liquid glass phase, which fills the gaps between the particles and promotes the densification and sintering of the first material layer, resulting in a higher density after sintering. At the same time, it causes the first material layer to undergo a larger volume shrinkage. Since the second material layer has a lower shrinkage rate during sintering, the first material layer forms surface compressive stress when shrinking, while the thermal shock is mainly tensile stress. Therefore, it can further mitigate cracking caused by thermal stress during thermal shock. In addition, the lithium element and other elements in the first material layer form a lithium-aluminum-silicon-oxygen crystalline phase with a negative thermal expansion coefficient, which can significantly reduce the overall thermal expansion coefficient of the first material layer. The crystalline phases of the second material layer include a magnesium-aluminum-silicon-oxygen crystalline phase, which gives the second material layer a lower thermal expansion coefficient. Therefore, when the panel is subjected to thermal shock, it can improve the heat resistance of the panel and prevent the panel from cracking due to excessive expansion.

[0018] In some possible designs, in the first material layer, the weight percentage of the lithium element is greater than 0% and less than or equal to 5%, the weight percentage of the magnesium element is greater than or equal to 0% and less than or equal to 8%, the weight percentage of the aluminum element is greater than or equal to 5% and less than or equal to 15%, the weight percentage of the silicon element is greater than or equal to 20% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%.

[0019] In this design, the first material layer contains lithium, magnesium, aluminum, silicon, and oxygen. The weight percentage of lithium is between 0% and 5%, which can not only achieve densification sintering of the first material layer but also reduce the cost of the first material layer. The weight percentage of magnesium is greater than or equal to 0% and less than or equal to 8%, the weight percentage of aluminum is greater than or equal to 5% and less than or equal to 15%, the weight percentage of silicon is greater than or equal to 20% and less than or equal to 45%, and the weight percentage of oxygen is greater than or equal to 30% and less than or equal to 60%, which can not only ensure the bonding strength between the first material layer and the second material layer, but also enable the first material layer to form a negative expansion coefficient crystal phase.

[0020] In some possible designs, in the second material layer, the weight percentage of the magnesium element is greater than or equal to 1% and less than or equal to 15%, the weight percentage of the aluminum element is greater than or equal to 10% and less than or equal to 25%, the weight percentage of the silicon element is greater than or equal to 10% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%.

[0021] In this design, the second material layer contains magnesium, aluminum, silicon and oxygen elements, wherein the weight percentage of magnesium is greater than or equal to 1% and less than or equal to 15%, the weight percentage of aluminum is greater than or equal to 10% and less than or equal to 25%, the weight percentage of silicon is greater than or equal to 10% and less than or equal to 45%, and the weight percentage of oxygen is greater than or equal to 30% and less than or equal to 60%, so that the second material layer can synthesize a crystalline phase with a low expansion coefficient, and at the same time, it can also form aluminum oxide through aluminum and oxygen elements, thereby improving the bonding strength between the first material layer and the second material layer.

[0022] In some possible designs, the thickness of the first material layer is greater than or equal to 50 μm and less than or equal to 500 μm; the porosity of the first material layer is less than or equal to 1%; the expansion coefficient of the first material layer within a preset temperature range is greater than or equal to 0×10 -6 / K, and less than or equal to 1.5×10 -6 / K. In this design, if the first material layer is too thick, it will increase the manufacturing cost and produce a large stress difference, which will easily cause the first material layer to crack. If the thickness of the first material layer is too thin, it will lead to insufficient panel strength, which will easily cause the first material layer to crack when subjected to mechanical impact. Therefore, the thickness of the first material layer is set between 50μm and 500μm to ensure the strength of the first material layer. The porosity of the first material layer is less than or equal to 1%, which can prevent liquid from entering the second material layer from the first material layer and then entering the internal components through the second material layer to cause leakage. The expansion coefficient of the first material layer within the preset temperature range is greater than or equal to 0×10 -6 / K, and less than or equal to 1.5×10 -6 / K, so that the first material layer has a lower expansion coefficient, so that the first material layer can be prevented from cracking when the panel is heated at high temperature.

[0023] Specifically, the preset temperature range is from room temperature to 1000° C. Further, the room temperature is greater than or equal to 10° C. and less than or equal to 30° C.

