A method for rapid repair of damage defects of SiC ceramic matrix composite material

Abstract

The application provides a SiC ceramic matrix composite damage defect rapid repairing method and relates to the field of composite material repairing. First, a carbon film is prepared on the surface of the SiC ceramic matrix composite through a slurry brushing method; second, SiC ceramic powder is compounded in the defect area of the SiC ceramic matrix composite through a slurry impregnation method, the ceramic powder is sintered into a SiC skeleton by using a local infrared heating method, and SiC nanowires and PyC interfaces are prepared in the defect area by using a chemical vapor deposition method; finally, a ceramic matrix is compounded in the defect area of the SiC ceramic matrix composite in situ by using a precursor impregnation and pyrolysis method, and thus the rapid repairing of the defect area of the SiC ceramic matrix composite is completed. The application repairs the defect of the SiC ceramic matrix composite by using the local infrared heating method, reduces the secondary damage of the base material, has high repairing efficiency, has high compactness of the defect area after repairing, has excellent mechanical properties, and can be applied to the repairing of damage defects such as cracks, delamination and block shedding.

Description

Technical Field

[0001] This invention relates to the field of composite material repair, and more particularly to a rapid repair method for damage and defects in SiC ceramic matrix composite materials. Technical Background

[0002] SiC ceramic matrix composites possess superior performance and are advanced materials for achieving weight reduction and efficiency improvement in aero-engines. SiC ceramic matrix composites are a type of composite material made by combining SiC ceramics with C or SiC fibers. They exhibit metallic fracture toughness, are insensitive to cracks, and do not suffer catastrophic damage. While maintaining the excellent properties of traditional ceramic materials such as high temperature resistance, high strength, high stiffness, low density, and corrosion resistance, they overcome the fatal weakness of high brittleness, improving their toughness and reliability. Compared with nickel-based superalloys, SiC ceramic matrix composites have outstanding advantages such as high temperature resistance, low density, and excellent high-temperature oxidation resistance, and are considered a strategic thermal structural material for next-generation aero-engines, and one of the core technologies of future engines. SiC ceramic matrix composites are mainly used to manufacture components such as turbine blades and combustion chambers of engines. These thermal structural components undergo repeated thermal shocks at low, medium, and high temperatures and are exposed to exhaust atmospheres across the entire temperature range, resulting in harsh service environments. Material oxidation and ablation are severe, and cracks, delamination, and spalling damage account for more than 50% of all damage and failure in composite materials. The preparation cycle of SiC ceramic matrix composites is long and the cost is high. Localized infrared heating is a simple, low-temperature, fast-sintering, short-holding-time, and low-cost ceramic preparation method that can prepare ceramic matrix composites in a short time. It has become a major method for ceramic repair. Patent CN202110752716.7 relates to a repair agent and method for surface damage of silicon carbide ceramic matrix composites. It uses a reasonable ratio of solid polycarbosilane, xylene, zirconium carbide powder, silicon carbide powder, and silicon carbide whiskers to form a repair agent with suitable viscosity, which is then used to repair the ceramic matrix composite through precursor impregnation pyrolysis. Patent CN201410389924.5 relates to a repair method for continuous fiber-reinforced ceramic matrix composites. It uses a prepreg decomposed material coated with boron carbide and silicon nitride nanoparticle slurry, which penetrates the large gaps between fiber bundles. SiC is then prepared using chemical vapor impregnation, densifying the gaps in the composite material. Patent CN202310111944.5 relates to a repair method for localized damage and microcracks in small and medium-sized SiC / SiC composite materials. Solid and liquid polycarbosilanes are mixed to form a precursor slurry. Samples are placed in the slurry and ultrasonically impregnated. The ceramic matrix composite is then repaired through curing-high-temperature pyrolysis. The previous patents involved overall heating of the SiC ceramic matrix composite, causing secondary damage to the parent material and leading to a decrease in composite material performance. This patent utilizes localized infrared heating technology to reduce this secondary damage. This preparation method is highly efficient and low-cost, showing great potential for future SiC ceramic matrix composite repair. Summary of the Invention

[0003] The purpose of this invention is to propose a rapid repair method for damage and defects in SiC ceramic matrix composites. The method uses local infrared heating technology to repair damage and defects in SiC ceramic matrix composites. After repair, the composite material has high density, a tight bond between the parent material and the repaired material, minimal secondary damage to the parent material, and high repair efficiency.

