CN104553102A - Ultrahigh-temperature gradient heat insulation material and preparation method thereof - Google Patents

Abstract

The invention discloses an ultra-high temperature gradient heat insulation material and a preparation method thereof, wherein the ultra high temperature gradient heat insulation material comprises: an ultra high temperature heat insulation material layer located on the high temperature side; a phase change heat absorption heat insulation material layer located on the ultra high temperature side The outer side of the high temperature heat insulation layer; the medium temperature heat insulation layer is located outside the phase change heat absorption heat insulation material layer; the low temperature heat insulation layer is located outside the medium temperature heat insulation layer; the radiation shielding layer is respectively arranged on the ultra high temperature heat insulation material layer Layer, phase-change heat-absorbing and heat-insulating material layer, medium-temperature heat-insulating layer and low-temperature heat-insulating layer between two adjacent layers and outside the low-temperature heat-insulating layer, the radiation shielding layer is used to block infrared radiation; the above-mentioned layers Composite as one. The ultra-high temperature gradient thermal insulation material of the present invention has the characteristics of ultra-high temperature resistance and long service life.

Description

Ultra-high temperature gradient thermal insulation material and preparation method thereof

technical field

The invention relates to the technical field of thermal insulation materials, in particular to an ultra-high temperature gradient thermal insulation material and a preparation method thereof.

Background technique

With the rapid development of aerospace technology, thermal protection systems and materials have become one of the most important key technologies that restrict the success of aircraft research and development. With the continuous improvement of the flight Mach number, the requirements for the temperature of the thermal protection material are getting higher and higher. During operation, the temperature of the outer wall of the combustion chamber is as high as 2000K or more. In order to protect the metal shell of the engine and its surrounding electronic equipment, reduce Heat dissipation and the obvious infrared signal characteristics brought by it, the outer wall of the combustion chamber is protected by ultra-high temperature heat insulation materials.

The heat-resistant protective materials used in existing rocket engines are generally graphite cloth/phenolic, carbon cloth/phenolic, high-silica cloth/phenolic, glass cloth/phenolic, and the insulation layer material is often glass fiber, high-silica or asbestos reinforced Phenolic or epoxy resin, and asbestos or silica-filled nitrile rubber and EPDM rubber, etc. However, such heat-resistant protective materials have low temperature resistance.

With the development of aerospace technology, thermal protection materials with higher temperature resistance are gradually developed, among which ZrC/aerogel and resin polymer laminated composite materials have higher temperature resistance, but the material has long-term heat insulation performance Downsides. Zirconia-based materials are also used, but this material has the disadvantage of relatively serious radiation heat transfer at high temperatures.

It can be seen that the existing thermal protection materials have low temperature resistance, about 1800-2000K, and short service time, about tens of seconds to about 400 seconds, which can no longer meet the high Mach number and long-term flight needs of high-speed aircraft.

Contents of the invention

In view of this, an embodiment of the present invention provides an ultra-high temperature gradient thermal insulation material and a preparation method thereof, the main purpose of which is to increase the temperature resistance and prolong the use time.

In order to achieve the above object, the present invention mainly provides the following technical solutions:

On the one hand, an embodiment of the present invention provides an ultra-high temperature gradient thermal insulation material, including:

Ultra-high temperature insulation material layer, which is located on the high temperature side;

The phase-change heat-absorbing and heat-insulating material layer is located outside the ultra-high temperature heat-insulating material layer;

The medium-temperature heat-insulating layer is located outside the phase-change heat-absorbing heat-insulating material layer;

The low temperature insulation layer is located outside the medium temperature insulation layer;

The radiation shielding layer is respectively arranged between the ultra-high temperature heat insulating material layer, the phase change heat absorbing heat insulating material layer, the medium temperature heat insulating layer and the low temperature heat insulating layer and the outer side of the low temperature heat insulating layer. The radiation shield is used to block infrared radiation;

The above layers are combined into one.

