A multi-layer structure material, its preparation method and application

Abstract

The present invention discloses a multi-layer structure material, a preparation method thereof and an application, belonging to the technical field of fireproof and radiation-proof materials. The multi-layer structure material of the present invention includes an organic conductive coating, an aluminum foil layer, an adhesive layer and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer. Preparing this material into a fireproof and radiation-proof protective shell of a microwave heater can effectively protect against the electromagnetic wave radiation generated by microwave heating and the resulting fires or even explosions, and improve the safety of the microwave heater during use.

Description

Technical Field

[0001] The present invention belongs to the technical field of fireproof and radiation-proof materials, and particularly relates to a multi-layer structure material, a preparation method thereof and an application thereof. Background Art

[0002] Silicon nitride ceramic substrates are advanced engineering ceramic plates with high strength, fracture toughness, hardness, wear resistance and good chemical and thermal stability, and can be processed into composite material plates to be used as protection devices for industrial equipment.

[0003] In today's society, more and more industrial instruments need to be heated by microwaves. Microwave heating has the advantages of high-speed and uniform heating, resource conservation, high efficiency, easy control and sustainability, and labor saving. However, problems such as radiation and fire and explosion caused by microwave heating are becoming increasingly prominent. Radiation can have an adverse impact on human health, and fires or even explosions can cause losses to the outside world. At present, most of the relevant patent literatures at home and abroad only focus on the methods and equipment of microwave heating; therefore, eliminating electromagnetic radiation and preventing fires and disasters are urgent problems to be solved. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide a multi-layer structure material with fireproof and radiation-proof functions, a preparation method thereof and an application thereof.

[0005] In order to achieve the above purpose, the following technical solutions are adopted:

[0006] A multi-layer structure material, comprising an organic conductive coating, an aluminum foil layer, an adhesive layer and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer;

[0007] The thickness of the silicon nitride ceramic substrate layer is 0.5 - 3 mm;

[0008] The thickness of the aluminum foil layer is 0.1 mm to 1 mm;

[0009] The surface density of the adhesive layer is 100 - 150 g / m 2 ;

[0010] The organic conductive coating is composed of epoxy resin E51, filler, triethylenetetramine and butyl acetate, and the mass fraction ratio is 100:(15 - 20):(25 - 30):(25 - 30).

[0011] In a specific embodiment, the performance parameters of the silicon nitride ceramic substrate layer are strength (MPa) 600 - 700, fracture toughness (MPa·m 1 / 2)6.0 - 7.0, thermal conductivity (W / (m·K)) ≥ 90, current carrying capacity (A) ≥ 300, thermal resistance (℃ / W) ≤ 0.5, reliability (℃ / W) ≥ 5000.

[0012] In a specific embodiment, the silicon nitride ceramic substrate layer is prepared by a tape casting process or a sintering reaction and resintering method.

[0013] In a specific embodiment, the adhesive is selected from epoxy resin adhesives.

[0014] The preparation method of the above multi-layer structural material is as follows:

[0015] (1) Bonding of the silicon nitride ceramic substrate layer:

[0016] Take the silicon nitride ceramic substrate layer and bond an aluminum foil layer on the bottom surface of the substrate using an adhesive.

[0017] (2) Preparation of the organic conductive coating:

[0018] Mix epoxy resin E51, filler, curing agent triethylenetetramine, and butyl acetate evenly to make a conductive coating. Apply the coating on the surface after sealing holes by a coating process and react at room temperature for 48 h to form an organic conductive coating, thus obtaining the multi-layer structural material.

[0019] Application of the multi-layer structural material prepared by the above method in fire and radiation protection.

[0020] A fire and radiation protection shell for a microwave heater, using the above multi-layer structural material.

[0021] In a specific embodiment, the fire and radiation protection shell of the microwave heater includes a housing 1 and a radiator 2 provided on the housing 1; the housing 1 from the inside to the outside is successively an organic conductive coating 1-1, an aluminum foil layer 1-2, an adhesive layer 1-3, and a silicon nitride ceramic substrate layer 1-4.

