A method for impregnating ceramic powder into fiber bundles

Abstract

The present invention relates to a method for impregnating ceramic powder in a fiber bundle, which comprises providing an impregnation slurry and a fiber preform to be impregnated respectively, wherein the impregnation slurry is provided by dispersing ceramic powder in a solvent, and the fiber preform to be impregnated is provided by ultrasonically dispersing the fiber bundle in a medium to disperse adjacent fibers in the fiber bundle, the power of ultrasonic dispersion is 20kw~50kw, and the frequency of ultrasonic dispersion is 50kHz~120kHz; the fiber preform to be impregnated is placed in the impregnation slurry for ultrasonic impregnation to introduce the ceramic powder into the fiber bundle, wherein the power of ultrasonic impregnation is 1kw~20kw, and the frequency of ultrasonic impregnation is 10kHz~100kHz; the impregnated fiber preform is naturally dried to form a fiber impregnation material structure in which the ceramic powder is uniformly filled in the fiber bundle. The method for impregnating ceramic powder in a fiber bundle according to the present invention is efficient, energy-saving, environmentally friendly, and easy to operate.

Description

Technical Field

[0001] The invention relates to a ceramic-based composite material, and more particularly to a method for impregnating ceramic powder into a fiber bundle. Background Art

[0002] Ceramic-based composites can be widely used in working conditions where organic-based and metal-based composites cannot meet performance requirements, and become ideal high-temperature structural materials. They are mainly used as machining materials, wear-resistant materials, high-temperature engine combustion chambers and connecting rods, spacecraft protection materials, high-temperature heat exchanger materials, high-temperature corrosion-resistant materials, light armor materials, separation or filter materials, load-bearing / wave-transmitting / heat-insulating materials, etc. Ceramic-based composites are the preferred materials for future engine hot end structures and can replace metals and their alloys.

[0003] In the existing ceramic matrix composite material preparation process, the presence of micron-sized pores in the fiber bundle is often not conducive to matrix filling. In the commonly used preparation process, the precursor impregnation pyrolysis method (PIP) can impregnate the solution into the fiber bundle under the action of capillary force, and form the matrix in situ in the fiber bundle through high-temperature heat treatment. However, the PIP process has the following shortcomings. The first is the problem of raw materials involved in the precursor, that is, the types of precursors are limited, and there is no universality to introduce various different materials into the micropores of the fiber bundle. The second is the low introduction efficiency, which is inefficient due to the low yield of precursor pyrolysis. It usually requires repeated impregnation-pyrolysis processes to densify the material. Summary of the invention

[0004] In order to solve the problems of universality and inefficiency in the above-mentioned prior art, the present invention provides a method for impregnating ceramic powder into a fiber bundle.

[0005] According to the method for impregnating ceramic powder in a fiber bundle of the present invention, it includes the following steps: S1, respectively providing an impregnation slurry and a fiber preform to be impregnated, wherein the impregnation slurry is provided by dispersing ceramic powder in a solvent, and the fiber preform to be impregnated is provided by ultrasonically dispersing the fiber bundle in a medium to disperse adjacent fibers in the fiber bundle, the power of ultrasonic dispersion is 20kw~50kw, and the frequency of ultrasonic dispersion is 50kHz~120kHz; S2, placing the fiber preform to be impregnated in the impregnation slurry for ultrasonic impregnation to introduce the ceramic powder into the fiber bundle, wherein the power of ultrasonic impregnation is 1kw~20kw, and the frequency of ultrasonic impregnation is 10kHz~100kHz; and S3, the impregnated fiber preform is naturally dried to form a fiber impregnation material structure in which the ceramic powder is uniformly filled in the fiber bundle.

[0006] In a preferred embodiment, ceramic powder is poured into a solvent to form a mixed solution, and after stirring, electromagnetic wave ultrasound is used to disperse the soft agglomerated ceramic powder to provide an impregnation slurry.

[0007] In a preferred embodiment, the ceramic powder is SiC, ZrC, HfC, HfB2, ZrB2, RE2Si2O7, or RE2O3.