[0024] In some possible designs, the thickness of the second material layer is greater than or equal to 5 mm and less than or equal to 10 mm; the porosity of the second material layer is greater than or equal to 10% and less than or equal to 25%; the expansion coefficient of the second material layer within a preset temperature range is greater than or equal to 1.5×10 -6 / K, and less than or equal to 3.5×10 -6 / K.

[0025] In this design, if the thickness of the second material layer is too thick, the thickness of the entire panel will be too thick, the material will be too much, and the cost will be too high. If the thickness of the second material layer is too small, the strength will be too low and will not meet the mechanical impact requirements. Therefore, the thickness of the second material layer is set between 5mm and 10mm, which not only ensures the strength of the panel but also reduces the manufacturing cost. The porosity of the second material layer is between 10% and 25%, which not only satisfies the second material layer's offsetting effect on the thermal expansion of the internal particles, but also ensures the strength of the panel. The expansion coefficient of the second material layer within the preset temperature range is greater than or equal to 1.5×10 -6 / K, and less than or equal to 3.5×10 -6 / K, so that the second material layer has a lower expansion coefficient, thereby preventing the panel from cracking when heated at high temperature.

[0026] In some possible designs, the ratio of the thickness of the second material layer to the thickness of the first material layer is greater than or equal to 10 and less than or equal to 200.

[0027] In this design, the ratio of the thickness of the second material layer to the thickness of the first material layer is between 10 and 200, which can ensure the strength of the panel and meet the mechanical impact requirements.

[0028] In a specific application, the thickness of the first material layer is greater than or equal to 50 micrometers and less than or equal to 500 micrometers.

[0029] In some possible designs, the panel further includes: a waterproof layer, disposed on a side of the first material layer facing away from the second material layer.

[0030] In this design, a waterproof layer is provided on the side of the first material layer facing away from the second material layer. The waterproof layer has a waterproof effect and can further prevent liquid from flowing through the second material layer into the components below, thereby avoiding leakage.

[0031] In some possible designs, the first material layer and the second material layer are an integral sintered structure.

[0032] In this design, the first and second material layers are sintered together, allowing atomic diffusion between the particles to form sintered necks, which improves the mechanical strength of the panel. It also allows the first material layer to form a highly dense structure through sintering.

[0033] According to a second aspect of the present invention, an electrical appliance is further provided, comprising: a panel as provided in any of the above technical solutions.

[0034] The electrical appliance provided in the second aspect of the present invention comprises the panel proposed in any of the above technical solutions and therefore has all the beneficial effects of the panel.

[0035] Additional aspects and advantages of the invention will become apparent from the description which follows, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0037] Figure 1 A schematic diagram showing the microstructure of a panel according to an embodiment of the present invention is shown;

[0038] Figure 2 A schematic diagram of the microstructure of the second material layer according to an embodiment of the present invention is shown.

[0039] in, Figure 1 and Figure 2 The corresponding relationship between the reference numerals and component names is as follows:

[0040] 1 panel, 10 first material layer, 12 second material layer. DETAILED DESCRIPTION

[0041] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0043] Refer to the following Figure 1 and Figure 2 The panel 1 and the electrical appliance according to some embodiments of the present invention are described.

[0044] like Figure 1 and Figure 2 As shown, according to an embodiment of the first aspect of the present invention, the present invention proposes a panel 1, comprising: a first material layer 10; a second material layer 12, arranged on one side of the first material layer 10, wherein the density of the first material layer 10 is greater than the density of the second material layer 12, and the porosity of the first material layer 10 is lower than the porosity of the second material layer 12.

[0045] The panel 1 provided by the present invention includes a first material layer 10 and a second material layer 12 disposed on one side of the first material layer 10. The density of the first material layer 10 is greater than that of the second material layer 12, that is, the first material layer 10 is easier to densify and sinter. Since the second material layer 12 has a lower density and a greater porosity than the first material layer 10, the gaps between the grains of the second material layer 12 are larger than those of the first material layer 10. This allows the second material layer 12 to offset the volume expansion caused by the thermal expansion of the particles through the gaps, thereby preventing the panel 1 from cracking when heated at high temperatures. The porosity of the first material layer 10 is lower than that of the second material layer 12. In this way, when the panel 1 comes into contact with water in an application scenario, it can prevent liquid from penetrating through the first material layer 10 into the second material layer 12, thereby preventing leakage of electronic devices below the second material layer 12.

