Preparation method of thermal protection coating on surface of basalt fiber composite material

Abstract

The invention relates to the technical field of protective coatings, and discloses a preparation method of a thermal protective coating on the surface of a basalt fiber composite material, and the preparation method comprises the following steps: preparing a thermal protective coating, spraying the thermal protective coating and curing the coating, the thermal protective coating is a polysilazane thermal protective coating, and the thermal protective coating is sprayed by adopting a gas spray gun. According to the preparation method of the thermal protection coating on the surface of the basalt fiber composite material, a relatively simple construction process is utilized, the thermal protection coating with excellent performance and controlled construction can be prepared, and the prepared polysilazane thermal protection coating and the resin-based basalt fiber composite material are attached to the surface of a matrix through molecular bonds and chemical bonds, so that the thermal protection coating can be applied to the surface of the resin-based basalt fiber composite material. The coating can meet the erosive wear at high temperature, meanwhile, under the working conditions of strong scouring and short-time aerodynamic scouring and ablation, the coating cannot be separated from a composite material matrix, and the coating has the performance of high temperature resistance and erosive wear resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of protective coatings, and in particular provides a method for preparing a thermal protective coating on the surface of a basalt fiber composite material. Background Art

[0002] The polyester resin, epoxy resin, polyimide resin, etc. commonly used in the matrix of resin-based basalt fiber composites currently have an operating temperature not exceeding 400°C. Their high temperature resistance and resistance to solid particle erosion and wear are insufficient, which leads to serious restrictions on the application of basalt fiber composites in high-tech fields, high-temperature wear and other complex working conditions.

[0003] Therefore, how to effectively improve the material's high temperature resistance, erosion and wear resistance, expand its scope of use and extend its service life has become an urgent problem to be solved. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a method for preparing a thermal protection coating on the surface of a basalt fiber composite material to solve the problems existing in the prior art.

[0005] The present invention provides a method for preparing a thermal protection coating on the surface of a basalt fiber composite material, comprising the following steps: Step 1: diluting the polysilazane resin with a diluent to obtain a polysilazane resin solution with a content of 20%, then mixing the diluted polysilazane resin solution, filler, and dispersant, and stirring, grinding, and diluting in sequence to obtain a polysilazane thermal protective coating, wherein the filler is a mixture of nano-silicon dioxide, zirconium oxide, and silicon carbide crystals in a mass ratio of 1:7-8:3-5, and the coating viscosity of the polysilazane thermal protective coating is 15-30s; Step 2: adding the polysilazane thermal protection coating into an air spray gun, and spraying the polysilazane thermal protection coating evenly onto the surface of the resin-based basalt fiber composite material, with the coating thickness controlled at 30 to 50 μm; Step 3: After the resin-based basalt fiber composite material sprayed with the thermal protection coating is left standing at room temperature, cured in an oven and naturally cooled, a polysilazane thermal protection coating is obtained.

[0006] Preferably, in step 1, the mass ratio of the diluted polysilazane resin solution, filler and dispersant is 40-50:20-30:1-5.

[0007] More preferably, in step 1, the polysilazane resin is methyl hydrogen silazane resin, epoxy modified silazane resin, polyester modified silazane resin, polyfluorosilazane resin, polyborosilazane resin or polyaluminosilazane resin.

[0008] More preferably, in step 1, the dispersant is graphite, carbon nanotube or graphene.

[0009] Further preferably, in step 1, the diluent is formed by mixing xylene and ethyl acetate in a mass ratio of 4:1.

[0010] Further preferably, in step 1, the stirring speed is 200-300 r / min, the grinding is carried out in a planetary ball mill, the grinding speed is controlled at 240-260 r / min, and the time is 2-3 h.

[0011] More preferably, in step 2, the pressure of the air spray gun is 0.4-0.6 MPa and the caliber is 0.8-1.5 mm.

[0012] Further preferably, in step 2, the resin-based basalt fiber composite material is a polyester-based basalt fiber composite material, an epoxy-based basalt fiber composite material, a polyimide-based basalt fiber composite material or a polyetheretherketone-based basalt fiber composite material.

[0013] It is further preferred that before the polysilazane thermal protection coating is uniformly sprayed onto the surface of the resin-based basalt fiber composite material, the step of surface treatment of the resin-based basalt fiber composite material is also included, wherein the surface treatment step is specifically as follows: the surface of the resin-based basalt fiber composite material is sandblasted with 24-46 mesh quartz sand or 80 mesh sandpaper, and then washed with anhydrous ethanol for 2-3 times, and then washed with a mixed solvent of xylene and ethyl acetate with a mass ratio of 4:1 for 3-4 times, and left to dry to constant weight.

