Brake material for carbon-ceramic brake disc as well as preparation method and application of brake material

Abstract

The invention discloses a brake material for a carbon-ceramic brake disc and a preparation method and application of the brake material, and the brake material is prepared from organic resin, a curing agent, inorganic filler, a solvent and a dispersing agent according to the mass ratio of (100-130): (5-30): (10-20): (150-180): (6-8). The brake material for the carbon-ceramic brake disc is obtained by adopting a specific component proportion and combining hot-pressing curing, a chemical vapor infiltration method and graphitization treatment, so that the brake material has the characteristics of high strength, proper friction coefficient and low wear rate, and the wear resistance is improved.

Description

Technical Field

[0001] The present application relates to the technical field of brake materials, and in particular to a brake material for a carbon-ceramic brake disc and a preparation method and application thereof. Background Art

[0002] Carbon ceramic brake discs are reinforced with high-strength carbon fibers and are based on pyrolytic carbon, silicon carbide (SiC), etc. The role of carbon fibers is to improve the mechanical strength of the material and provide the material with the fracture toughness required in technical applications, while silicon carbide determines the hardness of the composite material. This structure gives carbon ceramic brake discs excellent physical properties and mechanical strength. They are often used in the braking systems of aircraft and other aircraft to meet the braking requirements under extreme conditions such as high temperature and high pressure. Braking materials are precursor materials for preparing carbon ceramic brake discs. The existing wear resistance is low and it is difficult to meet the material performance requirements in the field of high-performance braking and aerospace structural parts. Summary of the invention

[0003] The purpose of the present invention is to provide a brake material for carbon ceramic brake discs and a preparation method and application thereof. By adopting specific raw material components and improving the preparation process, the wear resistance of the final brake material is enhanced, solving the problem of low wear resistance in the prior art.

[0004] In order to solve the above technical problems, the present invention adopts the following solutions:

[0005] A method for preparing a brake material for a carbon-ceramic brake disc, characterized in that it comprises the following steps:

[0006] Step 1, preparing ceramic slurry: obtaining various raw material components according to mass ratio and mixing them evenly;

[0007] Step 2, preparing a preform: placing a plurality of monofilament carbon fibers in a ceramic slurry and dipping them multiple times, and then winding them to obtain a non-woven fabric; stacking and sewing the non-woven fabric and a mesh tire to obtain a preform;

[0008] Step three, subjecting the preform to hot pressing curing, densification and graphitization treatments to obtain a brake material for a carbon-ceramic brake disc.

[0009] The present invention adopts a specific component ratio combined with hot pressing curing, chemical vapor infiltration and graphitization treatment, and is based on multiple immersion in ceramic slurry to obtain a brake material for a carbon-ceramic brake disc, so that the brake material has the characteristics of high strength, appropriate friction coefficient, low wear rate, and improved wear resistance.

[0010] Further, the raw material components include organic resin, curing agent, inorganic filler, solvent and dispersant, and the mass ratio is 100-130:5-30:10-20:150-180:6-8;

[0011] Furthermore, the organic resin is one or both of phenolic resin and epoxy resin;

[0012] The curing agent is one or more of urotropine, m-phenylenediamine and polyamide;

[0013] The inorganic filler is one or more of flake graphite, silicon carbide powder and aluminum powder;

[0014] The solvent is one or more of ethanol, acetone and water;

[0015] The dispersant is sodium carboxymethyl cellulose.

[0016] Furthermore, in the step 2, the immersion time is 5 to 15 minutes, the immersion temperature is room temperature, and the immersion pressure is 0.3 to 0.5 MPa.

[0017] Furthermore, the dipping is performed 2 to 5 times.

[0018] Furthermore, the sewing adopts Z-direction needling or through-sewing.

[0019] Furthermore, in step three, the temperature of the hot pressing curing treatment is 180-250° C., the pressure is 3-10 MPa, and the time is 1.5-3 h. The carbon / carbon embryo is sintered at 900-1200° C. for 1.5-3 h.