Preferably, the material of the ultra-high temperature insulation material layer is carbon fiber/zirconia fiber ultra-high temperature insulation material, zirconia fiber ultra-high temperature insulation material, carbon fiber felt or ultra-fine porous carbon material.

Preferably, the material of the phase-change heat-absorbing and heat-insulating material layer is nickel fluoride high-temperature phase-change material, magnesium fluoride phase-change material or carbonate medium-temperature phase-change material.

Preferably, the material of the medium-temperature heat insulation layer is alumina fiber heat insulation material, mullite fiber heat insulation material, quartz fiber heat insulation material, calcium silicate heat insulation material or high silica fiber heat insulation material.

Preferably, the material of the low-temperature heat insulation layer is silica airgel heat insulation material, aluminum silicate fiber heat insulation material, rock wool or ultra-fine glass wool.

Preferably, the material of the radiation shielding layer is molybdenum foil, aluminum foil, graphite paper or gold foil.

Preferably, the thickness of the ultra-high temperature heat insulation material layer is 2-20mm; the thickness of the phase change heat absorption heat insulation material layer is 2-10mm; the thickness of the medium temperature heat insulation layer is 2-30mm; the low temperature The thickness of the heat insulating layer is 2-40mm; the thickness of the radiation shielding layer is 0.01-0.5mm.

Preferably, the layers are bonded with an adhesive, and then composited into one through pressure forming and high-temperature treatment.

Preferably, the adhesive is selected from aluminum phosphate-based adhesives, chromium-aluminum phosphate-based high-temperature adhesives, aluminum sol-based adhesives and silica sol-based medium-temperature adhesives.

Preferably, a high temperature adhesive is used to connect the ultra-high temperature heat insulating material layer to the phase change heat absorbing heat insulating layer; a medium temperature adhesive is used to bond the phase change heat absorbing heat insulating layer to the outermost radiation shielding layer. Knot.

On the other hand, an embodiment of the present invention provides a method for preparing any one of the above ultra-high temperature gradient heat insulation materials, including the following steps:

According to the application environment, use the heat transfer theory to determine the specific material and thickness of each insulation material layer;

According to the determined material, each insulation material layer is prepared with a corresponding thickness;

The heat insulation material layers are connected by adhesive, and then compounded into one through pressure forming and high temperature treatment to obtain an ultra-high temperature combined heat insulation material.

Preferably, the steps of compounding each thermal insulation material layer as a whole are as follows:

Apply adhesive between layers by brushing or spraying;

The pressure range of pressure forming is between 0.1MPa and 5MPa, the temperature of high temperature treatment is between 50°C and 400°C, and the treatment time is between 2h and 24h.

Compared with prior art, the beneficial effect of the present invention is:

The ultra-high temperature gradient heat insulation material of the embodiment of the present invention has a temperature resistance of 2300-2500K. The protective use time can reach 2500 seconds. The production cycle of the invention is short, and material selection, preparation and molding can be completed in about 2 to 3 weeks. The ultra-high temperature gradient thermal insulation material of the embodiment of the present invention has a wider selection range of raw materials under ultra-high temperature conditions.

Description of drawings

Fig. 1 is a schematic structural diagram of an ultra-high temperature gradient thermal insulation material according to an embodiment of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments, but not as a limitation of the present invention. In the following description, different "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

Fig. 1 is a schematic structural diagram of an ultra-high temperature gradient thermal insulation material according to an embodiment of the present invention. As shown in Figure 1, the ultra-high temperature gradient heat insulation material has the following structure:

Ultra-high temperature insulation material layer 1, which is located on the high temperature side;

The phase-change heat-absorbing and heat-insulating material layer 2 is located outside the ultra-high-temperature heat-insulating material layer 1;

The medium-temperature heat-insulation layer 3 is located outside the phase-change heat-absorbing heat-insulation material layer 2;

The low temperature heat insulation layer 4 is located outside the medium temperature heat insulation layer 3;

The radiation shielding layer 5 is respectively arranged between two adjacent layers of the ultra-high temperature heat insulating material layer 1, the phase change heat absorbing heat insulating material layer 2, the medium temperature heat insulating layer 3 and the low temperature heat insulating layer 4, and the low temperature heat insulating layer On the outside of layer 4, radiation shielding layer 5 is used to block infrared radiation;

The above layers are combined into one.

