Disclosure of Invention
Technical problem to be solved
In order to avoid the defects of the prior art, the invention provides C/(Hf, Zr) C- (Hf, Zr) B2-SiC superhigh temperature ceramic matrix composite material and preparation method thereof, in-situ generation HfC-ZrC-HfB2-ZrB2-SiC multicomponent ablation-resistant matrix, in which HfC and ZrC constitute a (Hf, Zr) C solid solution, HfB2And ZrB2Composition (Hf, Zr) B2The solid solution effectively improves the oxidation and ablation resistance of the composite material. The obtained material has high density and good mechanical property, and the prepared composite material ultrahigh-temperature ceramic has high volume content of components, so that the process steps are reduced, and the cost is reduced.
Technical scheme
C/(Hf, Zr) C- (Hf, Zr) B2-SiC ultra high temperature ceramic matrix composite characterized by: introducing B into pores of C/C composite material preform4C and C, and silicon-hafnium alloy and silicon-zirconium alloy; the mass ratio of the silicon-hafnium alloy to the silicon-zirconium alloy is 1.5-2.5: 1.
The mass fraction of each component of the silicon-hafnium alloy powder is 70-75 wt% of Hf and 25-30 wt% of Si.
The silicon-zirconium alloy powder comprises, by mass, 60-75 wt% of Zr and 25-40 wt% of Si.
The C organic precursor is phenolic resin, furan resin or silane resin.
Preparing the C/(Hf, Zr) C- (Hf, Zr) B2The method for preparing the-SiC superhigh temperature ceramic matrix composite material is characterized by comprising the following steps:
step 1, B4C, preparation of slurry: dissolving sodium carboxymethylcellulose in distilled water, stirring to dissolve, adding B4C powder is ball-milled for 24-48 h to obtain B4C, sizing agent; the mass fraction of sodium carboxymethylcellulose dissolved in distilled water is 0.5-1%, and B4The mass ratio of C to distilled water is 1-4: 10;
step 2, C, preparing an organic precursor solution: dissolving the organic precursor C and hexamethylenetetramine in absolute ethyl alcohol, uniformly stirring until the mixture is dissolved, and performing ball milling for 24-48 h to obtain an organic precursor C solution; the mass ratio of hexamethylene tetramine to the C organic precursor is 1:10, and the viscosity of the C organic precursor solution is controlled to be 20-200mPa.s through absolute ethyl alcohol;
step 3, preparing mixed alloy powder: mixing and ball-milling the silicon-hafnium alloy and the silicon-zirconium alloy in a mass ratio of 1.5-2.5: 1 for 24-36 h to obtain silicon-hafnium-silicon-zirconium alloy powder;
the mass fraction of each component in the silicon-hafnium alloy powder is 70-75 wt% of Hf and 25-30 wt% of Si;
the silicon-zirconium alloy powder comprises, by mass, 60-75 wt% of Zr and 25-40 wt% of Si;
and 4, step 4: the open porosity of the C/C composite material preform is 10 vol% to 40 vol%.