[0020] Furthermore, the sintered carbon / carbon embryo is densified to a density of 1.3-1.5 g / cm by chemical vapor infiltration at 800-1000° C. with the carbon source gas being propylene, liquefied petroleum gas or natural gas and the carrier gas being hydrogen, nitrogen or argon. 3 .

[0021] Furthermore, the graphitization treatment is carried out under vacuum conditions at 2300-2700° C. for 1-3 hours.

[0022] A brake material for a carbon-ceramic brake disc is prepared by adopting the above-mentioned method for preparing the brake material.

[0023] An application of the above-mentioned brake material in the field of braking or aerospace structural parts.

[0024] The beneficial effects of the present invention are as follows: the present invention adopts a specific component ratio combined with hot pressing curing, chemical vapor infiltration and graphitization treatment, and adopts multiple impregnations of ceramic slurry to prepare a preform, and finally obtains a brake material for a carbon-ceramic brake disc, so that the brake material has the characteristics of high strength, suitable friction coefficient and low wear rate, improves wear resistance, and meets the requirements for material performance in the field of high-performance braking and aerospace structural parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the process flow of the method for preparing the brake material in the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Technologies, methods, and apparatus known to ordinary technicians in the relevant field may not be discussed in detail, but where appropriate, such technologies, methods, and apparatus should be considered part of the authorization specification.

[0028] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0029] Example 1

[0030] This embodiment is a method for preparing a brake material for a carbon ceramic brake disc. Figure 1 , including the following steps:

[0031] (1) Preparation of ceramic slurry: Organic resin, curing agent, inorganic filler, solvent and sodium carboxymethyl cellulose in a mass ratio of 115:15:15:160:6 were uniformly mixed to prepare ceramic slurry.

[0032] The organic resin is phenolic resin, the curing agent is hexamethylenetetramine, the inorganic filler is a mixture of flake graphite, silicon carbide powder and aluminum powder (mass ratio is 1.2:1.5:1), and the solvent is ethanol and acetone (mass ratio is 1:1).

[0033] (2) Preparing a preform: impregnating a plurality of monofilament carbon fibers in a ceramic slurry for 15 minutes at room temperature and at a pressure of 0.3 MPa. After impregnation for three times, the non-woven fabric is wound to obtain a non-woven fabric; the non-woven fabric and the mesh are stacked and laid by Z-axis needle punching or through-sewing to obtain a preform.

[0034] (3) The preform is subjected to hot pressing curing treatment, densification treatment and graphitization treatment in sequence to obtain a brake material for a carbon-ceramic brake disc.

[0035] The preform was hot-pressed and cured at 200°C and 7MPa for 1.5h, and then sintered at 1100°C for 1.5h to obtain a carbon / carbon body with a density of 1.25g / cm 3 The carbon / carbon body was then densified to a density of 1.45 g / cm by chemical vapor infiltration at 900 °C with propylene as the carbon source gas and argon as the carrier gas. 3 , and then graphitized at 2600℃ under vacuum conditions for 2h to obtain the brake material for carbon-ceramic brake discs.

[0036] Example 2

[0037] This embodiment is a method for preparing a brake material for a carbon-ceramic brake disc, comprising the following steps:

[0038] (1) Preparation of ceramic slurry: Organic resin, curing agent, inorganic filler, solvent and sodium carboxymethyl cellulose in a mass ratio of 110:20:15:150:8 were uniformly mixed to prepare ceramic slurry.

[0039] Among them, the organic resin is phenolic resin and epoxy resin (mass ratio is 1:1.3), the curing agent is urotropine and meta-phenylenediamine (mass ratio is 1:1.5), the inorganic filler is a mixture of flake graphite, silicon carbide powder and aluminum powder (mass ratio is 1.2:1.5:1), and the solvent is ethanol and acetone (mass ratio is 1:1).