[0004] To achieve the above objectives, the present invention provides a rapid repair method for damage defects in SiC ceramic matrix composite materials, characterized in that the method includes the following steps:

[0005] Step (1): Dissolve phenolic resin with a mass fraction of 40-60 wt.% in an ethanol solution to prepare a phenolic resin slurry. Apply the phenolic resin slurry to the surface of the SiC ceramic matrix composite material using a slurry brushing method. Place the coated SiC ceramic matrix composite material in a vacuum drying oven for curing at a temperature of 120-180℃ for 3-6 hours. Place the cured SiC ceramic matrix composite material in a tube furnace for pyrolysis at a temperature of 600-800℃ for 30-60 minutes to prepare a carbon film on the surface of the SiC ceramic matrix composite material.

[0006] Step (2): Prepare a mixed powder. The mass fraction of each component in the mixed powder is: 85-90 wt.% of SiC powder with a particle size of 0.5-5 μm, 5-10 wt.% of MoSi2 powder with a particle size of 5-10 μm, 2-3 wt.% of SiC nanowire catalyst, and 2-3 wt.% of ceramic powder dispersant. Dissolve 40-60 wt.% of the mixed powder in deionized water and ball mill it in a planetary ball mill at a speed of 140-200 r / min for 16-24 h to prepare a ceramic suspension slurry. The SiC ceramic matrix composite material is impregnated in a ceramic suspension slurry under vacuum for 30-60 minutes, followed by pressure impregnation at 1-3 MPa for 3-6 hours. After impregnation, the SiC ceramic matrix composite material is placed in a vacuum drying oven for vacuum drying at 80-120℃ for 2-3 hours. The SiC ceramic matrix composite material is then placed in a local infrared heating furnace to sinter the mixed powder in the defect area, with argon gas protection introduced. The heating temperature is 1800-2100℃ for 2-3 minutes, thus obtaining a SiC framework in the defects of the SiC ceramic matrix composite material.

[0007] Step (3): Trichloromethylsilane, hydrogen and argon are introduced into a local infrared heating furnace. The flow rate of trichloromethylsilane is 10-15 ml / min, the flow rates of hydrogen and argon are 100-150 ml / min, the local infrared heating rate is 800-1000℃ / min, the heating temperature is 1100-1500℃, and the time is 5-10 min. A three-dimensional spatial network of SiC nanowires is prepared in the defects of SiC ceramic matrix composite material.

[0008] Step (4): Close the hydrogen and trichloromethylsilane gas path of the local infrared heating furnace, continue to introduce argon gas, use argon gas to remove residual hydrogen and trichloromethylsilane, then introduce propylene, use propylene as carbon source to prepare PyC interface on SiC framework and three-dimensional SiC nanowire surface, propylene gas flow rate is 40-80 ml / min, argon gas flow rate is 100-200 ml / min, heat treatment temperature is 800-1000℃, heat treatment time is 10-15 min;

[0009] Step (5): 20-40 wt.% of SiC powder with a particle size of 50-150 nm is dispersed in a polymer precursor solution. The SiC ceramic matrix composite material is placed in a polymer precursor solution impregnation tank containing a vibration table and impregnated under vacuum for 1-2 hours, followed by pressure impregnation under 1-3 MPa for 2-3 hours. The vibration frequency of the vibration table is 100-500 Hz, and the maximum amplitude is 5-10 mm. The impregnated composite material is then cured in a vacuum oven at a curing temperature of 120-220℃ for 3-5 hours. The cured composite material is then pyrolyzed in a local infrared heating furnace at a pyrolysis temperature of 1100-1300℃ for 2-4 hours to finally repair defects in the SiC ceramic matrix composite material. Further, the SiC ceramic matrix composite material mentioned in step (1) is either a C / SiC composite material or a SiC / SiC composite material.

[0010] Furthermore, the SiC nanowire catalyst mentioned in step (2) is one of metallic iron, metallic nickel, ferric nitrate, nickel nitrate, and ferrocene.

[0011] Furthermore, the dispersant mentioned in step (2) is one of resin arabic, sodium tripolyphosphate, sodium polyacrylate, sodium hexametaphosphate, and sodium citrate.