Step 5, vacuum pressure impregnation B4C, slurry: placing the C/C composite material prefabricated body into a vacuum pressure impregnation tank, firstly vacuumizing until the vacuum degree is-0.05 to-0.10 Mpa, keeping for 30 to 60 minutes, and then opening a slurry impregnation valve at the bottom of the tank body to enable the slurry prepared in the step 2B to be impregnated into the tank body4C, reversely sucking the slurry into the tank body, completely immersing the prefabricated body, closing the immersion valve, continuously keeping the vacuum degree of-0.05 to-0.10 Mpa for 30 to 60 minutes, and closing a vacuum system valve and a vacuum pump; opening the high-pressure valve, filling compressed gas into the impregnation tank, keeping the pressure in the tank body to be 0.8-1.0 Mpa, and maintaining the pressure for 30-60 minutes to finish the step B4C, dipping the slurry;
step 6, vacuum pressure impregnation of the organic precursor solution C: impregnating B prepared in step 54Placing the C/C composite material preform of C in a vacuum pressure impregnation tank, firstly vacuumizing the vacuum pressure impregnation tank until the vacuum degree is-0.05 to-0.10 Mpa, keeping the vacuum degree for 30 to 60 minutes, then opening a slurry impregnation valve at the bottom of the tank body, enabling the C organic precursor solution prepared in the step 3 to be sucked into the tank body and completely immerse the preform, closing the impregnation valve, then continuously keeping the vacuum degree for 30 to 60 minutes at-0.05 to-0.10 Mpa, and closing a vacuum system valve and a vacuum pump; opening a high-pressure valve, filling compressed gas into the impregnation tank, keeping the pressure in the tank body to be 0.8-1.0 Mpa for 30-60 minutes, and finishing the step CDipping the organic precursor solution;
step 7, curing and cracking: placing the impregnated preform in the step 6 in an oven for drying at 60-80 ℃, then curing at 150-200 ℃ for 1h, and then carrying out heat treatment at 900-1800 ℃ for 2h in an argon or vacuum environment to obtain C/B4A C-C composite material;
step 8, C/(Hf, Zr) C- (Hf, Zr) B2-preparation of SiC composite: embedding the material processed in the step 7 into silicon hafnium-silicon zirconium alloy powder, and infiltrating the silicon hafnium-silicon zirconium alloy powder into C/B in a vacuum environment at the temperature of 1700-4In the C-C composite material, heat preservation is carried out for 1-2h, and alloy melt and B are mixed4In-situ generation of HfC-ZrC-HfB by C-C reaction2-ZrB2-SiC multicomponent ablation-resistant matrix, in which HfC and ZrC constitute a (Hf, Zr) C solid solution, HfB2And ZrB2Composition (Hf, Zr) B2Obtaining C/(Hf, Zr) C- (Hf, Zr) B through solid solution2-SiC ultra high temperature ceramic matrix composite.
The pretreatment of the C/C composite material preform is as follows: ultrasonically cleaning the C/C composite material preform for 1-2 hours, and drying in a forced air drying oven at 110-150 ℃ to obtain a dry and clean composite material preform.
The grain size of each different alloy powder in the step 3 is 30-80 μm.
B is4The particle size of the C powder is 0.5 to 1 μm.
The C/C composite material prefabricated body is a three-dimensional puncture, three-dimensional needling or two-dimensional laminated C/C composite material prefabricated body prepared by a chemical vapor infiltration or slurry impregnation cracking process.
Advantageous effects
The invention provides C/(Hf, Zr) C- (Hf, Zr) B2The preparation method of-SiC superhigh temperature ceramic matrix composite material is characterized by that in the C/C composite material prefabricated body B is introduced4C, and C organic precursor, curing and cracking to obtain C/B4A C-C preform. Then adopting reaction melt infiltration method to utilize silicon-hafnium alloy, silicon-zirconium alloy melt and B4C-C reaction to generate HfC-ZrC-HfB in situ2-ZrB2-a SiC multicomponent ablation-resistant matrix in which HfC and ZrC constitute a (Hf, Zr) C solid solution,HfB2and ZrB2Composition (Hf, Zr) B2The solid solution effectively improves the oxidation and ablation resistance of the composite material. The prepared composite material ultrahigh-temperature ceramic has high volume content and good mechanical property. The method adopts a vacuum-pressure impregnation method and is suitable for (Hf, Zr) C- (Hf, Zr) B2The preparation of the-SiC modified C/C and C/SiC composite material can effectively improve the ablation resistance of the composite material in an extreme environment.