[0046] It is understandable that the present application provides a double-layer structure for the panel 1, with the surface layer being the first material layer 10 and the bottom layer being the second material layer 12. The density of the first material layer 10 is greater than that of the second material layer 12, and therefore the density of the second material layer 12 is lower than that of the first material layer 10. Compared to the first material layer 10, the second material layer 12 has a lower density, and the gaps between the grains within it are larger. In this way, when the panel 1 is heated, these gaps can offset the volume expansion caused by the thermal expansion of the particles, thus macroscopically preventing the ceramic plate from cracking when heated at high temperatures. Accordingly, the higher density of the first material layer 10 results in a lower porosity, thus providing better waterproof performance.

[0047] It should be noted that the material components of the first material layer 10 of the surface layer are easier to densify and sinter, and there are gaps between the grains of the second material layer 12.

[0048] In a specific application, the panel 1 is sintered.

[0049] According to one embodiment of the present application, the expansion coefficient of the first material layer 10 is lower than the expansion coefficient of the second material layer 12 , wherein the crystal phase of the first material layer 10 includes a negative expansion crystal phase.

[0050] In this embodiment, the expansion coefficient of the first material layer 10 is lower than that of the second material layer 12. Thus, when the panel 1 is heated, the lower expansion coefficient of the first material layer 10 prevents cracking of the first material layer 10, ensuring that the first material layer 10 and the second material layer 12 are compatible, thereby ensuring the overall heat resistance of the panel 1. Furthermore, the crystalline phase of the first material layer 10 includes a negative expansion crystalline phase, which significantly reduces the overall expansion coefficient of the first material layer 10.

[0051] In a specific application, the crystal phase of the second material layer 12 includes a low expansion crystal phase, so that the expansion coefficient of the second material layer 12 is low, thereby improving the heat resistance of the panel 1 when the panel 1 is heated and preventing the panel 1 from cracking.

[0052] According to an embodiment of the present application, the first material layer 10 and the second material layer 12 both contain silicon and oxygen, with the weight percentage of silicon being greater than or equal to 10%, and the weight percentage of oxygen being greater than or equal to 30%.

[0053] In this embodiment, the first material layer 10 and the second material layer 12 both contain more than 10% silicon and more than 30% oxygen. During sintering, the silicon and oxygen elements can form silicon-oxygen-silicon chemical bonds, thereby enhancing the bonding strength between the first material layer 10 and the second material layer 12, and preventing the first material layer 10 and the second material layer 12 from detaching under external impact or high temperature environment.

[0054] According to one embodiment of the present application, the first material layer 10 further includes lithium and / or magnesium, and the second material layer 12 further includes magnesium.

[0055] In this embodiment, the first material layer 10 also includes lithium and / or magnesium elements, and the second material layer 12 also includes magnesium elements, so that the first material layer 10 has a higher density after sintering, and at the same time, the first material layer 10 forms a larger volume shrinkage. Since the shrinkage rate of the second material layer 12 during sintering is low, surface compressive stress is formed when the first material layer 10 shrinks, and the thermal shock is mainly tensile stress, so the cracking caused by thermal stress can be further slowed down during the thermal shock process; the second material layer 12 also includes magnesium elements, so that the second material layer 12 has a lower thermal expansion coefficient.

[0056] According to one embodiment of the present application, the crystal phase of the first material layer 10 includes a lithium-aluminum-silicon-oxygen crystal phase, and the crystal phase of the second material layer 12 includes a magnesium-aluminum-silicon-oxygen crystal phase.

[0057] In this embodiment, the first material layer 10 also includes lithium, and the crystalline phase in the first material layer 10 includes a lithium-aluminum-silicon-oxygen crystalline phase. On the one hand, the lithium element forms Li2O (lithium oxide) during sintering. Lithium oxide is an alkali metal oxide flux. When sintered at high temperature, it will form a liquid glass phase, which will fill the gaps between the particles and promote the densification sintering of the first material layer 10, so that the first material layer 10 has a higher density after sintering. At the same time, the first material layer 10 forms a larger volume shrinkage. Since the shrinkage rate of the second material layer 12 during sintering is low, the first material layer 10 forms surface compressive stress when shrinking, while the thermal shock is mainly tensile stress. Therefore, the cracking caused by thermal stress can be further alleviated during the thermal shock process. In addition, the lithium element and other elements in the first material layer 10 form a lithium-aluminum-silicon-oxygen crystalline phase with a negative expansion coefficient, which can significantly reduce the overall thermal expansion coefficient of the first material layer 10. The crystal phase of the second material layer 12 includes a magnesium-aluminum-silicon-oxygen crystal phase, so that the second material layer 12 has a lower thermal expansion coefficient, thereby improving the heat resistance of the panel 1 when the panel 1 is subjected to thermal shock, and preventing the panel 1 from cracking due to excessive expansion.

