Carbon fiber friction material and preparation method thereof

Abstract

The invention discloses a carbon fiber friction material and a preparation method thereof, and belongs to the field of friction materials.The preparation method comprises the following steps that carbon fiber composite material regenerated particles, bonding phenolic resin, wollastonite fibers, silicon powder, ethyl alcohol and other raw materials are mixed, stirred and dried to obtain a prefabricated material, then mold pressing is conducted, and the carbon fiber friction material is obtained. The composite material obtained by the invention has good mechanical properties and friction resistance. The requirements of friction-resistant structure composite materials in the fields of automobiles, machinery, aviation, military and the like can be fully met.

Description

Technical Field

[0001] The invention belongs to the field of friction materials, and in particular relates to a carbon fiber friction material and a preparation method thereof. Background Art

[0002] Carbon-based friction materials are widely used in brake systems, seals, mechanical parts and other fields. They have attracted much attention due to their excellent wear resistance, high temperature performance and chemical corrosion resistance. However, conventional carbon-based friction materials have high rigidity and are easily damaged by friction and heat during the friction process.

[0003] In recent years, people have been committed to improving the performance of carbon-based friction materials, and one of the important methods is to add reinforcing materials. Fiber-reinforced materials have become one of the key reinforcing materials for improving carbon-based friction materials due to their high strength, high modulus and good mechanical properties. The use of carbon fiber to reinforce carbon-based friction materials can effectively improve the overall strength and hardness of the material, and improve its wear resistance and fatigue resistance. However, the existing carbon fiber friction materials have the following shortcomings: the interface bonding between the carbon fiber and the matrix is ​​insufficient, it is easy to peel off, the wear rate is high, and it is difficult to meet the needs of different application scenarios. Summary of the invention

[0004] In order to solve the problem of high wear rate of existing carbon fiber friction materials, the present invention provides a carbon fiber friction material and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A carbon fiber friction material and a preparation method thereof, comprising the following steps:

[0007] Step 1: Prepare the following raw materials by weight: 40-45 parts of carbon fiber composite recycled particles, 25-30 parts of bonding phenolic resin, 5-10 parts of wollastonite fiber, 10-15 parts of silicon powder, and 60-80 parts of ethanol;

[0008] The second step is to soak the first carbon fiber composite material recycled particles in a KH570 silane coupling agent aqueous solution with a concentration of 2.5-4.5g / mL, and dry them to obtain silane pretreated carbon fiber composite material recycled particles, and the second carbon fiber composite material recycled particles are carbonized and chemical vapor deposition treated, the carbonization temperature is 700-800°C, the carbonization time is 2-3h, the chemical vapor deposition temperature is 840-900°C, and the time is 2-4h, to obtain carbonization-chemical vapor deposition pretreated carbon fiber composite material recycled particles;

[0009] The third step is to mix and stir the silane pretreated carbon fiber composite material recycled particles, carbonization-chemical vapor deposition pretreated carbon fiber composite material recycled particles, bonding phenolic resin, silicon powder, ethanol and silica lime fiber at a stirring speed of 35-50r / min for 20-30min, and dry to obtain a prefabricated material;

[0010] The fourth step is to mold the prefabricated material, the first molding temperature is 80-90°C, the pressure is 10-12MPa, and the time is 30-45min; the second molding temperature is 100-120°C, the pressure is 14-16MPa, and the time is 60-80min; the third molding temperature is 160-180°C, the pressure is 20-30MPa, and the time is 180-240min to obtain a carbon fiber friction material.

[0011] Furthermore, the carbon fiber composite material recycled particles include first carbon fiber composite material recycled particles and second carbon fiber composite material recycled particles, the particle size of the first carbon fiber composite material recycled particles is 1-2 mm, and the particle size of the second carbon fiber composite material recycled particles is 3-4 mm.

[0012] Furthermore, the mass ratio of the first carbon fiber composite material recycled particles to the second carbon fiber composite material recycled particles is 1:1.

[0013] Furthermore, the average length of the wollastonite fibers is 180-210 μm.

[0014] Further, the bonding phenolic resin comprises the following steps:

[0015] S1. Add phenol, formaldehyde, cardanol and manganese sulfate into a flask and mix them, then add hydrochloric acid, react at room temperature for 2-4 hours, vacuum dry, and then add nitrile rubber powder to obtain nitrile rubber modified phenolic resin;

[0016] S2, adding 3-(2,3-epoxypropoxy)propyltrimethoxysilane and nitrile rubber modified phenolic resin into a flask, stirring at 75-85°C for 30-90min, then adding a catalyst, reacting for 6-9h, then heating to 95-120°C, and distilling under reduced pressure for 30-60min to obtain intermediate A;

[0017] S3, adding intermediate A, nitrile rubber modified phenolic resin, acetone and triethanolamine into a flask, mixing evenly, and drying in a vacuum oven at room temperature to obtain a bonding phenolic resin.