(Hf, Zr) C- (Hf, Zr) B of the present invention2The SiC is used for modifying the C/C and C/SiC composite material, and the ablation resistance of the C/C and C/SiC composite material under extreme environments is improved. Simple preparation process, low requirement on equipment, low preparation cost and easy realization of C/(Hf, Zr) C- (Hf, Zr) B2And (3) rapidly preparing the-SiC ultrahigh-temperature ceramic matrix composite, wherein the porosity of the prepared composite is less than 8%, and the bending strength is more than 220 Mpa.
Detailed Description
The invention will now be further described with reference to the following examples and drawings:
C/(Hf,Zr)C-(Hf,Zr)B2the preparation steps of the-SiC superhigh temperature ceramic matrix composite material are as follows:
step 1, preparing a composite material preform: ultrasonically cleaning a C/C composite material preform with the open porosity of 10-40 vol% for 1-2 hours, and drying in a forced air drying oven at 110-150 ℃ to obtain a dry and clean composite material preform;
step 2, B4C, preparation of slurry: dissolving a certain amount of sodium carboxymethylcellulose in distilled water, stirring to dissolve, and adding a certain amount of B4C powder is ball-milled for 24-48 h to obtain B4C, sizing agent; the mass fraction of sodium carboxymethylcellulose dissolved in distilled water is 0.5-1%, and B4The mass ratio of C to distilled water is 1-4: 10;
step 3, C, preparing an organic precursor solution: dissolving a certain amount of C organic precursor and hexamethylenetetramine in absolute ethyl alcohol, uniformly stirring until the C organic precursor and the hexamethylenetetramine are dissolved, and performing ball milling for 24-48 h to obtain a C organic precursor solution; the mass ratio of hexamethylene tetramine to the C organic precursor is 1:10, and the viscosity of the C organic precursor solution is controlled to be 20-200mPa.s through absolute ethyl alcohol;
step 4, preparing mixed alloy powder: weighing different alloy powder with the particle size of 30-80 mu m, wherein the mass fraction of each component in the silicon-hafnium alloy powder is 70-75 wt% of Hf and 25-30 wt% of Si, and the mass fraction of each component in the silicon-zirconium alloy powder is 60-75 wt% of Zr and 25-40 wt% of Si; the sum of the mass fractions of the components in each alloy powder is 100%. And (3) mixing and ball-milling the weighed silicon-hafnium alloy powder and silicon-zirconium alloy powder for 24-36 h to obtain the silicon-hafnium-silicon-zirconium alloy powder. The mass ratio of the silicon-hafnium alloy to the silicon-zirconium alloy is 1.5-2.5: 1.
Step 5, vacuum pressure impregnation B4C, slurry: placing the C/C composite material prefabricated body into a vacuum pressure impregnation tank, firstly vacuumizing the C/C composite material prefabricated body until the vacuum degree is-0.05 to-0.10 Mpa, keeping the vacuum degree for a period of time, and then opening a slurry impregnation valve at the bottom of the tank body to ensure that the slurry impregnation valve at the bottom of the tank body prepared in the step 2 is opened to ensure that the slurry impregnation valve is positioned at the bottom of the tank body4C, reversely sucking the slurry into the tank body, completely immersing the prefabricated body, closing the immersion valve, continuously keeping the vacuum degree of-0.05 to-0.10 Mpa for a period of time, and closing a vacuum system valve and a vacuum pump; opening the high-pressure valve, filling compressed gas into the impregnation tank, keeping the pressure in the tank body to be 0.8-1.0 Mpa, and maintaining the pressure for a period of time to finish the step B4C, dipping the slurry; taking out the dip B4C, drying the sample of the slurry for later use;