[0022] Advantages of the technical solution of the present invention:

[0023] The multi-layer structural material prepared by the method of the present invention has excellent fire and radiation protection performance. Preparing the material into a fire and radiation protection shell for a microwave heater can effectively protect against electromagnetic wave radiation generated by microwave heating and fires or even explosions caused, improving the safety of the microwave heater during use. Secondly, the preparation process is mature, the thickness of the aluminum foil is 0.1 mm, the cost is controllable, and the overall cost of the protection shell material does not increase significantly. In addition, when the temperature inside the microwave heater is too high, the over-temperature alarm will give a prompt to remind the surrounding people to pay attention to this situation. Brief Description of the Drawings

[0024] Figure 1Schematic structural diagram of the fire and radiation protection shell of the microwave heater in Example 14;

[0025] Figure 2 It is Figure 1 The enlarged structural diagram of part A in Detailed implementation manners

[0026] Other terms used in the present invention, unless otherwise specified, generally have the meanings commonly understood by those of ordinary skill in the art.

[0027] The present invention will be further described in detail below with reference to specific examples and data. The following examples are only for illustrating the present invention and do not limit the scope of the present invention in any way.

[0028] Example 1

[0029] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0030] The thickness of the silicon nitride ceramic substrate layer is 0.7 mm; it can be prepared by a tape casting process or a sintering reaction re-sintering method, and its performance parameters are: strength (MPa) 600 - 700, fracture toughness (MPa·m 1 / 2 ) 6.0 - 7.0, thermal conductivity (W / (m·K)) ≥ 90, current carrying capacity (A) ≥ 300, thermal resistance (℃ / W) ≤ 0.5, reliability (℃ / W) ≥ 5000.

[0031] The thickness of the aluminum foil layer is 0.1 mm;

[0032] The areal density of the adhesive layer is 120 g / m 2 ; The adhesive is selected from epoxy resin adhesives;

[0033] The organic conductive coating is composed of epoxy resin E51, filler, triethylenetetramine, and butyl acetate, and the mass fraction ratio is 100:(15 - 20):(25 - 30):(25 - 30);

[0034] The preparation method of the multi-layer structural material is as follows:

[0035] (1) Bonding of the silicon nitride ceramic substrate layer:

[0036] Select the silicon nitride ceramic substrate layer, and bond an aluminum foil layer on the bottom surface of the substrate using the adhesive.

[0037] (2) Preparation of the organic conductive coating:

[0038] The epoxy resin E51, filler, curing agent triethylenetetramine, and butyl acetate were mixed evenly to form a conductive coating. The coating was applied to the surface after sealing holes by a coating process and reacted at room temperature for 48 h to form an organic conductive coating, thus obtaining a multi-layer structural material.

[0039] In the above multi-layer structural material, the organic conductive coating shields electromagnetic waves by absorbing, conducting, and weakening electromagnetic waves; the aluminum foil layer has excellent electrical conductivity. When aluminum encounters electromagnetic waves, reflection occurs. Adding a conductive coating on the surface of the aluminum foil layer will have a better effect and can resist the radiation of high-frequency electromagnetic waves. Silicon nitride ceramic substrate layer: It has high hardness, inherent lubricity, wear resistance, atomic crystallinity, and oxidation resistance at high temperatures. It can effectively prevent fires or explosions caused by microwave heating. The role of the adhesive layer is to bond the aluminum foil layer to the silicon nitride ceramic substrate layer. Therefore, with the cooperation of the above multi-layers, the prepared multi-layer structural material has the functions of fire prevention and radiation protection.

[0040] Example 2

[0041] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is applied on the outer surface of the aluminum foil layer.