[0008] In a preferred embodiment, the mass of the ceramic powder is 5% to 20% of the mass of the impregnation slurry.

[0009] In a preferred embodiment, the impregnation slurry also includes a dispersant.

[0010] In a preferred embodiment, the dispersant is polyethyleneimine, triethylamine, or triethanolamine.

[0011] In a preferred embodiment, the mass of the dispersant is 0.1% to 5% of the mass of the impregnation slurry.

[0012] In a preferred embodiment, the power of ultrasonic dispersion is 30 kW to 40 kW, and the frequency of ultrasonic dispersion is 40 kHz to 80 kHz.

[0013] In a preferred embodiment, the impregnated fiber preform is placed flat on a flat plate and dried naturally to form a fiber impregnation material structure in which the ceramic powder is uniformly filled in the fiber bundles.

[0014] In a preferred embodiment, the fiber prepreg structure increases in weight by 172% to 397% relative to the fiber preform.

[0015] According to the method for impregnating ceramic powder in a fiber bundle of the present invention, the matrix can be efficiently introduced into the fiber bundle, and it is universal for various matrix materials, while greatly reducing energy consumption and being environmentally friendly. In short, according to the method for impregnating ceramic powder in a fiber bundle of the present invention, it is efficient, energy-saving, environmentally friendly, and easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a SEM image showing that HfB2 is fully filled in the fiber bundle after ultrasonic impregnation according to Example 1 of the present invention. DETAILED DESCRIPTION

[0017] The preferred embodiments of the present invention are given below in conjunction with the accompanying drawings and described in detail.

[0018] The method for impregnating ceramic powder in a fiber bundle according to the present invention first comprises step S1 of providing an impregnation slurry and a fiber preform to be impregnated respectively.

[0019] The impregnation slurry is provided by dispersing the ceramic powder in the solvent. In a preferred embodiment, the ceramic powder is poured into the solvent to form a mixed solution, and after stirring, the soft agglomerated ceramic powder is dispersed by electromagnetic wave ultrasound to provide an impregnation slurry. In a preferred embodiment, the ceramic powder includes but is not limited to SiC, ZrC, HfC, HfB2, ZrB2, RE2Si2O7, RE2O3, etc. The particle size of the ceramic powder is 10nm~100μm. In a preferred embodiment, the particle size of the ceramic powder is 0.5μm. In a preferred embodiment, the particle size of the ceramic powder is 10μm. In a preferred embodiment, the particle size of the ceramic powder is 0.5μm~10μm. In a preferred embodiment, the solvent includes but is not limited to deionized water, ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, acetone, etc. In a preferred embodiment, the solvent is deionized water. In a preferred embodiment, the mass of the ceramic powder in the impregnation slurry is less than 40% of the mass of the solvent. In a preferred embodiment, the mass of the ceramic powder is 5% to 20% of the mass of the impregnation slurry. In a preferred embodiment, the impregnation slurry also includes a dispersant. In a preferred embodiment, the dispersant includes but is not limited to polyethyleneimine, triethylamine, triethanolamine, etc. In a preferred embodiment, the mass of the dispersant is less than 10% of the mass of the impregnation slurry. In a preferred embodiment, the mass of the dispersant is 0.1% to 5% of the mass of the impregnation slurry.

[0020] The fiber preform to be impregnated is provided by ultrasonically dispersing the fiber bundle in the medium to disperse the adjacent fibers in the fiber bundle, wherein the power of ultrasonic dispersion is 20kw~50kw and the frequency of ultrasonic dispersion is 50kHz~120kHz. In a preferred embodiment, an interface is prepared on the fiber surface to form a fiber preform, and the fibers in the fiber preform are dispersed by ultrasound, and then dried to form a fiber preform to be impregnated. In a preferred embodiment, the interface is prepared on the fiber surface by chemical vapor deposition process. In a preferred embodiment, the thickness of the interface is 200nm~800nm. In a preferred embodiment, the fiber includes but is not limited to carbon fiber, SiC fiber, etc. In a preferred embodiment, the medium is alcohol. In a preferred embodiment, the power of ultrasonic dispersion is 30kw~40kw. In a preferred embodiment, the power of ultrasonic dispersion is 35kw. In a preferred embodiment, the frequency of ultrasonic dispersion is 40kHz~80kHz. In a preferred embodiment, the frequency of ultrasonic dispersion is 50kHz. In a preferred embodiment, the time of ultrasonic dispersion is 1min~10min. In a preferred embodiment, the time of ultrasonic dispersion is 5min~10min.