[0058] It can be understood that the magnesium-aluminum-silicon-oxygen crystal phase is a low expansion coefficient crystal phase.

[0059] According to one embodiment of the present application, in the first material layer 10, the weight percentage of the lithium element is greater than or equal to 0% and less than or equal to 5%, the weight percentage of the magnesium element is greater than or equal to 0% and less than or equal to 8%, the weight percentage of the aluminum element is greater than or equal to 5% and less than or equal to 15%, the weight percentage of the silicon element is greater than or equal to 20% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%.

[0060] In this embodiment, the first material layer 10 contains lithium, magnesium, aluminum, silicon, and oxygen. The weight percentage of lithium is between 0% and 5%, which can achieve densification sintering of the first material layer 10 and reduce the cost of the first material layer 10. The weight percentage of magnesium is greater than or equal to 0% and less than or equal to 8%, the weight percentage of aluminum is greater than or equal to 5% and less than or equal to 15%, the weight percentage of silicon is greater than or equal to 20% and less than or equal to 45%, and the weight percentage of oxygen is greater than or equal to 30% and less than or equal to 60%, which can ensure the bonding strength between the first material layer 10 and the second material layer 12 and enable the first material layer 10 to form a negative expansion coefficient crystal phase.

[0061] In specific applications, the weight percentage of lithium element is any value among: 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, and 4.5%.

[0062] The weight percentage of magnesium element is any value among 1%, 2%, 3%, 4%, 5%, 6% and 7%.

[0063] The weight percentage of the aluminum element is any value among 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, and 14%.

[0064] The weight percentage of silicon element is any value among 22%, 25%, 28%, 30%, 32%, 35%, 38%, and 39%.

[0065] The weight percentage of oxygen element is any value among 32%, 35%, 38%, 40%, 42%, 45%, 48%, 50%, 52%, 55%, and 58%.

[0066] According to one embodiment of the present application, in the second material layer 12, the weight percentage of the magnesium element is greater than or equal to 1% and less than or equal to 15%, the weight percentage of the aluminum element is greater than or equal to 10% and less than or equal to 25%, the weight percentage of the silicon element is greater than or equal to 10% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%.

[0067] In this embodiment, the second material layer 12 contains magnesium, aluminum, silicon and oxygen elements, wherein the weight percentage of the magnesium element is greater than or equal to 1% and less than or equal to 15%, the weight percentage of the aluminum element is greater than or equal to 10% and less than or equal to 25%, the weight percentage of the silicon element is greater than or equal to 10% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%, so that the second material layer 12 can synthesize a crystalline phase with a low expansion coefficient, and at the same time can also form aluminum oxide through the aluminum and oxygen elements, thereby improving the bonding force between the first material layer 10 and the second material layer 12.

[0068] In specific applications, the weight percentage of magnesium element is any value among 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, and 14%.

[0069] The weight percentage of aluminum element is any value among 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, and 24%.

[0070] The weight percentage of silicon element is any value among 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, and 44%.

[0071] The weight percentage of oxygen element is any value among 32%, 35%, 38%, 40%, 42%, 45%, 48%, 50%, 52%, 55%, and 58%.

[0072] According to one embodiment of the present application, the thickness of the first material layer 10 is greater than or equal to 50 μm and less than or equal to 500 μm; the porosity of the first material layer 10 is less than or equal to 1%; the expansion coefficient of the first material layer 10 in a preset temperature range is greater than or equal to 0×10 -6 / K, and less than or equal to 1.5×10 -6 / K.

