Room-temperature curing phosphate high-temperature-resistant material and preparation method thereof

Abstract

The invention relates to a room-temperature curing phosphate high-temperature-resistant material and a preparation method thereof, the material is formed by combining two component substances, the component I is a mixed inorganic phosphate hydrated adhesive mixture, the component II is a solid mixture composed of a curing agent and a functional filler, and the mass ratio of the component I to the component II is # imgabs 0 # imgabs 1 # during preparation, and the mass ratio of the component I to the component II is 1 # imgabs 0 # imgabs 1 #. The preparation method comprises the following steps: grinding and uniformly mixing the component I and the component II, pouring into a block, bonding ceramic materials in a high-temperature environment, preventing bubbles from being generated in the pouring process, ensuring that the vibration frequency is 20-50Hz and the vibration amplitude is not less than 0.4 mm in the pouring process, curing the material at room temperature, and having excellent high-temperature resistance, water resistance and bonding performance; and meanwhile, the preparation and forming processes are simple, and the like.

Description

Technical Field

[0001] The invention discloses a room temperature curing phosphate high temperature resistant material and a preparation method thereof, belonging to the technical field of inorganic high temperature resistant materials. Background Art

[0002] Phosphate composite materials have the characteristics of high temperature resistance, high strength, excellent dielectric properties, oxidation resistance, good structural designability, and small thermal expansion coefficient. It concentrates the advantages of metals and ceramics and is an ideal material for high temperature resistance. At the same time, the material system also has the characteristics of low cost and simple molding process. This material is a high temperature resistant material used in space shuttles, and is also used in the bonding of high temperature parts of aircraft engines and refractory bricks.

[0003] There are five main types of phosphate systems: (1) Magnesium phosphates, which are usually prepared by the reaction of orthophosphate and magnesium oxide or magnesium hydroxide. This type of material has good metal bonding adaptability, but poor high temperature resistance, is easily deformed above 1200°C, and has low bonding strength; (2) Zirconium phosphates, which are usually prepared by the reaction of zirconium hydroxide and orthophosphate. This phosphate has moderate reactivity and good temperature resistance, but is not suitable for long-term storage; (3) Aluminum phosphates, which are usually prepared by the reaction of orthophosphate and aluminum oxide or aluminum hydroxide. It has the advantages of strong adhesion, high reactivity and good high temperature resistance, but poor water resistance; (4) Chromium phosphates, which are usually prepared by the reaction of chromic anhydride and orthophosphate. The trivalent chromium ions in this type of material are toxic, so this type of material is less used; (5) Aluminum chromium phosphates, which are usually prepared by the reaction of aluminum phosphate and chromium oxide in formaldehyde solution. This type of material has good stability in water, but the curing temperature is high and needs to be heated to 200°C to cure. Summary of the invention

[0004] The present invention is designed to address the above-mentioned existing technical conditions and provides a room temperature curing phosphate high temperature resistant material and a preparation method thereof, the purpose of which is to meet the high temperature protection and bonding requirements of ceramic materials on high-speed aircraft and aircraft engines.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] The technical solution of the present invention provides a room temperature curing phosphate high temperature resistant material, which is composed of two component substances, wherein component one is a mixed inorganic phosphate chemical adhesive mixture, and component two is a solid mixture composed of a curing agent and a functional filler, and the mass ratio of component one to component two is 1:1.4-1.8.

[0007] In addition, the mixed inorganic phosphate chemical adhesive mixture is a mixture of modified aluminum dihydrogen phosphate, aluminum chromium phosphate, zirconium phosphate and deionized water; the mass fractions of aluminum dihydrogen phosphate, aluminum chromium phosphate, zirconium phosphate and deionized water are 60-80, 5-10, 5-10, and deionized water is 10-15 respectively.

[0008] Furthermore, the modification agent is a mixture of boron trioxide and boric acid, the mass fraction is 2 to 5 parts, and the modification process is a modification treatment at 80° C. for 2 h to 3 h.