[0021] The method for impregnating ceramic powder in a fiber bundle according to the present invention then includes step S2, placing the fiber preform to be impregnated into the impregnation slurry for ultrasonic impregnation to introduce the ceramic powder into the fiber bundle, wherein the power of the ultrasonic impregnation is 1kw~20kw, and the frequency of the ultrasonic impregnation is 10kHz~100kHz. In a preferred embodiment, the power of the ultrasonic impregnation is 1kw~10kw. In a preferred embodiment, the power of the ultrasonic impregnation is 5kw. In a preferred embodiment, the frequency of the ultrasonic impregnation is 20kHz~40kHz. In a preferred embodiment, the frequency of the ultrasonic impregnation is 25kHz. In a preferred embodiment, the time of ultrasonic impregnation is 1min~10min. In a preferred embodiment, the time of ultrasonic impregnation is 2min~5min.

[0022] The method for impregnating ceramic powder in a fiber bundle according to the present invention finally includes step S3, wherein the impregnated fiber preform is naturally dried to form a fiber impregnation structure in which the ceramic powder is uniformly filled in the fiber bundle. In a preferred embodiment, the impregnated fiber preform is placed flat on a flat plate and naturally dried to form a fiber impregnation structure in which the ceramic powder is uniformly filled in the fiber bundle. In a preferred embodiment, the fiber impregnation structure gains 172% to 397% weight relative to the fiber preform. In a preferred embodiment, the fiber impregnation structure gains 195% to 321% weight relative to the fiber preform. In a preferred embodiment, the fiber impregnation structure gains 215% to 278% weight relative to the fiber preform. In a preferred embodiment, the fiber impregnation structure gains 247% weight relative to the fiber preform.

[0023] Example 1.

[0024] Using 95g deionized water as solvent, pour 5g HfB2 powder into deionized water. The particle size of HfB2 powder is 0.5μm. Use a magnetic stirrer to stir the mixed solution for 20min, and then use electromagnetic wave ultrasound for 10min to disperse the soft agglomerated HfB2 to form an impregnation slurry to be used.

[0025] The carbon fiber sheets were cut into 10mm×25mm, and a 200nm~800nm ​​interface for improving the mechanical properties / anti-oxidation properties was prepared on the fiber surface by chemical vapor deposition process to form a fiber preform. Then, alcohol was used as the medium and ultrasonic impregnation was used to disperse the adjacent fibers in the fiber bundle in the fiber preform. The power was 35kw and the frequency was 50kHz, and the ultrasonic dispersion was performed for 5 minutes, and then the fiber preform to be impregnated was formed by drying.

[0026] The fiber preform to be impregnated is placed in the impregnation slurry and ultrasonically impregnated for 2 minutes at a power of 5 kW and a frequency of 25 kHz.

[0027] The impregnated fiber preform is placed flat on a flat plate and dried naturally to form a fiber impregnation structure with uniform filling in the fiber bundle. The weight gain of the impregnated slurry is 278% through measurement. The SEM image after ultrasonic impregnation is as follows Figure 1 As shown, after ultrasonic impregnation, HfB2 was fully filled in the fiber bundle.

[0028] Example 2.

[0029] 80 g of deionized water was used as the solvent, 20 g of HfC was used as the impregnation powder, the particle size was 10 μm, and other conditions were the same as in Example 1. After ultrasonic impregnation, the material gained 397% in weight.

[0030] Example 3.

[0031] The ultrasonic dispersion power was 40 kW, the ultrasonic dispersion was 80 kHz, the ultrasonic time was 10 min, the ultrasonic immersion power was 1 kW, the ultrasonic frequency was 20 kHz, the ultrasonic time was 5 min, and the other conditions were the same as those in Example 1. After ultrasonic immersion, the material gained 247%.