[0040] (2) Preparing a preform: a plurality of single-filament carbon fibers are immersed in a ceramic slurry for 5 minutes at room temperature and at a pressure of 0.4 MPa. After immersion for 5 times, the preform is wound to obtain a non-woven fabric; the non-woven fabric and the mesh are stacked and laid, and Z-direction needle punching is performed to obtain a preform.

[0041] (3) The preform is subjected to hot pressing curing treatment, densification treatment and graphitization treatment in sequence to obtain a brake material for a carbon-ceramic brake disc.

[0042] The preform was hot-pressed and cured for 2 h at 180 °C and 5 MPa, and then sintered for 3 h at 1000 °C to obtain a carbon / carbon body with a density of 1.30 g / cm 3 The carbon / carbon body was then densified to a density of 1.5 g / cm by chemical vapor infiltration at 1000 °C with liquefied petroleum gas as the carbon source gas and nitrogen as the carrier gas. 3 , and then graphitized at 2400℃ under vacuum conditions for 1h to obtain the brake material for carbon-ceramic brake discs.

[0043] Example 3

[0044] This embodiment is a method for preparing a brake material for a carbon-ceramic brake disc, comprising the following steps:

[0045] (1) Preparation of ceramic slurry: Organic resin, curing agent, inorganic filler, solvent and sodium carboxymethyl cellulose in a mass ratio of 125:25:15:170:8 were uniformly mixed to prepare ceramic slurry.

[0046] Among them, the organic resin is epoxy resin, the curing agent is a mixture of urotropine, meta-phenylenediamine and polyamide (mass ratio is 1:1.5:1.3), the inorganic filler is a mixture of aluminum powder and silicon carbide powder (mass ratio is 1.2:1), and the solvent is water, ethanol and acetone (mass ratio is 1:1:1).

[0047] (2) Preparing a preform: a plurality of monofilament carbon fibers are immersed in a ceramic slurry for 10 minutes at room temperature and a pressure of 0.5 MPa. After immersion for 4 times, the non-woven fabric is obtained by winding; the non-woven fabric and the mesh are stacked and laid by cross-sewing to obtain a preform.

[0048] (3) The preform is subjected to hot pressing curing treatment, densification treatment and graphitization treatment in sequence to obtain a brake material for a carbon-ceramic brake disc.

[0049] The preform was hot-pressed and cured at 240°C and 7MPa for 1.5h, and then sintered at 1000°C for 3h to obtain a carbon / carbon body with a density of 1.43g / cm 3 The carbon / carbon body was then densified to a density of 1.45 g / cm by chemical vapor infiltration at 1000 °C with propylene as the carbon source gas and hydrogen as the carrier gas. 3 , and then graphitized at 2400℃ under vacuum conditions for 3h to obtain the brake material for carbon-ceramic brake discs.

[0050] Example 3

[0051] This embodiment is a method for preparing a brake material for a carbon-ceramic brake disc, comprising the following steps:

[0052] (1) Preparation of ceramic slurry: Organic resin, curing agent, inorganic filler, solvent and sodium carboxymethyl cellulose in a mass ratio of 130:25:20:170:8 were uniformly mixed to prepare ceramic slurry.

[0053] Among them, the organic resin is epoxy resin, the curing agent is a mixture of urotropine, meta-phenylenediamine and polyamide (mass ratio is 1:1.5:1.3), the inorganic filler is a mixture of aluminum powder and silicon carbide powder (mass ratio is 1.2:1), and the solvent is water and ethanol (mass ratio is 1:1).

[0054] (2) Preparing a preform: a plurality of single-filament carbon fibers are immersed in a ceramic slurry for 15 minutes at room temperature and a pressure of 0.5 MPa. After two immersions, the preform is wound to obtain a non-woven fabric; the non-woven fabric and the mesh are stacked and laid, and Z-direction needle punching is performed to obtain a preform.

[0055] (3) The preform is subjected to hot pressing curing treatment, densification treatment and graphitization treatment in sequence to obtain a brake material for a carbon-ceramic brake disc.