[0073] In this embodiment, if the first material layer 10 is too thick, the manufacturing cost will increase and a large stress difference will be generated, which may easily cause the first material layer 10 to crack. If the thickness of the first material layer 10 is too small, the panel 1 will be insufficiently strong, which may easily cause the first material layer 10 to crack when subjected to mechanical impact. Therefore, the thickness of the first material layer 10 is set between 50μm and 500μm to ensure the strength of the first material layer 10. The porosity of the first material layer 10 is less than or equal to 1%, which can prevent liquid from entering the second material layer 12 through the first material layer 10 and then entering the internal components through the second material layer 12 to cause leakage. When the preset temperature range of the first material layer 10 is room temperature to 1000℃, the expansion coefficient of the first material layer 10 is greater than or equal to 0×10 -6 / K, and less than or equal to 1.5×10 -6 / K, so that the first material layer 10 has a lower expansion coefficient, so that when the panel 1 is heated at a high temperature, the first material layer 10 can be prevented from cracking.

[0074] In a specific application, the thickness of the first material layer 10 is any value among 320 μm, 350 μm, 380 μm, 400 μm, 420 μm, 450 μm, and 480 μm.

[0075] The porosity of the first material layer 10 is any value among 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, and 0.9%.

[0076] The expansion coefficient of the first material layer 10 is 0.2×10-6 / K, 0.5×10 -6 / K, 0.8×10 -6 / K, 1×10 -6 / K, 1.2×10 -6 / K, 1.5×10 -6 Any value in / K.

[0077] The room temperature is greater than or equal to 10°C and less than or equal to 30°C.

[0078] According to one embodiment of the present application, the thickness of the second material layer 12 is greater than or equal to 5 mm and less than or equal to 10 mm; the porosity of the second material layer 12 is greater than or equal to 10% and less than or equal to 25%; the expansion coefficient of the second material layer 12 in a preset temperature range is greater than or equal to 1.5×10 -6 / K, and less than or equal to 3.5×10 -6 / K.

[0079] In this embodiment, if the thickness of the second material layer 12 is too thick, the thickness of the panel 1 will be too thick, the material will be too much, and the cost will be too high. If the thickness of the second material layer 12 is too small, the strength will be too low and the mechanical impact requirements will not be met. Therefore, the thickness of the second material layer 12 is set between 5mm and 10mm, which not only ensures the strength of the panel 1 but also reduces the manufacturing cost. The porosity of the second material layer 12 is between 10% and 25%, which not only satisfies the offsetting effect of the second material layer 12 on the thermal expansion of the internal particles, but also ensures the strength of the panel 1. The expansion coefficient of the second material layer 12 in the preset temperature range is greater than or equal to 1.5×10 -6 / K, and less than or equal to 3.5×10 -6 / K, so that the second material layer 12 has a lower expansion coefficient, thereby preventing the panel 1 from cracking when heated at high temperature.

[0080] Specifically, the preset temperature range is from room temperature to 1000° C. Further, the room temperature is greater than or equal to 10° C. and less than or equal to 30° C.

[0081] In a specific application, the thickness of the second material layer 12 is any value among 6 mm, 7 mm, 8 mm, 9 mm, and 9.5 mm.

[0082] The porosity of the second material layer 12 is any value among 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, and 24%.

[0083] The expansion coefficient of the second material layer 12 is 1.6×10 -6 / K, 1.7×10 -6 / K, 1.8×10 -6 / K, 1.9×10 -6 / K, 2×10 -6 / K, 2.2×10 -6 / K, 2.5×10 -6 / K, 2.6×10 -6 / K, 2.8×10 -6 / K, 3×10 -6 / K, 3.2×10 -6 / K, 3.5×10 -6 Any value in / K.

[0084] According to one embodiment of the present application, the ratio of the thickness of the second material layer 12 to the thickness of the first material layer 10 is greater than or equal to 10 and less than or equal to 200.

[0085] In this embodiment, the ratio of the thickness of the second material layer 12 to the thickness of the first material layer 10 is between 10 and 200, which can ensure the strength of the panel 1 and meet the mechanical impact requirements.

[0086] In a specific application, the thickness of the first material layer 10 is greater than or equal to 50 micrometers and less than or equal to 500 micrometers.

[0087] According to one embodiment of the present application, the panel 1 further includes: a waterproof layer, which is provided on a side of the first material layer 10 facing away from the second material layer 12 .

[0088] In this embodiment, a waterproof layer is provided on the side of the first material layer 10 facing away from the second material layer 12. The waterproof layer has a waterproof effect and can further prevent liquid from flowing into the components below through the second material layer 12, thereby avoiding leakage.