The ultra-high temperature composite heat insulation material of the embodiment of the present invention considers the requirement of blocking the internal high temperature higher than 2200°C to the outer surface temperature of low temperature, and the side contacting the high temperature end is set as an ultra-high temperature insulation material capable of withstanding the high temperature of 2200°C. The thermal material layer enables the temperature on the outside to drop below 1000°C. By arranging a phase-change heat-absorbing and heat-insulating material layer outside the ultra-high-temperature heat-insulating material layer, the temperature is rapidly lowered, and then setting a lower temperature-resistant heat-insulating material layer can realize the heat-insulating effect on ultra-high temperature. And the infrared radiation is effectively blocked by setting the radiation shielding layer. In the embodiment of the present invention, multiple thermal insulation material layers are combined to form a new thermal insulation material. Through the different temperature resistance and thermal conductivity of each layer, it can achieve high temperature resistance and low average thermal conductivity as a whole. Meet the overall heat insulation requirements. Among them, the temperature resistance of the ultra-high temperature heat insulation material layer can reach 3000 °C; the temperature resistance of the phase change heat absorption heat insulation material layer is below 2000 °C; the temperature resistance of the medium temperature heat insulation layer is below 2000 °C; the temperature resistance of the low temperature heat insulation layer is 1400 °C the following. Like this, the thermal insulation material layer of outer layer just has more selectivity.

Example 1

According to the application environment, use the heat transfer theory to determine the specific material and thickness of each heat insulation material layer; prepare each heat insulation material layer with a corresponding thickness according to the determined material; connect each heat insulation material layer with an adhesive to obtain a super high temperature Combined insulation.

The material and thickness of each layer of the ultra-high temperature composite heat insulation material determined through the above steps are as follows: the material used for the ultra-high temperature heat insulation material layer is carbon fiber/zirconia fiber ultra-high temperature heat insulation material with a thickness of 2mm; phase change heat absorption and heat insulation The material layer is made of magnesium fluoride phase-change material with a thickness of 2mm; the material used for the medium temperature insulation layer is alumina fiber insulation material with a thickness of 10mm; the material used for the low temperature insulation layer is silica airgel insulation material with a thickness of 15mm; the radiation shielding layer is made of molybdenum foil with a thickness of 0.02mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Aluminum sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer. The binder is applied by brushing or spraying. The material is compounded by pressure and high-temperature treatment process, and then press-formed under a pressure of 0.1MPa-5MPa. After forming, high-temperature treatment is carried out at a temperature of 50°C-400°C, and the treatment time is 2h-24h.

Example 2

The difference between this embodiment and Embodiment 1 is that the materials and thicknesses used for each layer of the ultra-high temperature composite heat insulation material are as follows: the thickness of the ultra-high temperature heat insulation material layer is 2mm; the thickness of the phase change heat absorption heat insulation material layer is 10mm; The thickness of the heat insulation layer is 30mm; the material used for the low temperature heat insulation layer is aluminum silicate fiber heat insulation material with a thickness of 40mm; the material used for the radiation shielding layer is aluminum foil with a thickness of 0.01mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Silica sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 3

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is a zirconia fiber ultra-high temperature heat insulation material with a thickness of 2 mm; The heat insulation material layer is made of nickel fluoride phase change material with a thickness of 10mm; the material used for the medium temperature heat insulation layer is mullite fiber heat insulation material with a thickness of 2mm; the material used for the low temperature heat insulation layer is silica airgel heat insulation Material, the thickness is 2mm; the material used for the radiation shielding layer is gold foil, the thickness is 0.1mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Aluminum sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 4