[0012] Furthermore, the defects in the SiC ceramic matrix composite material mentioned in step (2) are one of the following: cracks, delamination, and spalling of the SiC ceramic matrix composite material.

[0013] Furthermore, the polymer precursor solution in step (5) is one of polysilane, polycarbosilane, polysilazane, and polysiloxane.

[0014] Beneficial effects

[0015] (1) The SiC skeleton prepared by placing SiC ceramic matrix composite material in a local infrared heating furnace can not only fill the defect area and improve the density of the repair area of ​​the composite material, but also improve the performance of the composite material. The damaged size of the ceramic matrix composite material is large and the capillary force is small, which is not conducive to the impregnation of polymer precursor solution. The SiC skeleton prepared by local infrared heating method reduces the size of the damaged area and increases the capillary force, which is conducive to the subsequent impregnation-curing-pyrolysis of polymer precursor solution to generate ceramic matrix.

[0016] (2) The present invention uses a local infrared heating furnace to prepare the PyC interface. The PyC interface can avoid the damage of the polymer precursor to the SiC nanowires during the subsequent composite matrix. The PyC interface is deposited on the surface of the SiC nanowires and the SiC skeleton, which promotes crack deflection, consumes fracture energy, and improves the performance of the repaired SiC ceramic matrix composite material.

[0017] (3) The present invention uses a local infrared heating method to prepare SiC framework, SiC nanowire reinforcement phase, PyC interface and ceramic matrix. The local infrared heating method has high preparation efficiency, reduces secondary damage to the parent material, and has high density and excellent mechanical properties in the repaired area.

[0018] This patent can reduce secondary damage to the parent material through local infrared heating technology. The preparation method is highly efficient and low-cost, and has great potential for future repair of SiC ceramic matrix composite materials. Detailed Implementation

[0019] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0020] Example 1

[0021] A rapid repair method for damage defects in SiC ceramic matrix composite materials, characterized by comprising the following steps:

[0022] Step (1): Dissolve 40 wt.% phenolic resin in ethanol solution, and apply the phenolic resin slurry to the surface of SiC / SiC ceramic matrix composite material by slurry brushing method. Place the coated SiC / SiC ceramic matrix composite material in a vacuum drying oven for curing at 120℃ for 6 hours. Place the cured SiC / SiC ceramic matrix composite material in a tube furnace for pyrolysis at 800℃ for 30 minutes to prepare a carbon film on the surface of SiC / SiC ceramic matrix composite material.

[0023] Step (2): Prepare a mixed powder. The mass fraction of each component in the mixed powder is: 90 wt.% of 5 μm SiC powder, 5 wt.% of 10 μm MoSi2 powder, 3 wt.% of ferric nitrate, and 2 wt.% of sodium tripolyphosphate. Dissolve 40 wt.% of the mixed powder in deionized water and ball mill it at 200 r / min for 16 h in a planetary ball mill. Impregnate the SiC / SiC composite material in a ceramic suspension slurry, vacuum impregnate for 60 min, and pressurize under 3 MPa pressure for 3 h. After impregnation, place the SiC / SiC composite material in a vacuum drying oven and vacuum dry it at 80℃ for 2 h. Place the SiC / SiC composite material in a local infrared heating furnace to sinter the mixed powder in the cracked area, purging with argon gas for protection, heating at 2100℃ for 2 min, and obtain the SiC skeleton in the defects of the SiC / SiC composite material.

[0024] Step (3): Trichloromethylsilane, hydrogen and argon are introduced into a local infrared heating furnace. The flow rate of trichloromethylsilane is 10 ml / min, the flow rate of hydrogen and argon is 100 ml / min, the local infrared heating rate is 800℃ / min, the heating temperature is 1100℃, and the time is 10 min. A three-dimensional spatial network of SiC nanowires is prepared in the defects of SiC / SiC composite material.