[0042] The thickness of the silicon nitride ceramic substrate layer is 1.5 mm;

[0043] The thickness of the aluminum foil layer is 0.1 mm;

[0044] Other parameters and preparation methods are the same as those in Example 1.

[0045] Example 3

[0046] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is applied on the outer surface of the aluminum foil layer.

[0047] The thickness of the silicon nitride ceramic substrate layer is 2 mm;

[0048] The thickness of the aluminum foil layer is 0.2 mm;

[0049] Other parameters and preparation methods are the same as those in Example 1.

[0050] Example 4

[0051] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is applied on the outer surface of the aluminum foil layer.

[0052] The thickness of the silicon nitride ceramic substrate layer is 1.3 mm;

[0053] The thickness of the aluminum foil layer is 0.3 mm;

[0054] Other parameters and preparation methods are the same as those in Example 1.

[0055] Example 5

[0056] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0057] The thickness of the silicon nitride ceramic substrate layer is 2.5 mm;

[0058] The thickness of the aluminum foil layer is 0.3 mm;

[0059] Other parameters and preparation methods are the same as those in Example 1.

[0060] Example 6

[0061] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0062] The thickness of the silicon nitride ceramic substrate layer is 1 mm;

[0063] The thickness of the aluminum foil layer is 0.5 mm;

[0064] Other parameters and preparation methods are the same as those in Example 1.

[0065] Example 7

[0066] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0067] The thickness of the silicon nitride ceramic substrate layer is 1.8 mm;

[0068] The thickness of the aluminum foil layer is 0.5 mm;

[0069] Other parameters and preparation methods are the same as those in Example 1.

[0070] Example 8

[0071] A multi-layer structural material, comprising an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0072] The thickness of the silicon nitride ceramic substrate layer is 2.7 mm;

[0073] The thickness of the aluminum foil layer is 0.6 mm;

[0074] Other parameters and preparation methods are the same as those in Example 1.

[0075] Example 9

[0076] A multi-layer structural material, comprising an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0077] The thickness of the silicon nitride ceramic substrate layer is 2.8 mm;

[0078] The thickness of the aluminum foil layer is 0.7 mm;

[0079] Other parameters and preparation methods are the same as those in Example 1.

[0080] Example 10

[0081] A multi-layer structural material, comprising an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0082] The thickness of the silicon nitride ceramic substrate layer is 0.8 mm;

[0083] The thickness of the aluminum foil layer is 0.8 mm;

[0084] Other parameters and preparation methods are the same as those in Example 1.

[0085] Example 11

[0086] A multi-layer structural material, comprising an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0087] The thickness of the silicon nitride ceramic substrate layer is 2.2 mm;

[0088] The thickness of the aluminum foil layer is 0.8 mm;

[0089] Other parameters and preparation methods are the same as those in Example 1.

[0090] Example 12

[0091] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0092] The thickness of the silicon nitride ceramic substrate layer is 1.8 mm;

[0093] The thickness of the aluminum foil layer is 1 mm;

[0094] Other parameters and preparation methods are the same as those in Example 1.

[0095] Example 13

[0096] A multi-layer structural material includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is bonded to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer.

[0097] The thickness of the silicon nitride ceramic substrate layer is 2.5 mm;

[0098] The thickness of the aluminum foil layer is 1 mm;

[0099] Other parameters and preparation methods are the same as those in Example 1.

[0100] The refractoriness and signal reflectivity of the multi-layer structural materials prepared by different methods in Examples 1 - 13 were measured respectively to evaluate the fire and radiation protection performance of different materials, and the results are shown in Table 1.

[0101] Among them, refractoriness: Refractoriness is a technical index. The test piece to be measured is made into a truncated triangular cone according to a certain method. The test cone is heated at a certain heating rate. When it reaches a certain temperature, a liquid phase begins to appear. As the temperature continues to rise, the liquid phase amount gradually increases and the viscosity decreases. The test cone gradually softens and bends under the action of gravity. When it bends until the vertex touches the bottom, the temperature is the refractoriness of the sample. Signal reflectivity: A C84-III type reflectivity measuring instrument is used.