[0056] The preform was hot-pressed and cured at 220°C and 10 MPa for 2 h, and then sintered at 1200°C for 1.5 h to obtain a carbon / carbon body with a density of 1.43 g / cm 3 The carbon / carbon body was then densified to a density of 1.5 g / cm by chemical vapor infiltration at 1200 °C with natural gas as the carbon source gas and helium as the carrier gas. 3 , and then graphitized at 2500℃ under vacuum conditions for 3h to obtain the brake material for carbon-ceramic brake discs.

[0057] Comparative Example

[0058] The components and methods of this comparative example are consistent with those of Example 2, except that the ceramic slurry is sprayed onto the surface of the monofilament carbon fiber in the comparative example.

[0059] The brake materials prepared in Example 2 and the comparative example were tested for mechanical properties and friction and wear. The results are shown in Table 1 below.

[0060] <![CDATA[Density (g / cm 3 )]]> Bending strength / MPa Dynamic friction coefficient Wear rate coefficient / (μm / time) Example 2 1.5 297 0.32 0.39 Comparative Example 1.46 239 0.42 0.53

[0061] As shown in Table 1, by comparing the material performance test results of the examples and comparative samples, the present application adopts the method of multiple impregnation of monofilament carbon fiber to prepare the preform, so that the finally prepared brake material has the characteristics of high strength, suitable friction coefficient and low wear rate; and the subsequently prepared carbon ceramic brake disc finished product meets the requirements of high performance braking.

[0062] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a brake material for a carbon-ceramic brake disc, characterized in that: The following steps are involved: Step 1, preparing ceramic slurry: obtaining various raw material components according to mass ratio and mixing them evenly; Step 2, preparing a preform: placing a plurality of monofilament carbon fibers in a ceramic slurry and dipping them multiple times, and then winding them to obtain a non-woven fabric; stacking and sewing the non-woven fabric and a mesh tire to obtain a preform; Step three, subjecting the preform to hot pressing curing, densification and graphitization treatments to obtain a brake material for a carbon-ceramic brake disc.

2. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 1, characterized in that: The raw material components include organic resin, curing agent, inorganic filler, solvent and dispersant, and the mass ratio is 100-130:5-30:10-20:150-180:6-8; The organic resin is one or both of phenolic resin and epoxy resin; The curing agent is one or more of urotropine, m-phenylenediamine and polyamide; The inorganic filler is one or more of flake graphite, silicon carbide powder and aluminum powder; The solvent is one or more of ethanol, acetone and water; The dispersant is sodium carboxymethyl cellulose.

3. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 1, characterized in that: In the step 2, the immersion time is 5 to 15 minutes, the immersion temperature is room temperature, and the immersion pressure is 0.3 to 0.5 MPa.

4. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 1, characterized in that: The number of times of immersion is 2 to 5 times.

5. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 1, characterized in that: The sewing is performed by Z-direction needle punching or through-sewing.

6. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 1, characterized in that: In the step three, the temperature of the hot pressing curing treatment is 180-250° C., the pressure is 3-10 MPa, and the time is 1.5-3 h. The carbon / carbon embryo is then sintered at 900-1200° C. for 1.5-3 h.

7. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 6, characterized in that: The sintered carbon / carbon embryo is densified to a density of 1.3-1.5 g / cm by chemical vapor infiltration at 800-1000°C with propylene, liquefied petroleum gas or natural gas as the carbon source gas and hydrogen, nitrogen or argon as the carrier gas. 3 .

8. The method for preparing a brake material for a carbon-ceramic brake disc according to claim 6, characterized in that: The graphitization treatment is carried out under vacuum conditions at 2300-2700° C. for 1-3 hours.

9. A brake material for a carbon ceramic brake disc, characterized in that: The brake material is prepared by the method for preparing the brake material according to any one of claims 1 to 8.

10. Use of the brake material according to any one of claims 1 or 2 in the field of braking or aerospace structural parts.

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