[0089] In specific applications, the waterproof layer needs to meet the requirements of low expansion coefficient, low porosity and good bonding strength with the first material layer 10 .

[0090] According to one embodiment of the present application, the first material layer 10 and the second material layer 12 are an integral sintered structure.

[0091] In this embodiment, the first material layer 10 and the second material layer 12 are integrally sintered, so that atomic diffusion occurs between particles, forming sintered necks, thereby improving the mechanical strength of the panel 1. Furthermore, the first material layer 10 can be sintered to form a structure with a lower density.

[0092] It can be understood that the panel 1 is a ceramic panel.

[0093] According to one embodiment of the present invention, an electrical appliance is provided, comprising: a panel 1 as provided in any of the above embodiments.

[0094] The electrical appliance provided by the present invention comprises the panel 1 proposed in any of the above embodiments, and therefore has all the beneficial effects of the panel 1.

[0095] It should be noted that electrical appliances include kitchen appliances, and further, electrical appliances include induction cookers, multi-burner stoves, etc.

[0096] In specific applications, the panel 1 proposed in this application first selects a ceramic system with a low expansion coefficient, and secondly introduces gaps between the ceramic grains. When the ceramic plate expands due to heat, the ceramic particles will expand microscopically. At this time, the gaps between the particles can offset the volume expansion caused by the thermal expansion of the particles, and macroscopically avoid the ceramic panel from cracking when heated at high temperatures. Finally, in the use scenario of an induction cooker, the presence of pores in the panel 1 will cause water to penetrate into the electronic components under the panel 1, thereby causing safety risks. Therefore, a waterproof layer is added to the surface of the panel 1. The waterproof layer is made of a waterproof material. This material must meet the requirements of low expansion coefficient, low porosity and good bonding with the substrate.

[0097] Specifically, if Figure 1 and Figure 2 As shown, the panel 1 includes a first material layer 10 located on the surface and a second material layer 12 located on the bottom. The bottom material contains a Mg-Al-Si-O (manganese-silicon-aluminum-oxygen) phase with a low expansion coefficient of 1.5×10 -6 / K~3.5×10 -6 / K is the basic requirement for panel 1 to withstand thermal shock. At the same time, to further enhance the material's thermal shock resistance, solid-state sintering is used to cause atomic diffusion between the particles to form sintering necks, thereby enhancing the mechanical strength of the ceramic plate. Since solid-state sintering does not cause significant material shrinkage, the overall shrinkage of panel 1 from the pressed green body to the sintered form is no more than 5%. However, due to the densification solid-state sintering between the ceramic particles, a large number of gaps exist between the particles, with a porosity of between 10% and 25%. These gaps can offset the volume expansion caused by thermal expansion of the particles, and macroscopically prevent panel 1 from cracking when heated at high temperatures. In addition, the strength of panel 1 is inversely proportional to the porosity, so the thickness of the underlying material must be greater than 5mm to meet the mechanical shock requirements. At the same time, if the thickness of the underlying material is greater than 10mm, although the strength requirements are met, the material weight is too large and the cost is too high.

[0098] The induction cooker or multi-burner stove top 1 is primarily used for cooking, so its surface is often in contact with water. To prevent water from seeping into the bottom of the panel 1 and causing leakage of electronic components, the ceramic plate surface is required to have extremely low porosity. However, this poses two problems:

[0099] (1) Since the surface and bottom materials are sintered together, but at the same sintering temperature, the surface material is denser than the bottom material, so the surface material components are required to be easier to densify and sinter.

[0100] (2) The thermal expansion coefficients of the surface and bottom materials should match to avoid cracking between the surface and bottom layers during heating. Since the surface material is much denser than the bottom material, it cannot rely on pores to resist thermal stress. Therefore, the thermal expansion coefficient of the surface material is required to be lower than that of the bottom layer.

[0101] Furthermore, we add 0.1% to 5% Li to the surface material, which has two effects:

[0102] (1) Li forms Li2O during sintering, which is an alkali metal oxide flux. During high-temperature sintering, it forms a liquid glass phase, filling the gaps between particles, promoting ceramic densification and sintering, and causing the surface material to shrink significantly. However, due to the low sintering shrinkage rate of the underlying material, surface compressive stress is formed when the surface material shrinks, while thermal shock is mainly tensile stress, which can further mitigate cracking caused by thermal stress during the thermal shock process.