step 6, vacuum pressure impregnation of the organic precursor solution C: impregnating B prepared in step 54Placing the C/C composite material prefabricated body of C in a vacuum pressure impregnation tank, firstly aligningVacuumizing until the vacuum degree is-0.05 to-0.10 Mpa, keeping for a period of time, then opening a slurry impregnation valve at the bottom of the tank body, sucking the organic precursor solution C prepared in the step 3 into the tank body in a pouring manner, completely immersing the prefabricated body, closing the impregnation valve, then continuously keeping the vacuum degree for a period of time of-0.05 to-0.10 Mpa, and closing a vacuum system valve and a vacuum pump; opening a high-pressure valve, filling compressed gas into the impregnation tank, keeping the pressure in the tank body to be 0.8-1.0 Mpa for a period of time, and finishing impregnation of the C organic precursor solution;
step 7, curing and cracking: placing the impregnated preform in the step 6 in an oven for drying at 60-80 ℃, then curing at 150-200 ℃ for 1h, and then carrying out heat treatment at 900-1800 ℃ for 2h in an argon or vacuum environment to obtain C/B4A C-C composite material;
step 8, C/(Hf, Zr) C- (Hf, Zr) B2-preparation of SiC composite: embedding the material processed in the step 7 into silicon hafnium-silicon zirconium alloy powder, and infiltrating the silicon hafnium-silicon zirconium alloy powder into the C/B obtained in the step 7 in a vacuum environment at the temperature of 1700-1800 DEG C4In the C-C composite material, heat preservation is carried out for 1-2h, and alloy melt and B are mixed4In-situ generation of HfC-ZrC-HfB by C-C reaction2-ZrB2-SiC multicomponent ablation-resistant matrix, in which HfC and ZrC constitute a (Hf, Zr) C solid solution, HfB2And ZrB2Composition (Hf, Zr) B2Obtaining C/(Hf, Zr) C- (Hf, Zr) B through solid solution2-SiC ultra high temperature ceramic matrix composite.
The C/C composite material prefabricated body is a three-dimensional puncture, three-dimensional needling or two-dimensional laminated C/C composite material prefabricated body prepared by a chemical vapor infiltration or slurry impregnation cracking process.
B is4The particle size of the C powder is 0.5 to 1 μm.
The C organic precursor is phenolic resin, furan resin or silane resin.
Example 1: preparation of C/(Hf, Zr) C- (Hf, Zr) B by using three-dimensional puncture C/C composite material2-SiC ultra high temperature ceramic matrix composite.
The preparation method comprises the following specific steps:
1. preparing a composite material preform: ultrasonically cleaning a three-dimensional puncture C/C composite material preform with an open pore rate of about 20 vol% for 1 hour, and drying the three-dimensional puncture C/C composite material preform in a forced air drying oven at 120 ℃ for 2 hours to obtain a dry and clean composite material preform;
2、B4c, preparation of slurry: dissolving a certain amount of sodium carboxymethylcellulose in distilled water, stirring to dissolve, and adding a certain amount of B4C powder is ball milled for 48 hours to obtain B4C, sizing agent; the mass fraction of sodium carboxymethylcellulose dissolved in distilled water is 0.5%, B4The mass ratio of C to distilled water is 1: 5;
3. preparing a phenolic resin solution: dissolving a certain amount of phenolic resin and hexamethylenetetramine in absolute ethyl alcohol, uniformly stirring until the phenolic resin and the hexamethylenetetramine are dissolved, and performing ball milling for 24 hours to obtain a phenolic resin solution; the mass ratio of hexamethylene tetramine to the phenolic resin is 1:10, and the viscosity of the phenolic resin solution is controlled to be 120mPa.s by absolute ethyl alcohol;
4. preparing mixed alloy powder: weighing different alloy powder with the grain diameter of about 45 mu m, wherein the mass fraction of each component in the silicon-hafnium alloy powder is 71 wt% of Hf and 29 wt% of Si, and the mass fraction of each component in the silicon-zirconium alloy powder is 62 wt% of Zr and 38 wt% of Si. And mixing and ball-milling the weighed silicon-hafnium alloy powder and silicon-zirconium alloy powder for 24 hours to obtain the silicon-hafnium-silicon-zirconium alloy powder. When the silicon-hafnium alloy powder and the silicon-zirconium alloy powder are weighed, the mass ratio of the silicon-hafnium alloy powder to the silicon-zirconium alloy powder is 1.6: 1.