[0014] Further preferably, in step 3, the resin-based basalt fiber composite material sprayed with the thermal protective coating is placed in a room temperature environment for 10 to 20 hours, then transferred to an oven, heated to 70 to 80°C at a heating rate of 5 to 10°C / min, and then cured at a constant temperature for 30 to 40 minutes, and then continued to heat to 100 to 120°C at a heating rate of 5 to 10°C / min, and cured at a constant temperature for 1 to 2 hours. After that, it is naturally cooled to below 80°C to obtain a polysilazane thermal protective coating.

[0015] The method for preparing the thermal protection coating on the surface of the basalt fiber composite material provided by the present invention has the following beneficial effects: 1. The present invention can successfully attach the polysilazane thermal protection coating to the surface of the resin-based basalt fiber composite material by using an air spraying method to form a thermal protection coating, which can improve the high temperature resistance and solid particle erosion and wear resistance of the resin-based basalt fiber composite material; 2. The present invention utilizes the prepared polysilazane thermal protective coating to prepare a thermal protective coating with excellent performance and controlled construction through a relatively simple construction process, while reducing the damage of high temperature to the composite material matrix during the construction of the thermal protective coating prepared by thermal spraying or cold spraying; 3. The polysilazane thermal protection coating prepared by the present invention is attached to the surface of the resin-based basalt fiber composite material matrix by molecular bonds and chemical bonds, which can meet the erosion and wear under high temperature. At the same time, the coating will not separate from the composite material matrix under strong erosion and short-term aerodynamic erosion and ablation conditions. DETAILED DESCRIPTION

[0016] The present invention will be further explained below in conjunction with specific implementation schemes, but the present invention is not limited thereto.

[0017] Example 1

[0018] The preparation method of the thermal protection coating on the surface of the epoxy basalt fiber composite material comprises the following steps: Step 1: Prepare thermal protective coating: dilute the methylhydrogensilazane resin with a diluent to obtain a methylhydrogensilazane resin solution with a content of 20%, then stir 40g of the diluted methylhydrogensilazane resin solution, 25g of filler (nano-silicon dioxide, zirconium oxide, silicon carbide crystals mixed in a mass ratio of 1:7:3) and 1g of dispersant graphite at a stirring speed of 200r / min, and then transfer to a planetary ball mill for grinding, the speed is controlled at 260r / min, the time is 2h, and after the grinding is completed, a diluent is added for dilution, and the viscosity is controlled at 15s, and finally a polysilazane thermal protective coating is obtained, wherein the diluent is mixed with xylene and ethyl acetate in a mass ratio of 4:1; Step 2: Thermal protection coating spraying process: add the obtained polysilazane thermal protection coating to an air spray gun, and spray the coating evenly onto the surface of the epoxy-based basalt fiber composite material under the conditions of a pressure of 0.4 MPa and a spray gun diameter of 1 mm. The coating thickness is controlled at 40 μm. Before spraying, the epoxy-based basalt fiber composite material substrate is surface treated: the composite material surface is sandblasted with 46-mesh quartz sand, then washed 3 times with anhydrous ethanol, and then washed 4 times with a mixed solvent of xylene and ethyl acetate with a mass ratio of 4:1, and dried to constant weight to obtain a resin-based basalt fiber composite material substrate after surface treatment; Step 3: Coating curing: Place the composite material sprayed with the thermal protective coating in a room temperature environment for 12 hours, then transfer it to an oven, heat it to 80°C at a heating rate of 5°C / min, and cure it at a constant temperature for 30 minutes. Then, continue to heat it to 120°C at a heating rate of 5°C / min, cure it at a constant temperature for 2 hours, and naturally cool it to below 80°C to obtain a polysilazane thermal protective coating.

[0019] The thermal protective coating was tested using a high-temperature explosion particle airflow scouring test. After experiencing scouring and wear by a high-temperature explosion particle airflow of more than 1000°C for 5 times, the thermal protective coating showed no obvious changes.