[0103] (2) During the sintering process, Li forms a Li-Al-Si-O (lithium-aluminum-silicon-oxygen) crystal phase with three elements, Al (aluminum), Si (silicon), and O (oxygen), which has a negative thermal expansion coefficient and can significantly reduce the overall thermal expansion coefficient of the surface material (0×10 -6 / K~1.5×10 -6 / K).

[0104] Furthermore, the thickness of the surface layer is 50 microns to 500 microns: when the surface layer thickness is less than 50 microns, insufficient strength causes surface cracking due to mechanical impact; when the surface layer thickness is greater than 500 microns, a large stress difference is generated when the surface material and the underlying material are sintered together, causing surface cracking.

[0105] Furthermore, both the bottom layer and the surface layer materials contain more than 10% Si and more than 30% O, which can form Si-O-Si chemical bonds during sintering, thereby improving the bonding strength between the bottom layer and the surface layer.

[0106] This application was tested on Example 1 and Comparative Examples 1 to 6, and the testing method was as follows:

[0107] 1. Porosity: Because the base and surface materials are tightly bonded, it is difficult to remove the two layers separately. Therefore, the porosity is calculated using a microscopic image method. The sample cross-section is directly observed using a scanning electron microscope. Parallel cross-section photographs of the sample are taken sequentially at an appropriate magnification (only the base or surface material is in the field of view). Using image processing software such as ImageJ, the different contrasts between the pores and the substrate are used to identify the proportion of pores in the entire image. Repeat the process for 5 images, and the final average value is used as the porosity of the sample.

[0108] 2. Mechanical shock: Use a 0.5J spring impact gun to impact the center and four corners of panel 1, a total of five locations, three times each. The ceramic plate should not crack or break.

[0109] 3. Hot and cold shock: Place the ceramic panel in a constant temperature box at 550℃. After reaching thermal equilibrium, take it out and quickly put it into water at 25℃±5℃. There should be no paint falling off, and the ceramic panel should not crack or break.

[0110] The parameters of Example 1 and Comparative Examples 1 to 6 are as follows:

[0111] Example 1: The surface layer of the ceramic panel has a thickness of 385 microns and a porosity of 0.52%; the bottom layer has a thickness of 6 mm and a porosity of 14.8%.

[0112] Comparative Example 1: The surface layer of the ceramic panel has a thickness of 40 microns and a porosity of 0.52%; the bottom layer has a thickness of 6 mm and a porosity of 14.8%.

[0113] Comparative Example 2: The surface layer of the ceramic panel has a thickness of 530 microns and a porosity of 0.52%; the bottom layer has a thickness of 6 mm and a porosity of 14.8%.

[0114] Comparative Example 3: The surface layer of the ceramic panel has a thickness of 385 microns and a porosity of 1.5%; the bottom layer has a thickness of 6 mm and a porosity of 14.8%.

[0115] Comparative Example 4: The surface layer of the ceramic panel has a thickness of 385 microns and a porosity of 0.52%; the bottom layer has a thickness of 4.5 mm and a porosity of 14.8%.

[0116] Comparative Example 5: The surface layer of the ceramic panel has a thickness of 385 microns and a porosity of 0.52%; the bottom layer has a thickness of 6 mm and a porosity of 8.5%.

[0117] Comparative Example 6: The surface layer of the ceramic panel has a thickness of 385 microns and a porosity of 0.52%; the bottom layer has a thickness of 6 mm and a porosity of 28%.

[0118] Table 1: Test results of different embodiments and comparative examples

[0119]

[0120]

[0121] Specifically, OK in Table 1 indicates that the test passed, and NG indicates that the test failed.

[0122] As shown in Example 1 and Comparative Example 1, ceramic panels with a surface layer thickness less than 50 microns lack mechanical resistance and cracking. As shown in Example 1 and Comparative Example 2, ceramic panels with a surface layer thickness greater than 500 microns experience cracking after sintering due to the significant stress difference between the surface layer and the underlying material caused by differences in expansion coefficients. As shown in Example 1 and Comparative Example 3, ceramic panels with excessive surface porosity can lead to water seepage, potentially causing a safety hazard of short-circuiting electronic components beneath the panel. As shown in Example 1 and Comparative Example 4, ceramic panels with a bottom layer thickness less than 5 mm exhibit insufficient strength and cracking under mechanical impact. As shown in Example 1 and Comparative Example 5, ceramic panels with a bottom layer porosity less than 10% experience cracking after thermal shock, indicating insufficient intergranular clearance between the bottom layers to offset the stress generated by thermal expansion. As shown in Example 1 and Comparative Example 6, ceramic panels with a bottom layer porosity greater than 25% experience cracking under mechanical impact. This is because the strength and porosity of ceramic panels are inversely proportional; excessive porosity reduces the strength of the panel.