5. Vacuum pressure impregnation B4C, slurry: placing the C/C composite material preform in a vacuum pressure impregnation tank, vacuumizing the vacuum pressure impregnation tank until the vacuum degree is-0.096 Mpa, keeping the vacuum pressure for 30min, and then opening a slurry impregnation valve at the bottom of the tank body to enable the slurry impregnation valve B prepared in the step 2 to be in a non-vacuum state4C, reversely sucking the slurry into the tank body, completely immersing the prefabricated body, closing the immersion valve, continuously keeping the vacuum degree of-0.096 Mpa, maintaining for 30min, and closing a vacuum system valve and a vacuum pump; opening the high pressure valve and charging the impregnation tank with compressed N2Maintaining the pressure in the tank body at 0.9MPa for 30min to complete the process B4C, dipping the slurry; taking out the dip B4C, drying the sample of the slurry for later use;
6. vacuum pressure impregnation of phenolic resin solution: impregnating B prepared in step 54Placing the C/C composite material prefabricated body of C in a vacuum pressure impregnation tank, firstly vacuumizing itKeeping the vacuum degree at-0.096 MPa for 30min, then opening a slurry impregnation valve at the bottom of the tank body, sucking the phenolic resin solution prepared in the step (3) into the tank body, completely immersing the prefabricated body, closing the impregnation valve, then continuously keeping the vacuum degree at-0.096 MPa, keeping the vacuum degree for 30min, and closing a vacuum system valve and a vacuum pump; opening the high pressure valve and charging the impregnation tank with compressed N2Keeping the pressure in the tank body to be 0.9Mpa for 30min to finish the impregnation of the phenolic resin solution;
7. curing and cracking: placing the impregnated preform in the step 6 in an oven to dry at 70 ℃, then curing at 170 ℃ for 1h, and then carrying out heat treatment at 1800 ℃ for 2h in a vacuum environment to obtain C/B4A C-C composite material;
8、C/(Hf,Zr)C-(Hf,Zr)B2-preparation of SiC composite: embedding the material processed in the step 7 into silicon hafnium-silicon zirconium alloy powder, and infiltrating the silicon hafnium-silicon zirconium alloy powder into the C/B obtained in the step 7 in a vacuum environment at the temperature of 1700-1800 DEG C4In the C-C composite material, heat preservation is carried out for 1h, and alloy melt and B are mixed4In-situ generation of HfC-ZrC-HfB by C-C reaction2-ZrB2-SiC multicomponent ablation-resistant matrix, in which HfC and ZrC constitute a (Hf, Zr) C solid solution, HfB2And ZrB2Composition (Hf, Zr) B2Obtaining C/(Hf, Zr) C- (Hf, Zr) B through solid solution2-SiC ultra high temperature ceramic matrix composite.
C/(Hf, Zr) C- (Hf, Zr) B prepared in example 12The content of carbon fiber in the-SiC superhigh temperature ceramic matrix composite material exceeds 60 vol%, and the apparent density is 2.79g/cm3The open porosity was about 6% and the bending strength was 265 MPa.
Example 2: preparation of C/(Hf, Zr) C- (Hf, Zr) B by using three-dimensional needling C/C composite material2-SiC ultra high temperature ceramic matrix composite.