[0020] Example 2

[0021] The preparation method of the thermal protection coating on the surface of the polyimide-based basalt fiber composite material comprises the following steps: Step 1: Prepare thermal protective coating: dilute the polyborosilazane resin with a diluent to obtain a polyborosilazane resin solution with a content of 20%, then stir 40g of the diluted polyborosilazane resin solution, 30g of filler (nano-silica, zirconium oxide, silicon carbide crystals mixed in a mass ratio of 1:8:5) and 5g of dispersant carbon nanotubes at a stirring speed of 300r / min, and then transfer to a planetary ball mill for grinding, the speed is controlled at 240r / min, the time is 3h, after the grinding is completed, add a diluent for dilution, and control the viscosity of the coating to 30s, and finally obtain a polysilazane thermal protective coating, wherein the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 4:1; Step 2: Thermal protection coating spraying process: add the obtained polysilazane thermal protection coating to an air spray gun, and spray the coating evenly onto the surface of the polyimide-based basalt fiber composite material under the conditions of a pressure of 0.6 MPa and a spray gun caliber of 1.5 mm. The coating thickness is controlled at 40 μm. Before spraying, the polyimide-based basalt fiber composite material substrate is surface treated: the composite material surface is sandblasted with 24-mesh quartz sand, then washed twice with anhydrous ethanol, and then washed three times with a mixed solvent of xylene and ethyl acetate in a mass ratio of 4:1, and then dried to constant weight to obtain a surface-treated resin-based basalt fiber composite material substrate; Step 3: Coating curing: Place the composite material sprayed with the thermal protective coating in a room temperature environment for 10 hours, then transfer it to an oven, heat it to 70°C at a heating rate of 5°C / min, and cure it at a constant temperature for 40 minutes. Then, continue to heat it to 100°C at a heating rate of 5°C / min, cure it at a constant temperature for 1 hour, and naturally cool it to below 80°C to obtain a polysilazane thermal protective coating.

[0022] The thermal protective coating was tested using a high-temperature explosion particle airflow scouring test. After experiencing scouring and wear by a high-temperature explosion particle airflow of more than 1000°C for 6 times, the thermal protective coating showed no obvious changes.

[0023] Example 3

[0024] The preparation method of the thermal protection coating on the surface of the polyimide-based basalt fiber composite material comprises the following steps: Step 1: Prepare thermal protective coating: dilute the polyaluminum silazane resin with a diluent to obtain a polyaluminum silazane resin solution with a content of 20%, then stir 50g of the diluted polyaluminum silazane resin solution, 20g of filler (nano-silicon dioxide, zirconium oxide, silicon carbide crystals mixed in a mass ratio of 1:7:5) and 1g of dispersant graphite at a stirring speed of 250r / min, and then transfer to a planetary ball mill for grinding, the speed is controlled at 250r / min, the time is 2.5h, after the grinding is completed, add a diluent for dilution, and control the viscosity of the coating to 25s, and finally obtain a polysilazane thermal protective coating, wherein the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 4:1; Step 2: Thermal protection coating spraying process: add the obtained polysilazane thermal protection coating to an air spray gun, and spray the coating evenly onto the surface of the polyimide-based basalt fiber composite material under the conditions of a pressure of 0.5 MPa and a spray gun caliber of 1 mm. The coating thickness is controlled at 30 μm. Before spraying, the polyimide-based basalt fiber composite material substrate is surface treated: the composite material surface is polished with 80-mesh sandpaper, then washed with anhydrous ethanol for 3 times, and then washed with a mixed solvent of xylene and ethyl acetate with a mass ratio of 4:1 for 4 times, and then dried to constant weight to obtain a resin-based basalt fiber composite material substrate after surface treatment; Step 3: Coating curing: Place the composite material sprayed with the thermal protective coating in a room temperature environment for 20 hours, then transfer it to an oven, heat it to 80°C at a heating rate of 5°C / min, and cure it at a constant temperature for 30 minutes. Then, continue to heat it to 100°C at a heating rate of 5°C / min, cure it at a constant temperature for 2 hours, and naturally cool it to below 80°C to obtain a polysilazane thermal protective coating.

[0025] The thermal protective coating was tested using a high-temperature explosion particle airflow scouring test. After experiencing scouring and wear by a high-temperature explosion particle airflow of more than 1000°C for 6 times, the thermal protective coating showed no obvious changes.