[0123] In summary, the best solution is: the ceramic panel has a double-layer structure, the surface layer is 50 microns to 500 microns, the porosity is less than 1%, and the expansion coefficient is 0×10 -6 / K~1.5×10 -6 / K; the thickness of the bottom material is greater than 5mm, the porosity is 10% to 25%, and the expansion coefficient is 1.5×10 -6 / K~3.5×10 -6 / K, further the thickness of the underlying material is less than 10 mm.

[0124] In the present invention, the term "plurality" refers to two or more, unless otherwise specified. Terms such as "mounted," "connected," "connected," and "fixed" should be interpreted broadly. For example, "connected" can refer to fixed, removable, or integral connections; and "connected" can refer to direct or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0125] Throughout this specification, terms such as "one embodiment," "some embodiments," and "specific embodiments" mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0126] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A panel, wherein the panel is a ceramic panel, characterized in that: include: a first material layer; a second material layer disposed on one side of the first material layer, wherein the density of the first material layer is greater than that of the second material layer, and the porosity of the first material layer is lower than that of the second material layer; The thickness of the first material layer is greater than or equal to 50 μm and less than or equal to 500 μm; The porosity of the first material layer is less than or equal to 1%; the expansion coefficient of the first material layer in a preset temperature range is greater than or equal to 0×10 -6 / K, and less than or equal to 1.5×10 -6 / K; The thickness of the second material layer is greater than or equal to 5 mm and less than or equal to 10 mm; The porosity of the second material layer is greater than or equal to 10% and less than or equal to 25%; the expansion coefficient of the second material layer in a preset temperature range is greater than or equal to 1.5×10 -6 / K, and less than or equal to 3.5×10 -6 / K; Wherein, the preset temperature range is from room temperature to 1000°C.

2. The panel according to claim 1, wherein The expansion coefficient of the first material layer is lower than the expansion coefficient of the second material layer, Wherein, the crystal phase of the first material layer includes a negative expansion crystal phase.

3. The panel according to claim 1, wherein The first material layer and the second material layer both contain silicon and oxygen. The weight percentage of the silicon is greater than or equal to 10%, and the weight percentage of the oxygen is greater than or equal to 30%.

4. The panel according to claim 3, characterized in that The first material layer further includes lithium and / or magnesium, and the second material layer further includes magnesium.

5. The panel according to claim 4, characterized in that The crystal phase of the first material layer includes a lithium-aluminum-silicon-oxygen crystal phase, and the crystal phase of the second material layer includes a magnesium-aluminum-silicon-oxygen crystal phase.

6. The panel according to claim 5, characterized in that In the first material layer, the weight percentage of the lithium element is greater than 0% and less than or equal to 5%, the weight percentage of the magnesium element is greater than or equal to 0% and less than or equal to 8%, the weight percentage of the aluminum element is greater than or equal to 5% and less than or equal to 15%, the weight percentage of the silicon element is greater than or equal to 20% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%.

7. The panel according to claim 5, characterized in that In the second material layer, the weight percentage of the magnesium element is greater than or equal to 1% and less than or equal to 15%, the weight percentage of the aluminum element is greater than or equal to 10% and less than or equal to 25%, the weight percentage of the silicon element is greater than or equal to 10% and less than or equal to 45%, and the weight percentage of the oxygen element is greater than or equal to 30% and less than or equal to 60%.

8. The panel according to any one of claims 1 to 7, characterized in that The ratio of the thickness of the second material layer to the thickness of the first material layer is greater than or equal to 10 and less than or equal to 200.

9. The panel according to any one of claims 1 to 7, characterized in that Also includes: The waterproof layer is arranged on a side of the first material layer facing away from the second material layer.

10. The panel according to any one of claims 1 to 7, characterized in that The first material layer and the second material layer are an integral sintered structure.

11. An electrical appliance, characterized in that: include: A panel as claimed in any one of claims 1 to 10.

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