The preparation method comprises the following specific steps:
1. preparing a composite material preform: ultrasonically cleaning a three-dimensional puncture C/C composite material preform with the air opening rate of about 30 vol% for 2 hours, and drying the three-dimensional puncture C/C composite material preform in a forced air drying oven at 150 ℃ for 1 hour to obtain a dry and clean composite material preform;
2、B4c, preparation of slurry: taking a certain amount of carboxymethyl celluloseDissolving sodium in distilled water, stirring to dissolve, adding a certain amount of B4C powder is ball milled for 48 hours to obtain B4C, sizing agent; the mass fraction of sodium carboxymethylcellulose dissolved in distilled water is 0.5%, B4The mass ratio of C to distilled water is 2: 5;
3. preparing a phenolic resin solution: dissolving a certain amount of phenolic resin and hexamethylenetetramine in absolute ethyl alcohol, uniformly stirring until the phenolic resin and the hexamethylenetetramine are dissolved, and performing ball milling for 24 hours to obtain a phenolic resin solution; the mass ratio of hexamethylene tetramine to the phenolic resin is 1:10, and the viscosity of the phenolic resin solution is controlled to be 145mPa.s by absolute ethyl alcohol;
4. preparing mixed alloy powder: weighing different alloy powder with the grain diameter of about 45 mu m, wherein the mass fraction of each component in the silicon-hafnium alloy powder is 75 wt% of Hf and 25 wt% of Si, and the mass fraction of each component in the silicon-zirconium alloy powder is 60 wt% of Zr and 40 wt% of Si. And mixing and ball-milling the weighed silicon-hafnium alloy powder and silicon-zirconium alloy powder for 24 hours to obtain the silicon-hafnium-silicon-zirconium alloy powder. When the silicon-hafnium alloy powder and the silicon-zirconium alloy powder are weighed, the mass ratio of the silicon-hafnium alloy powder to the silicon-zirconium alloy powder is 2: 1.
5. Vacuum pressure impregnation B4C, slurry: placing the C/C composite material preform in a vacuum pressure impregnation tank, vacuumizing the vacuum pressure impregnation tank until the vacuum degree is-0.096 Mpa, keeping the vacuum pressure for 30min, and then opening a slurry impregnation valve at the bottom of the tank body to enable the slurry impregnation valve B prepared in the step 2 to be in a non-vacuum state4C, reversely sucking the slurry into the tank body, completely immersing the prefabricated body, closing the immersion valve, continuously keeping the vacuum degree of-0.096 Mpa, maintaining for 30min, and closing a vacuum system valve and a vacuum pump; opening the high pressure valve and charging the impregnation tank with compressed N2Maintaining the pressure in the tank body at 0.9MPa for 30min to complete the process B4C, dipping the slurry; taking out the dip B4C, drying the sample of the slurry for later use;
6. vacuum pressure impregnation of phenolic resin solution: impregnating B prepared in step 54Placing the C/C composite material preform of C in a vacuum pressure impregnation tank, vacuumizing the vacuum pressure impregnation tank until the vacuum degree is-0.096 Mpa, keeping the vacuum degree for 30min, opening a slurry impregnation valve at the bottom of the tank body, sucking the phenolic resin solution prepared in the step (3) into the tank body in a pouring manner, completely immersing the preform, closing the impregnation valve, keeping the vacuum degree to-0.096 Mpa, keeping the vacuum degree for 30minVacuum system valves and vacuum pumps; opening the high pressure valve and charging the impregnation tank with compressed N2Keeping the pressure in the tank body to be 0.9Mpa for 30min to finish the impregnation of the phenolic resin solution;
7. curing and cracking: placing the impregnated preform in the step 6 in an oven for drying at 80 ℃, then curing at 200 ℃ for 1h, and then carrying out heat treatment at 900 ℃ for 2h under the protection of argon to obtain C/B4A C-C composite material;
8、C/(Hf,Zr)C-(Hf,Zr)B2-preparation of SiC composite: embedding the material processed in the step 7 into silicon hafnium-silicon zirconium alloy powder, and infiltrating the silicon hafnium-silicon zirconium alloy powder into the C/B obtained in the step 7 in a vacuum environment at the temperature of 1700-1800 DEG C4In the C-C composite material, the temperature is kept for 1.5h, and the alloy melt and the B are mixed4In-situ generation of HfC-ZrC-HfB by C-C reaction2-ZrB2-SiC multicomponent ablation-resistant matrix, in which HfC and ZrC constitute a (Hf, Zr) C solid solution, HfB2And ZrB2Composition (Hf, Zr) B2Obtaining C/(Hf, Zr) C- (Hf, Zr) B through solid solution2-SiC ultra high temperature ceramic matrix composite.