[0026] Example 4

[0027] The preparation method of the thermal protection coating on the surface of polyetheretherketone-based basalt fiber composite material comprises the following steps: Step 1: Prepare thermal protective coating: dilute the polyfluorosilazane resin with a diluent to obtain a polyfluorosilazane resin solution with a content of 20%, then stir 45g of the diluted polyfluorosilazane resin solution, 25g of filler (nano-silicon dioxide, zirconium oxide, silicon carbide crystals mixed in a mass ratio of 1:8:3) and 3g of dispersant graphene at a stirring speed of 280r / min, and then transfer to a planetary ball mill for grinding, the speed is controlled at 260r / min, the time is 2h, and after the grinding is completed, a diluent is added for dilution, and the viscosity is controlled at 25s, and finally a polysilazane thermal protective coating is obtained, wherein the diluent is mixed with xylene and ethyl acetate in a mass ratio of 4:1; Step 2: Thermal protection coating spraying process: add the obtained polysilazane thermal protection coating to an air spray gun, and spray the coating evenly onto the surface of the polyetheretherketone-based basalt fiber composite material under the conditions of a pressure of 0.4MPa and a spray gun diameter of 0.8mm. The coating thickness is controlled at 50μm. Before spraying, the polyetheretherketone-based basalt fiber composite material substrate is surface treated: the composite material surface is sandblasted with 38-mesh quartz sand, then washed twice with anhydrous ethanol, and then washed four times with a mixed solvent of xylene and ethyl acetate with a mass ratio of 4:1, and dried to constant weight to obtain a surface-treated resin-based basalt fiber composite material substrate; Step 3: Coating curing: Place the composite material sprayed with the thermal protective coating in a room temperature environment for 15 hours, then transfer it to an oven, heat it to 80°C at a heating rate of 10°C / min, and cure it at a constant temperature for 35 minutes. Then, continue to heat it to 110°C at a heating rate of 10°C / min, cure it at a constant temperature for 2 hours, and naturally cool it to below 70°C to obtain a polysilazane thermal protective coating.

[0028] The thermal protective coating was tested using a high-temperature explosion particle airflow scouring test. After experiencing scouring and wear by a high-temperature explosion particle airflow of more than 1000°C for 6 times, the thermal protective coating showed no obvious changes.

[0029] Example 5

[0030] The preparation method of the thermal protection coating on the surface of the polyester-based basalt fiber composite material comprises the following steps: Step 1: Prepare thermal protective coating: dilute the polyester modified silazane resin with a diluent to obtain a polyester modified silazane resin solution with a content of 20%, then stir 45g of the diluted polyester modified silazane resin solution, 30g of filler (nano-silicon dioxide, zirconium oxide, silicon carbide crystals mixed in a mass ratio of 1:7:4) and 2g of dispersant graphite at a stirring speed of 300r / min, and then transfer to a planetary ball mill for grinding, the speed is controlled at 260r / min, the time is 3h, after the grinding is completed, add a diluent for dilution, and control the viscosity of the coating to 20s, and finally obtain a polysilazane thermal protective coating, wherein the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 4:1; Step 2: Thermal protection coating spraying process: add the obtained polysilazane thermal protection coating to an air spray gun, and spray the coating evenly onto the surface of the polyester-based basalt fiber composite material under the conditions of a pressure of 0.4 MPa and a spray gun caliber of 0.8 mm. The coating thickness is controlled at 30 μm. Before spraying, the polyester-based basalt fiber composite material substrate is surface treated: the composite material surface is sandblasted with 30 mesh quartz sand, then washed 3 times with anhydrous ethanol, and then washed 4 times with a mixed solvent of xylene and ethyl acetate with a mass ratio of 4:1, and then dried to constant weight to obtain a resin-based basalt fiber composite material substrate after surface treatment; Step 3: Coating curing: Place the composite material sprayed with the thermal protective coating in a room temperature environment for 18 hours, then transfer it to an oven, heat it to 80°C at a heating rate of 5°C / min, and cure it at a constant temperature for 30 minutes. Then, continue to heat it to 120°C at a heating rate of 5°C / min, cure it at a constant temperature for 2 hours, and naturally cool it to below 80°C to obtain a polysilazane thermal protective coating.

[0031] The thermal protective coating was tested using a high-temperature explosion particle airflow scouring test. After experiencing scouring and wear by a high-temperature explosion particle airflow of more than 1000°C for 6 times, the thermal protective coating showed no obvious changes.