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is a carbon fiber/zirconia fiber ultra-high temperature heat insulation material with a thickness of 10 mm; The variable heat-absorbing heat insulation layer is made of magnesium fluoride phase change material with a thickness of 8mm; the material used for the medium temperature heat insulation layer is alumina fiber heat insulation material with a thickness of 10mm; the material used for the low temperature heat insulation layer is silica airgel insulation Thermal material with a thickness of 15mm; the material used for the radiation shielding layer is molybdenum foil with a thickness of 0.025mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Aluminum sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 5

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is carbon fiber felt with a thickness of 10 mm; the phase change heat absorption heat insulation material layer is made of Carbonate phase change material with a thickness of 10mm; the material used for the medium temperature insulation layer is quartz fiber insulation material with a thickness of 10mm; the material used for the low temperature insulation layer is rock wool insulation material with a thickness of 2mm; the material used for the radiation shielding layer It is graphite paper with a thickness of 0.2mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Silica sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 6

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is an ultra-fine porous carbon material with a thickness of 10 mm; The material layer is made of magnesium fluoride phase change material with a thickness of 8mm; the material used for the medium temperature insulation layer is calcium silicate insulation material with a thickness of 5mm; the material used for the low temperature insulation layer is rock wool insulation material with a thickness of 40mm; The material used for the shielding layer is graphite paper with a thickness of 0.3mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Silica sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 7

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is carbon fiber felt with a thickness of 40 mm; the phase change heat absorption heat insulation material layer is made of Carbonate phase change material with a thickness of 10mm; the material used for the medium temperature insulation layer is high silica fiber insulation material with a thickness of 6mm; the material used for the low temperature insulation layer is ultrafine glass wool insulation material with a thickness of 20mm; The shielding layer is made of aluminum foil with a thickness of 0.03mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Aluminum sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 8

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is a zirconia fiber ultra-high temperature heat insulation material with a thickness of 10 mm; The thermal insulation material layer is made of magnesium fluoride phase change material with a thickness of 8mm; the material used for the medium-temperature thermal insulation layer is alumina fiber thermal insulation material with a thickness of 10mm; the material used for the low-temperature thermal insulation layer is aluminum silicate fiber thermal insulation material. The thickness is 20mm; the material used for the radiation shielding layer is gold foil with a thickness of 0.03mm. Each layer is bonded with aluminum phosphate high-temperature adhesive.

Example 9

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is an ultra-fine porous carbon material with a thickness of 10 mm; The material layer is made of nickel fluoride phase change material with a thickness of 10mm; the material used for the medium temperature insulation layer is calcium silicate insulation material with a thickness of 5mm; the material used for the low temperature insulation layer is silica airgel insulation material with a thickness of 20mm; the material used for the radiation shielding layer is molybdenum foil with a thickness of 0.1mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Silica sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

Example 10

The difference between this embodiment and Embodiment 1 is that the material and thickness of each layer of the ultra-high temperature composite heat insulation material are as follows: the material used for the ultra-high temperature heat insulation material layer is a zirconia fiber ultra-high temperature heat insulation material with a thickness of 10 mm; The thermal insulation material layer is made of magnesium fluoride phase change material with a thickness of 8 mm; the material used for the medium temperature thermal insulation layer is calcium silicate thermal insulation material with a thickness of 5 mm; the material used for the low temperature thermal insulation layer is rock wool thermal insulation material with a thickness of 40mm; The material used for the radiation shielding layer is graphite paper with a thickness of 0.1mm. Among them, the ultra-high temperature heat insulation material layer and the phase change heat absorption heat insulation material layer are bonded with an aluminum phosphate high-temperature adhesive, and the phase change heat absorption heat insulation layer and the medium temperature heat insulation layer, and the medium temperature heat insulation layer and the low temperature heat insulation layer are bonded together. Aluminum sol low-temperature adhesive is used to bond between the heat insulation layers and between the low temperature heat insulation layer and the radiation shielding layer.