[0032] Example 4.

[0033] The ultrasonic immersion power was 10 kW, the ultrasonic frequency was 40 kHz, the ultrasonic time was 2 min, and the other conditions were the same as those in Example 1. After ultrasonic immersion, the weight of the material increased by 321%.

[0034] Example 5.

[0035] 95 g of deionized water was used as the solvent, 5 g of RE2Si2O7 was used as the impregnating material, 0.1 g of polyethyleneimine was used as the dispersant, SiC fiber was used as the impregnating fiber, and other conditions were the same as those in Example 1. The weight gain of the impregnated slurry was measured to be 172%.

[0036] Example 6.

[0037] 80g of anhydrous ethanol was used as the solvent, 20g of RE2Si2O7 was used as the impregnating material, 5g of triethylamine was used as the dispersant, SiC fiber was used as the impregnating fiber, and other conditions were the same as those in Example 1. The weight gain of the impregnated slurry was measured to be 215%.

[0038] Example 7.

[0039] After the fibers were cut, no prior ultrasound was used to separate the fibers. Other conditions were the same as in Example 1. The weight gain of the impregnated slurry was measured to be 195%.

[0040] Obviously, the method for impregnating ceramic powder into fiber bundles according to the present invention is not the common pure liquid phase impregnation, but solid phase impregnation, which does not require vacuum assistance. The powder particles can be effectively introduced into the fiber bundle by adjusting the ultrasonic impregnation method.

[0041] The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The above embodiment of the present invention can also be modified in various ways. That is, all simple, equivalent changes and modifications made according to the claims and the description of the present invention fall within the scope of protection of the claims of the present invention. The contents not described in detail in the present invention are all conventional technical contents.

Claims

1. A method for impregnating ceramic powder into a fiber bundle, characterized in that: The method comprises the following steps: S1, respectively providing an impregnation slurry and a fiber preform to be impregnated, wherein the impregnation slurry is provided by dispersing a ceramic powder in a solvent; in a medium, using ultrasound to disperse adjacent fibers in a fiber bundle in the fiber preform, and then drying to form a fiber preform to be impregnated, wherein the power of the ultrasonic dispersion is 20kw~50kw, and the frequency of the ultrasonic dispersion is 50kHz~120kHz; S2, placing the fiber preform to be impregnated into the impregnation slurry for ultrasonic impregnation to introduce the ceramic powder into the fiber bundle, wherein the power of the ultrasonic impregnation is 1kw~20kw, and the frequency of the ultrasonic impregnation is 10kHz~100kHz; and S3, the impregnated fiber preform is naturally dried to form a fiber impregnation material structure in which the ceramic powder is uniformly filled in the fiber bundle; The mass of ceramic powder is 5%~20% of the mass of impregnation slurry; The fiber prepreg structure increases in weight by 172% to 397% relative to the fiber preform.

2. The method according to claim 1, characterized in that The ceramic powder is poured into a solvent to form a mixed liquid, and after stirring, electromagnetic wave ultrasound is used to disperse the soft agglomerated ceramic powder to provide an impregnation slurry.

3. The method according to claim 1, characterized in that The ceramic powder is SiC, ZrC, HfC, HfB2, ZrB2, RE2Si2O7 or RE2O3.

4. The method according to claim 1, characterized in that: The impregnation slurry also includes a dispersant.

5. The method according to claim 4, characterized in that The dispersant is polyethyleneimine, triethylamine or triethanolamine.

6. The method according to claim 4, characterized in that The mass of the dispersant is 0.1% to 5% of the mass of the impregnation slurry.

7. The method according to claim 1, characterized in that The power of ultrasonic dispersion is 30kw~40kw, and the frequency of ultrasonic dispersion is 40kHz~80kHz.

8. The method according to claim 1, characterized in that The impregnated fiber preform is placed flat on a flat plate and dried naturally to form a fiber impregnation material structure in which the fiber bundles are uniformly filled with ceramic powder.

Images