[0032] The method for preparing the thermal protective coating on the surface of the basalt fiber composite material provided by the present invention can prepare a thermal protective coating with excellent performance and controlled construction by using a relatively simple construction process. The prepared polysilazane thermal protective coating and the resin-based basalt fiber composite material are attached to the surface of the substrate by molecular bonds and chemical bonds, and can meet the erosion and wear under high temperature. At the same time, under strong scouring and short-term aerodynamic scouring and ablation conditions, the coating will not separate from the composite material substrate, and has the performance of high temperature resistance and erosion and wear resistance.

[0033] The embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A method for preparing a thermal protective coating on the surface of a basalt fiber composite material, characterized in that: The steps include: Step 1: diluting the polysilazane resin with a diluent to obtain a polysilazane resin solution with a content of 20%, then mixing the diluted polysilazane resin solution, filler, and dispersant, and stirring, grinding, and diluting in sequence to obtain a polysilazane thermal protective coating, wherein the filler is a mixture of nano-silicon dioxide, zirconium oxide, and silicon carbide crystals in a mass ratio of 1:7-8:3-5, and the coating viscosity of the polysilazane thermal protective coating is 15-30s; Step 2: adding the polysilazane thermal protection coating into an air spray gun, and spraying the polysilazane thermal protection coating evenly onto the surface of the resin-based basalt fiber composite material, with the coating thickness controlled at 30 to 50 μm; Step 3: After the resin-based basalt fiber composite material sprayed with the thermal protection coating is left standing at room temperature, cured in an oven and naturally cooled, a polysilazane thermal protection coating is obtained.

2. The method for preparing the thermal protection coating on the surface of the basalt fiber composite material according to claim 1, characterized in that: In step 1, the mass ratio of the diluted polysilazane resin solution, filler and dispersant is 40-50:20-30:1-5.

3. The method for preparing the thermal protection coating on the surface of the basalt fiber composite material according to claim 1, characterized in that: In step 1, the polysilazane resin is methyl hydrogen silazane resin, epoxy modified silazane resin, polyester modified silazane resin, polyfluorosilazane resin, polyborosilazane resin or polyaluminosilazane resin.

4. The method for preparing the thermal protection coating on the surface of the basalt fiber composite material according to claim 1, characterized in that: In step 1, the dispersant is graphite, carbon nanotube or graphene.

5. The method for preparing the thermal protection coating on the surface of the basalt fiber composite material according to claim 1, characterized in that: In step 1, the diluent is prepared by mixing xylene and ethyl acetate in a mass ratio of 4:

1.

6. The method for preparing the thermal protection coating on the surface of the basalt fiber composite material according to claim 1, characterized in that: In step 1, the stirring speed is 200-300 r / min, the grinding is carried out in a planetary ball mill, the grinding speed is controlled at 240-260 r / min, and the time is 2-3 h.

7. The method for preparing the thermal protection coating on the surface of basalt fiber composite material according to claim 1, characterized in that: In step 2, the pressure of the air spray gun is 0.4-0.6 MPa and the caliber is 0.8-1.5 mm.

8. The method for preparing the thermal protection coating on the surface of basalt fiber composite material according to claim 1, characterized in that: In step 2, the resin-based basalt fiber composite material is a polyester-based basalt fiber composite material, an epoxy-based basalt fiber composite material, a polyimide-based basalt fiber composite material or a polyetheretherketone-based basalt fiber composite material.

9. The method for preparing the thermal protection coating on the surface of basalt fiber composite material according to claim 1, characterized in that: Before the polysilazane thermal protection coating is uniformly sprayed onto the surface of the resin-based basalt fiber composite material, the method also includes a step of surface treating the resin-based basalt fiber composite material, wherein the surface treatment step is specifically as follows: the surface of the resin-based basalt fiber composite material is sandblasted with 24-46 mesh quartz sand or 80 mesh sandpaper, and then washed with anhydrous ethanol for 2-3 times, and then washed with a mixed solvent of xylene and ethyl acetate with a mass ratio of 4:1 for 3-4 times, and left to dry until constant weight.

10. The method for preparing the thermal protection coating on the surface of basalt fiber composite material according to claim 1, characterized in that: In step 3, the resin-based basalt fiber composite material sprayed with the thermal protective coating is placed in a room temperature environment for 10 to 20 hours, then transferred to an oven, heated to 70 to 80°C at a heating rate of 5 to 10°C / min, and then cured at a constant temperature for 30 to 40 minutes. Then, the temperature is continued to be heated to 100 to 120°C at a heating rate of 5 to 10°C / min, and cured at a constant temperature for 1 to 2 hours. After that, it is naturally cooled to below 80°C to obtain a polysilazane thermal protective coating.