C/(Hf, Zr) C- (Hf, Zr) B prepared in example 22The content of carbon fiber in the-SiC superhigh temperature ceramic matrix composite material is about 40 vol%, and the apparent density is 2.81g/cm3The open porosity was about 8% and the bending strength was 227 MPa.
Example 3: preparation of C/(Hf, Zr) C- (Hf, Zr) B by two-dimensional laminated C/C composite material2-SiC ultra high temperature ceramic matrix composite.
The preparation method comprises the following specific steps:
1. preparing a composite material preform: ultrasonically cleaning a two-dimensional laminated C/C composite material preform with the open porosity of about 40 vol% for 2 hours, and drying the two-dimensional laminated C/C composite material preform in a forced air drying oven at 120 ℃ for 2 hours to obtain a dry and clean composite material preform;
2、B4c, preparation of slurry: dissolving a certain amount of sodium carboxymethylcellulose in distilled water, stirring to dissolve, and adding a certain amount of B4C powder is ball milled for 48 hours to obtain B4C, sizing agent; the mass fraction of sodium carboxymethylcellulose dissolved in distilled water is 0.5%, B4The mass ratio of C to distilled water is 2: 5;
3. preparation of furan resin solution: dissolving a certain amount of furan resin and hexamethylenetetramine in absolute ethyl alcohol, uniformly stirring until the furan resin and the hexamethylenetetramine are dissolved, and performing ball milling for 24 hours to obtain a furan resin solution; the mass ratio of hexamethylene tetramine to furan resin is 1:10, and the viscosity of the phenolic resin solution is controlled to be 145mPa.s by absolute ethyl alcohol;
4. preparing mixed alloy powder: weighing different alloy powder with the grain diameter of about 45 mu m, wherein the mass fraction of each component in the silicon-hafnium alloy powder is 70 wt% of Hf and 30 wt% of Si, and the mass fraction of each component in the silicon-zirconium alloy powder is 70 wt% of Zr and 30 wt% of Si. And mixing and ball-milling the weighed silicon-hafnium alloy powder and silicon-zirconium alloy powder for 24 hours to obtain the silicon-hafnium-silicon-zirconium alloy powder. When the silicon-hafnium alloy powder and the silicon-zirconium alloy powder are weighed, the mass ratio of the silicon-hafnium alloy powder to the silicon-zirconium alloy powder is 1.8: 1.
5. Vacuum pressure impregnation B4C, slurry: placing the C/C composite material preform in a vacuum pressure impregnation tank, vacuumizing to-0.096 Mpa, maintaining for 30min, and opening a slurry impregnation valve at the bottom of the tank body to enable the B to be immersed4C, reversely sucking the slurry into the tank body, completely immersing the prefabricated body, closing the immersion valve, continuously keeping the vacuum degree of-0.096 Mpa, maintaining for 30min, and closing a vacuum system valve and a vacuum pump; opening the high pressure valve and charging the impregnation tank with compressed N2Maintaining the pressure in the tank body at 0.9MPa for 30min to complete the process B4C, dipping the slurry; taking out the dip B4C, drying the sample of the slurry for later use;
6. vacuum pressure impregnation of furan resin solution: impregnating B prepared in step 54Placing the C/C composite material preform of C in a vacuum pressure impregnation tank, firstly vacuumizing the vacuum pressure impregnation tank until the vacuum degree is-0.096 Mpa, keeping the vacuum degree for 30min, then opening a slurry impregnation valve at the bottom of the tank body to suck furan resin solution into the tank body and completely immerse the preform, closing the impregnation valve, then continuously keeping the vacuum degree at-0.096 Mpa, keeping the vacuum degree for 30min, and closing a vacuum system valve and a vacuum pump; opening the high pressure valve and charging the impregnation tank with compressed N2Maintaining the pressure in the tank body to 0.9Mpa for 30min to finish the impregnation of the furan resin solution;