[0009] In addition, the curing agent is a mixture of magnesium oxide, zinc oxide, calcium oxide and aluminum oxide; the mass fractions of magnesium oxide, zinc oxide, calcium oxide and aluminum oxide are 2-4, 3-8, 3-8 and 80-92 respectively.

[0010] In addition, the functional filler is one of silicon dioxide, quartz powder or silicon micropowder.

[0011] In addition, the mass ratio of the curing agent to the functional filler is 1:1.

[0012] The method for preparing the room temperature curing phosphate high temperature resistant material provided by the technical solution of the present invention is to grind and mix component one and component two evenly, and then pour them into blocks for bonding ceramic materials in a high temperature environment. In order to avoid the generation of bubbles during the pouring process, the vibration frequency during the pouring process is 20 to 50 Hz, and the vibration amplitude is not less than 0.4 mm.

[0013] Compared with the existing phosphate materials, the technical scheme of the present invention firstly improves the inorganic phosphate chemical adhesive, adopts a mixture of aluminum dihydrogen phosphate, aluminum chromium phosphate, zirconium phosphate and deionized water, and uses boron trioxide and boric acid to treat the phosphate mixture at 80°C for 2h to 3h for stability. The storage stability of the modified adhesive exceeds 12 months; secondly, the matching technology of the curing agent is optimized and the functional additives are added. The curing agent adopts a matching system of magnesium oxide, zinc oxide, calcium oxide and aluminum oxide. The high activity of magnesium oxide realizes room temperature curing and improves water resistance. The addition of zinc oxide and calcium oxide stabilizes the reaction speed and increases the operating space. The addition of aluminum oxide improves the high temperature resistance and strength of the system. The addition of functional additives improves the thermal stability of the material, so that the thermal expansion coefficient of the material (normal temperature to 1500°C) is lower than 3×10 -6 / ℃, combining the above technical methods, a room temperature curing phosphate high temperature resistant material was prepared, which can be cured at room temperature (room temperature operation time is not less than 30min, room temperature complete curing time is not more than 72h), can withstand 1500℃ high temperature (tensile shear strength at 1500℃ is greater than 2MPa), has excellent water resistance (tensile shear strength is greater than 2MPa after immersion in water for 7d), has high bonding strength (tensile shear strength at room temperature is 3MPa), and has high storage stability (storage period is 12 months). In summary, the characteristics and beneficial effects of the technical solution of the present invention can be summarized as follows:

[0014] 1. The present invention adopts a mixed phosphate chemical adhesive base material system, combined with a composite curing and filler system, taking into account the material's room temperature curing, high temperature resistance, water resistance, and other performance requirements;

[0015] Second, compared with the phosphate materials currently on the market, the phosphate materials prepared by the present invention have the advantages of room temperature curing, high temperature resistance, good water resistance and high bonding strength;

[0016] 3. The room temperature curing phosphate high temperature resistant material designed by the present invention has the advantages of simple preparation, simple molding process, few defects, etc. DETAILED DESCRIPTION

[0017] The technical solution of the present invention will be further described in detail below in conjunction with embodiments:

[0018] Embodiment 1:

[0019] The steps for preparing the room temperature curing phosphate high temperature resistant material of the present invention are as follows:

[0020] Step 1: using 75% concentration of orthophosphate to react with aluminum hydroxide and zirconium hydroxide at 90° C. to prepare aluminum dihydrogen phosphate and zirconium phosphate hydrate adhesives, adding chromium trioxide and 35% formaldehyde solution to the prepared aluminum dihydrogen phosphate hydrate adhesive, and heating to prepare chromium aluminum phosphate;

[0021] Step 2: Take 75 parts of prepared aluminum dihydrogen phosphate, 5 parts of aluminum chromium phosphate, 5 parts of zirconium phosphate, and 15 parts of deionized water, and stir and mix them evenly;

[0022] Step 3: Take 3 parts of magnesium oxide, 3 parts of zinc oxide, 8 parts of calcium oxide, 86 parts of aluminum oxide and 100 parts of quartz powder, grind and mix them evenly in a mortar;

[0023] Step 4: Take the hydrated adhesive mixed in step 2 and the mixed amount in step 3, grind and mix them evenly in a mortar in a ratio of 1:1.6;

[0024] Step 5. Using silicon carbide ceramic as the substrate, prepare the sample according to GJB444, and after room temperature vulcanization for 72 hours, test the tensile shear strength at -120°C, 23°C, 600°C, 1200°C and 1500°C. The test results are shown in Table 1.