[0102] Table 1 Influence of the thickness of the aluminum foil layer and the silicon nitride ceramic basic layer on the fire and radiation protection performance of the multi-layer structural material

[0103]

[0104]

[0105] As can be seen from Table 1, the multi-layer structural material prepared by the method of the present invention can effectively protect against electromagnetic radiation generated by 2G-5G signals.

[0106] Example 14

[0107] As Figure 1 and 2 shown, this embodiment provides a fire and radiation protection shell for a microwave heater, including a housing 1 and a radiator 2 provided on the housing 1; the housing 1 uses the multi-layer structural material of Examples 1-13, and the housing 1 sequentially includes an organic conductive coating 1-1, an aluminum foil layer 1-2, an adhesive layer 1-3, and a silicon nitride ceramic substrate layer 1-4 from the inside to the outside. In addition, a switch for opening the microwave heater (not shown in the figure) is provided on the housing 1; at the same time, in order to improve safety, an over-temperature alarm (not shown in the figure) is provided inside the housing 1, and when the temperature inside the housing exceeds a certain value, the over-temperature alarm will give a prompt (such as a prompt sound).

[0108] The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution content of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A multi-layer structural material, characterized in that, It includes an organic conductive coating, an aluminum foil layer, an adhesive layer, and a silicon nitride ceramic substrate layer; wherein, the aluminum foil layer is adhered to the silicon nitride ceramic substrate layer through the adhesive layer, and the organic conductive coating is coated on the outer surface of the aluminum foil layer; The thickness of the silicon nitride ceramic substrate layer is 0.5 - 3 mm; The thickness of the aluminum foil layer is 0.1 mm to 1 mm; The surface density of the adhesive is 100 to 150 g / m 2 ; The organic conductive coating is composed of epoxy resin E51, fillers, triethylenetetramine, and butyl acetate, and the mass fraction ratio is 100:(15 - 20):(25 - 30):(25 - 30); The performance parameters of the silicon nitride ceramic substrate layer are as follows: strength (MPa) 600 - 700, fracture toughness (MPa·m 1 / 2 ) 6.0 - 7.0, thermal conductivity (W / (m·K)) ≥ 90, current carrying capacity (A) ≥ 300, thermal resistance (℃ / W) ≤ 0.5, reliability (℃ / W) ≥ 5000.

2. The multi-layer structural material according to claim 1, characterized in that, The silicon nitride ceramic substrate layer is prepared by a tape casting process or a sintering reaction and re-sintering method.

3. The multi-layer structural material according to claim 1, wherein The adhesive is selected from epoxy resin adhesives.

4. The preparation method of the multi-layer structural material according to any one of claims 1-3, characterized in that, The steps are as follows: (1) Bonding of the silicon nitride ceramic substrate layer: Take the silicon nitride ceramic substrate layer and bond an aluminum foil layer on the bottom surface of the substrate using an adhesive. (2) Preparation of the organic conductive coating: Mix epoxy resin E51, fillers, the curing agent triethylenetetramine, and butyl acetate evenly to make a conductive coating. Apply the coating on the surface after sealing holes by a coating process and react at room temperature for 48 h to form an organic conductive coating, thus obtaining the multi-layer structural material.

5. Application of the multi-layer structural material prepared by the method according to claim 4 in fire prevention and radiation protection.

6. A fire and radiation protection shell for a microwave heater, characterized in that, Use the multi-layer structural material prepared by the method according to claim 4.

7. The fire and radiation protection shell of the microwave heater according to claim 6, characterized in that, It includes a housing (1) and a radiator (2) provided on the housing (1); the housing (1) is successively from the inside to the outside an organic conductive coating (1-1), an aluminum foil layer (1-2), an adhesive layer (1-3), and a silicon nitride ceramic substrate layer (1-4).

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