The preparation process of each insulation material layer in the above-mentioned embodiment is as follows:

The carbon fiber/zirconia fiber ultra-high temperature heat insulation material or the zirconia fiber ultra-high temperature heat insulation material is mixed and stirred with deionized water to disperse the fibers, and then formed by suction filtration and heat treated at high temperature. It is obtained by blending ultra-fine porous carbon material fibers with sintering aids and sintering at high temperature. Carbon fiber mats are woven into blankets through carbon fibers, or organic precursors are prepared and then foamed or supercritically dried.

Preparation of phase change heat absorbing and heat insulating material layer: melting of phase change material, crushing of phase change particles obtained after smelting, blending of crushed phase change material with matrix material and reinforcing fiber, and then forming under pressure, high temperature sintering have to.

Preparation of medium-temperature insulation layer: fibers are dispersed with deionized water, formed by suction filtration, and obtained by high-temperature heat treatment, or obtained by dynamic hydrothermal synthesis of slurry, press-filtered, and dried to form.

The preparation of the low-temperature heat-insulating layer can adopt the same method as that of the medium-temperature heat-insulating layer.

In the embodiment of the present invention, the ultra-high temperature insulation material layer made of carbon fiber/zirconia fiber ultra-high temperature insulation material is a semi-rigid material with a temperature resistance of 2500°C, a density of 0.2-1.2g/cm ³ , and a thermal conductivity of 0.02- 0.2W/m·K; the ultra-high temperature insulation material layer made of zirconia fiber ultra-high temperature insulation material is a rigid material with a temperature resistance of 2500°C, a density of 0.2-1.8g/cm ³ , and a thermal conductivity of 0.02-0.2W /m·K; the ultra-high temperature insulation material layer made of carbon fiber felt is a flexible material with a temperature resistance of 3000°C, a density of 0.1-1.2g/cm ³ , and a thermal conductivity of 0.05-0.5W/m·K; ultra-fine pores The ultra-high temperature insulation material layer made of carbon material is a rigid material with a temperature resistance of 3000°C, a density of 0.1-1.2g/cm ³ , and a thermal conductivity of 0.05-0.5W/m·K. The phase change heat absorbing and insulating material layer made of magnesium fluoride phase change material, nickel fluoride phase change material and carbonate phase change material has a density of 0.2-3.0g/cm3 and a thermal conductivity of 0.05-0.5W/m ·K. The materials used for the medium temperature insulation layer are alumina fiber insulation materials, mullite fiber insulation materials, quartz fiber insulation materials, calcium silicate insulation materials and high silica fiber insulation materials, etc., which can be rigid materials or Can be a flexible material. The materials used for the low-temperature insulation layer are silica airgel insulation materials, aluminum silicate fiber insulation materials, rock wool and ultra-fine glass wool, etc., which can be rigid materials or flexible materials. Molybdenum foil, aluminum foil, graphite paper or gold foil are foil materials with a certain width, and the thickness is 0.01-0.5mm.

The performance indicators of the ultra-high temperature combined heat insulation material of the embodiment of the present invention are shown in Table 1 below. The heat insulation performance refers to GB/T17911.3-1999 test method for bulk density of refractory ceramic fiber products, and YB/T4130-2005 water flow plate method.

Table 1

It can be seen from Table 1 that the ultra-high temperature combined heat insulation material of the embodiment of the present invention has relatively high heat insulation as a whole, and by rationally setting the layer structure, the heat insulation material of the outer layer has more options. It has great advantages in terms of raw material acquisition and cost. The ultra-high temperature combined heat insulation material of the embodiment of the present invention is semi-rigid as a whole, with a density of 0.20-2.0g/cm ³ , a thermal conductivity of 0.02W/m·K-0.12W/m·K, and a maximum temperature resistance of 2200 ℃. The protective use time can reach 2500 seconds.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (12)