[0025] Step (4): Close the hydrogen and trichloromethylsilane gas path of the local infrared heating furnace, continue to introduce argon gas, use argon gas to remove residual hydrogen and trichloromethylsilane, then introduce propylene, use propylene as carbon source to prepare PyC interface on SiC framework and three-dimensional SiC nanowire surface, propylene gas flow rate is 80 ml / min, argon gas flow rate is 200 ml / min, heat treatment temperature is 1000℃, heat treatment time is 10 min;

[0026] Step (5): 20 wt.% of 50 nm SiC powder is dispersed in polycarbosilane. The SiC / SiC composite material is placed in a polycarbosilane impregnation tank containing a vibration table and impregnated under vacuum for 1 h, then under pressure of 1 MPa for 3 h. The vibration frequency of the vibration table is 100 Hz and the maximum amplitude is 10 mm. The impregnated composite material is then placed in a vacuum oven for curing at 220 °C for 3 h. The cured composite material is then placed in a local infrared heating furnace for pyrolysis at 1300 °C for 2 h, which finally repairs the crack defects in the SiC / SiC composite material.

[0027] Example 2

[0028] A rapid repair method for damage defects in SiC ceramic matrix composite materials, characterized by comprising the following steps:

[0029] Step (1): Dissolve 60 wt.% phenolic resin in ethanol solution, and apply the phenolic resin slurry to the surface of C / SiC ceramic matrix composite material by slurry brushing method. Place the coated C / SiC ceramic matrix composite material in a vacuum drying oven for curing at 180℃ for 3 hours. Place the cured C / SiC ceramic matrix composite material in a tube furnace for pyrolysis at 600℃ for 60 minutes to prepare a carbon film on the surface of C / SiC ceramic matrix composite material.

[0030] Step (2): Prepare a mixed powder. The mass fraction of each component in the mixed powder is: 85 wt.% of 0.5 μm SiC powder, 10 wt.% of 5 μm MoSi2 powder, 2 wt.% of metallic nickel, and 3 wt.% of sodium polyacrylate. Dissolve 60 wt.% of the mixed powder in deionized water and ball mill it in a planetary ball mill at 140 r / min for 24 h. Impregnate the C / SiC composite material in a ceramic suspension slurry, vacuum impregnate for 30 min, and pressurize under 1 MPa pressure for 6 h. After impregnation, place the C / SiC composite material in a vacuum drying oven and vacuum dry it at 120℃ for 3 h. Place the C / SiC composite material in a local infrared heating furnace to sinter the mixed powder in the layered region, purging with argon gas for protection, heating at 1800℃ for 3 min, and obtain the SiC skeleton in the defects of the C / SiC composite material.

[0031] Step (3): Trichloromethylsilane, hydrogen and argon are introduced into a local infrared heating furnace. The flow rate of trichloromethylsilane is 15 ml / min, the flow rate of hydrogen and argon is 150 ml / min, the local infrared heating rate is 1000℃ / min, the heating temperature is 1500℃, and the time is 5 min. A three-dimensional spatial network of SiC nanowires is prepared in the defects of C / SiC composite material.

[0032] Step (4): Turn off the hydrogen and trichloromethylsilane gas path of the local infrared heating furnace, continue to introduce argon gas, use argon gas to remove the residual hydrogen and trichloromethylsilane, and then introduce propylene. Using propylene as a carbon source, prepare PyC interface on the SiC framework and the surface of three-dimensional SiC nanowires. The propylene gas flow rate is 40 ml / min, the argon gas flow rate is 100 ml / min, the heat treatment temperature is 800℃, and the heat treatment time is 15 min.

[0033] Step (5): 40 wt.% of SiC powder with a particle size of 150 nm is dispersed in polysilazane. The C / SiC composite material is placed in a polymer precursor solution impregnation tank containing a vibration table and impregnated under vacuum for 2 h, and then under pressure of 3 MPa for 2 h. The vibration frequency of the vibration table is 500 Hz and the maximum amplitude is 5 mm. The impregnated C / SiC composite material is placed in a vacuum oven for curing at a curing temperature of 120 °C for 5 h. The cured C / SiC composite material is then placed in a local infrared heating furnace for pyrolysis at a pyrolysis temperature of 1100 °C for 4 h, which finally repairs the delamination defects of the C / SiC composite material.