7. curing and cracking: placing the preform subjected to the impregnation in the step 6 in an oven at 80 DEG CDrying, curing at 200 deg.C for 1h, and heat treating at 900 deg.C under argon protection for 2h to obtain C/B4A C-C composite material;
8、C/(Hf,Zr)C-(Hf,Zr)B2-preparation of SiC composite: embedding the material processed in the step 7 into silicon hafnium-silicon zirconium alloy powder, and infiltrating the silicon hafnium-silicon zirconium alloy powder into the C/B obtained in the step 7 in a vacuum environment at the temperature of 1700-1800 DEG C4In the C-C composite material, heat preservation is carried out for 2 hours, and alloy melt and B are mixed4In-situ generation of HfC-ZrC-HfB by C-C reaction2-ZrB2-SiC multicomponent ablation-resistant matrix, in which HfC and ZrC constitute a (Hf, Zr) C solid solution, HfB2And ZrB2Composition (Hf, Zr) B2Obtaining C/(Hf, Zr) C- (Hf, Zr) B through solid solution2-SiC ultra high temperature ceramic matrix composite.
C/(Hf, Zr) C- (Hf, Zr) B prepared in example 32The content of carbon fiber in the-SiC superhigh temperature ceramic matrix composite material is about 40 vol%, and the apparent density is 2.84g/cm3The open porosity was about 7% and the bending strength was 231 MPa.
FIG. 1 shows C/(Hf, Zr) C- (Hf, Zr) B prepared by the present invention2The X-ray diffraction pattern of the-SiC superhigh temperature ceramic matrix composite material shows that HfC and ZrC have the same diffraction peak and HfB has the same diffraction peak as shown in figure 12、ZrB2The diffraction peaks are the same, the intensity of the diffraction peaks is high and sharp, and solid solutions of (Hf, Zr) C and (Hf, Zr) B are formed in the material2In addition, the high-intensity sharp beta-SiC diffraction peak is also present, which shows that (Hf, Zr) C solid solution and (Hf, Zr) B in the material2The solid solution and SiC have good crystallinity; the material also contains HfSi2、ZrSi2The alloy has the same diffraction peak, namely (Hf, Zr) Si is formed2Solid solution. As can be seen from FIG. 1, there are several ablation-resistant components in the material, (Hf, Zr) C, (Hf, Zr) B2SiC and (Hf, Zr) Si2The borosilicate glass protective layer can be formed by oxidation in the ablation process, absorbs heat and covers the surface of the material to prevent the material from being further damaged;
FIG. 2 shows C/(Hf, Zr) C- (Hf, Zr) B prepared by the present invention2And (3) scanning electron microscope photos of the section of the-SiC ultrahigh-temperature ceramic matrix composite, wherein a black area in the photos is a fiber bundle, and a white area is an ultrahigh-temperature ceramic phase. Ultra-high temperature ceramicThe phases are distributed among the fiber bundles in a large quantity and are compact, and the whole material has high compactness;
FIG. 3 and FIG. 4 show C/(Hf, Zr) C- (Hf, Zr) B prepared by the present invention2Back scattering electron pictures of medium and high power in section of-SiC ultrahigh temperature ceramic matrix composite, wherein bright white areas in the pictures are (Hf, Zr) C solid solution phases, and dark white areas are (Hf, Zr) B2Phase, dark gray areas as SiC phase, black areas as fiber bundles, (Hf, Zr) B in FIG. 42And is in dispersion distribution with SiC. A large amount of (Hf, Zr) C and (Hf, Zr) B are distributed in the material2The volume content of the anti-ablation component is high.