1. Ultra-high temperature gradient thermal insulation material, characterized in that it comprises: Ultra-high temperature insulation material layer, which is located on the high temperature side; The phase-change heat-absorbing and heat-insulating material layer is located outside the ultra-high temperature heat-insulating material layer; The medium-temperature heat-insulating layer is located outside the phase-change heat-absorbing heat-insulating material layer; The low temperature insulation layer is located outside the medium temperature insulation layer; The radiation shielding layer is respectively arranged between the ultra-high temperature heat insulating material layer, the phase change heat absorbing heat insulating material layer, the medium temperature heat insulating layer and the low temperature heat insulating layer and the outer side of the low temperature heat insulating layer. The radiation shield is used to block infrared radiation; The above layers are combined into one. 2. The ultra-high temperature gradient thermal insulation material according to claim 1, characterized in that, the material of the ultra-high temperature thermal insulation material layer is carbon fiber/zirconia fiber ultra-high temperature thermal insulation material, zirconia fiber ultra-high temperature thermal insulation material , carbon fiber felt or ultra-fine porous carbon material. 3. The ultra-high temperature gradient heat insulation material according to claim 1, characterized in that, the material of the phase change heat absorption heat insulation material layer is nickel fluoride high temperature phase change material, magnesium fluoride phase change material or carbonic acid Salt medium temperature phase change material. 4. The ultra-high temperature gradient thermal insulation material according to claim 1, characterized in that, the material of the medium temperature thermal insulation layer is alumina fiber thermal insulation material, mullite fiber thermal insulation material, quartz fiber thermal insulation material, Calcium silicate insulation material or high silica fiber insulation material. 5. The ultra-high temperature gradient thermal insulation material according to claim 1, wherein the material of the low temperature thermal insulation layer is silica airgel thermal insulation material, aluminum silicate fiber thermal insulation material, rock wool or super Fine glass wool. 6. The ultra-high temperature gradient thermal insulation material according to claim 1, characterized in that, the material of the radiation shielding layer is molybdenum foil, aluminum foil, graphite paper or gold foil. 7. The ultra-high temperature gradient thermal insulation material according to claim 1, characterized in that, the thickness of the ultra-high temperature thermal insulation material layer is 2-20mm; the thickness of the phase change heat absorption thermal insulation material layer is 2-10mm ; The thickness of the medium temperature insulation layer is 2-30mm; the thickness of the low temperature insulation layer is 2-40mm; the thickness of the radiation shielding layer is 0.01-0.5mm. 8. The ultra-high temperature gradient thermal insulation material according to claim 1, characterized in that, the layers are bonded with an adhesive, and then combined into one body through pressure forming and high temperature treatment. 9. The ultra-high temperature gradient thermal insulation material according to claim 8, wherein the adhesive is selected from the group consisting of aluminum phosphate-based adhesives, chromium-aluminum phosphate-based high-temperature adhesives, aluminum sol-based adhesives and Silica sol is a medium temperature binder. 10. The ultra-high temperature gradient heat insulation material according to claim 8, characterized in that, the phase change heat absorption heat insulation layer is connected with a high temperature adhesive; the phase change heat absorption heat insulation layer The thermal layer is bonded to the outermost radiation shielding layer with a medium-temperature adhesive. 11. The preparation method of the ultra-high temperature composite heat insulation material described in any one of claims 1-10, comprising the following steps: According to the application environment, use the heat transfer theory to determine the specific material and thickness of each insulation material layer; According to the determined material, each insulation material layer is prepared with a corresponding thickness; The thermal insulation material layers are bonded with an adhesive, and then combined into one through pressure forming and high-temperature treatment to obtain an ultra-high temperature gradient thermal insulation material. 12. The preparation method according to claim 11, characterized in that, the step of compounding each insulation material layer as a whole is as follows: Apply adhesive between layers by brushing or spraying; The pressure range of pressure forming is between 0.1MPa and 5MPa, the temperature of high temperature treatment is between 50°C and 400°C, and the treatment time is between 2h and 24h.