Claims

1. A rapid repair method for damage defects in SiC ceramic matrix composite materials, characterized in that, The method includes the following steps: Step (1): Dissolve phenolic resin with a mass fraction of 40-60 wt.% in an ethanol solution to prepare a phenolic resin slurry. Apply the phenolic resin slurry to the surface of the SiC ceramic matrix composite material using a slurry brushing method. Place the coated SiC ceramic matrix composite material in a vacuum drying oven for curing at a temperature of 120-180℃ for 3-6 hours. Place the cured SiC ceramic matrix composite material in a tube furnace for pyrolysis at a temperature of 600-800℃ for 30-60 minutes to prepare a carbon film on the surface of the SiC ceramic matrix composite material. Step (2): Prepare a mixed powder. The mass fraction of each component in the mixed powder is: 85-90 wt.% of SiC powder with a particle size of 0.5-5 μm, 5-10 wt.% of MoSi2 powder with a particle size of 5-10 μm, 2-3 wt.% of SiC nanowire catalyst, and 2-3 wt.% of ceramic powder dispersant. Dissolve 40-60 wt.% of the mixed powder in deionized water and ball mill it in a planetary ball mill at a speed of 140-200 r / min for 16-24 h to prepare a ceramic suspension slurry. The SiC ceramic matrix composite material is impregnated in a ceramic suspension slurry under vacuum for 30-60 minutes, followed by pressure impregnation at 1-3 MPa for 3-6 hours. After impregnation, the SiC ceramic matrix composite material is placed in a vacuum drying oven for vacuum drying at 80-120℃ for 2-3 hours. The SiC ceramic matrix composite material is then placed in a local infrared heating furnace to sinter the mixed powder in the defect area, with argon gas protection introduced. The heating temperature is 1800-2100℃ for 2-3 minutes, thus obtaining a SiC framework in the defects of the SiC ceramic matrix composite material. Step (3): Trichloromethylsilane, hydrogen and argon are introduced into a local infrared heating furnace. The flow rate of trichloromethylsilane is 10-15 ml / min, the flow rates of hydrogen and argon are 100-150 ml / min, the local infrared heating rate is 800-1000℃ / min, the heating temperature is 1100-1500℃, and the time is 5-10 min. A three-dimensional spatial network of SiC nanowires is prepared in the defects of SiC ceramic matrix composite material. Step (4): Close the hydrogen and trichloromethylsilane gas path of the local infrared heating furnace, continue to introduce argon gas, use argon gas to remove residual hydrogen and trichloromethylsilane, then introduce propylene, use propylene as carbon source to prepare PyC interface on SiC framework and three-dimensional SiC nanowire surface, propylene gas flow rate is 40-80 ml / min, argon gas flow rate is 100-200 ml / min, heat treatment temperature is 800-1000℃, heat treatment time is 10-15 min; Step (5): 20-40 wt.% of SiC powder with a particle size of 50-150 nm is dispersed in a polymer precursor solution. The SiC ceramic matrix composite material is placed in a polymer precursor solution impregnation tank containing a vibration table and impregnated under vacuum for 1-2 h, and then under pressure of 1-3 MPa for 2-3 h. The vibration frequency of the vibration table is 100-500 Hz and the maximum amplitude is 5-10 mm. The impregnated composite material is then placed in a vacuum oven for curing at a temperature of 120-220 °C for 3-5 h. The cured composite material is then placed in a local infrared heating furnace for pyrolysis at a temperature of 1100-1300 °C for 2-4 h to finally repair the defects in the SiC ceramic matrix composite material.

2. The rapid repair method for damage defects in SiC ceramic matrix composite materials according to claim 1, characterized in that, The SiC ceramic matrix composite material mentioned in step (1) is one of C / SiC composite material and SiC / SiC composite material.

3. The rapid repair method for damage defects in SiC ceramic matrix composite materials according to claim 1, characterized in that, The SiC nanowire catalyst mentioned in step (2) is one of metallic iron, metallic nickel, ferric nitrate, nickel nitrate, and ferrocene.

4. The rapid repair method for damage defects in SiC ceramic matrix composite materials according to claim 1, characterized in that, The dispersant mentioned in step (2) is one of the following: arabic resin, sodium tripolyphosphate, sodium polyacrylate, sodium hexametaphosphate, and sodium citrate.

5. A rapid repair method for damage defects in SiC ceramic matrix composite materials according to claim 1, characterized in that, The defects in the SiC ceramic matrix composite material mentioned in step (2) are one of the following: cracks, delamination, and spalling in the SiC ceramic matrix composite material.

6. The rapid repair method for damage defects in SiC ceramic matrix composite materials according to claim 1, characterized in that, The polymer precursor solution mentioned in step (5) is one of polysilane, polycarbosilane, polysilazane, and polysiloxane.