[0025] Embodiment 2:

[0026] The steps for preparing the room temperature curing phosphate high temperature resistant material of the present invention are as follows:

[0027] Step 1: using 75% concentration of orthophosphate to react with aluminum hydroxide and zirconium hydroxide at 90° C. to prepare aluminum dihydrogen phosphate and zirconium phosphate hydrate adhesives, adding chromium trioxide and 35% formaldehyde solution to the prepared aluminum dihydrogen phosphate hydrate adhesive, and heating to prepare chromium aluminum phosphate;

[0028] Step 2: Take 70 parts of prepared aluminum dihydrogen phosphate, 5 parts of aluminum chromium phosphate, 5 parts of zirconium phosphate, and 20 parts of deionized water, and stir and mix them evenly;

[0029] Step 3: Take 2 parts of magnesium oxide, 5 parts of zinc oxide, 5 parts of calcium oxide, 92 parts of aluminum oxide and 100 parts of quartz powder, grind and mix them evenly in a mortar;

[0030] Step 4: Take the hydrated adhesive mixed in step 2 and the mixed amount in step 3, grind and mix them evenly in a mortar in a ratio of 1:1.8;

[0031] Step 5. On a vibration table, with a vibration frequency of 50 Hz and an amplitude of 0.4 mm, pour the glue mixed in step 4 into a 100mm*100mm*50mm soft silicone mold under the vibration quasi-state. After curing reaction for 24 hours, take it out of the mold, cure it for 48 hours, and then put it in a 1500℃ muffle furnace for 24 hours. Take it out and let it air at room temperature. The tested volume shrinkage rate is 0.5%.

[0032] Table 1 Tensile shear strength test results

[0033]

Claims

1. A room temperature curing phosphate high temperature resistant material, characterized in that: The material is composed of two components, wherein component one is a mixed inorganic phosphate chemical adhesive mixture, and component two is a solid mixture composed of a curing agent and a functional filler. The mass ratio of component one to component two is 1:1.4-1.

8.

2. The room temperature curing phosphate high temperature resistant material according to claim 1, characterized in that: The mixed inorganic phosphate chemical adhesive mixture is a mixture of modified aluminum dihydrogen phosphate, aluminum chromium phosphate, zirconium phosphate and deionized water; the mass fractions of aluminum dihydrogen phosphate, aluminum chromium phosphate, zirconium phosphate and deionized water are 60-80, 5-10, 5-10 and deionized water is 10-15 respectively.

3. The room temperature curing phosphate high temperature resistant material according to claim 2, characterized in that: The modification agent is a mixture of boron trioxide and boric acid, the mass fraction is 2 to 5 parts, and the modification process is a modification treatment at 80° C. for 2 hours to 3 hours.

4. The room temperature curing phosphate high temperature resistant material according to claim 1, characterized in that: The curing agent is a mixture of magnesium oxide, zinc oxide, calcium oxide and aluminum oxide; the mass fractions of magnesium oxide, zinc oxide, calcium oxide and aluminum oxide are 2-4, 3-8, 3-8 and 80-92 respectively.

5. The room temperature curing phosphate high temperature resistant material according to claim 1, characterized in that: The functional filler is one of silicon dioxide, quartz powder or silicon micropowder.

6. The room temperature curing phosphate high temperature resistant material according to claim 1, characterized in that: The mass ratio of the curing agent to the functional filler is 1:

1.

7. The method for preparing the room temperature curing phosphate high temperature resistant material according to claim 1, characterized in that: The method is to grind and mix component one and component two evenly, and then pour them into blocks for bonding ceramic materials in a high temperature environment. To avoid bubbles during the pouring process, the vibration frequency during the pouring process is 20 to 50 Hz, and the vibration amplitude is not less than 0.4 mm.

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