[0018] Furthermore, the mass ratio of phenol, formaldehyde, cardanol, manganese sulfate, hydrochloric acid and nitrile rubber is (56-64):(40-44):(12-18):(0.5-0.8):(0.5-0.8):(8-12).

[0019] Furthermore, the mass ratio of the 3-(2,3-epoxypropoxy)propyltrimethoxysilane, the nitrile rubber modified phenolic resin and the catalyst is 1:1-2:0.01-0.04.

[0020] Furthermore, the catalyst includes one or more of the following: glacial acetic acid, p-toluenesulfonic acid, triethylamine and sodium hydroxide.

[0021] Furthermore, the mass ratio of the intermediate A, the nitrile rubber modified phenolic resin and the triethanolamine is 1-1.6:1:0.01-0.02.

[0022] Beneficial effects of the present invention:

[0023] 1. The present invention provides a carbon fiber friction material and a preparation method thereof. Carbon fiber composite material recycled particles, bonding phenolic resin, wollastonite fiber, silicon powder, ethanol and other raw materials are mixed and stirred, dried to obtain a prefabricated material, and then molded to obtain a carbon fiber friction material. The obtained material has good friction resistance and can meet the needs of reducing wear and improving tensile properties.

[0024] 2. The present invention introduces siloxane groups into the nitrile rubber modified phenolic resin by chemical means, which, on the one hand, improves the thermal stability of the nitrile rubber while ensuring that the nitrile rubber modified phenolic resin maintains its original high oil resistance; on the other hand, the siloxane groups have excellent flexibility, and their introduction can improve the toughness of the nitrile rubber modified phenolic resin to a certain extent.

[0025] 3. The present invention uses chemical means to carry out curing reaction of intermediate A, nitrile rubber modified phenolic resin, acetone and triethanolamine, and cross-links through phenolic hydroxyl groups or alcoholic hydroxyl groups, triethanolamine and epoxy groups through hydrogen bonds, thereby enhancing the interfacial bonding strength between the resin matrix and the carbon fiber and introducing flexible long chains to improve the tensile properties of the material. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments 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] Example 1

[0028] A bonding phenolic resin is prepared by the following steps:

[0029] S1, add 28g phenol, 20g formaldehyde, 6g cardanol and 0.25g manganese sulfate into a flask, mix, then add 0.25g hydrochloric acid, react at 25°C for 2h, vacuum dry, and then add 4g nitrile rubber powder to obtain nitrile rubber modified phenolic resin;

[0030] S2, add 20g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 20g of nitrile rubber modified phenolic resin into a flask, stir at 75°C for 30min, then add 0.2g of glacial acetic acid, react for 6h, then heat to 95°C, and distill under reduced pressure for 30min to obtain intermediate A;

[0031] S3, add 10g intermediate A, 10g nitrile rubber modified phenolic resin, 200ml acetone solvent and 0.1g triethanolamine into a flask, mix well, place in a vacuum oven at 25°C and dry to obtain a bonding phenolic resin.

[0032] Example 2

[0033] A bonding phenolic resin is prepared by the following steps:

[0034] S1, add 32g phenol, 22g formaldehyde, 9g cardanol and 0.4g manganese sulfate into a flask, mix, then add 0.4g hydrochloric acid, react at 30°C for 4h, vacuum dry, and then add 6g nitrile rubber powder to obtain nitrile rubber modified phenolic resin;

[0035] S2, add 20g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 40g of nitrile rubber modified phenolic resin into a flask, stir at 85°C for 90min, then add 0.8g of glacial acetic acid, react for 9h, then heat to 120°C, and distill under reduced pressure for 60min to obtain intermediate A;

[0036] S3, add 16g intermediate A, 10g nitrile rubber modified phenolic resin, 200ml acetone solvent and 0.2g triethanolamine into a flask, mix well, place in a 30°C vacuum oven and dry to obtain a bonding phenolic resin.

[0037] Example 3

[0038] A bonding phenolic resin is prepared by the following steps:

[0039] S1, add 30g phenol, 21g formaldehyde, 8g cardanol and 0.3g manganese sulfate into a flask, mix, then add 0.3g hydrochloric acid, react at 28°C for 3h, vacuum dry, then add 5g nitrile rubber powder to obtain nitrile rubber modified phenolic resin;

[0040] S2, add 20g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 30g of nitrile rubber modified phenolic resin into a flask, stir at 80°C for 60min, then add 0.4g of glacial acetic acid, react for 8h, then heat to 100°C, and distill under reduced pressure for 40min to obtain intermediate A;

[0041] S3, add 12g intermediate A, 10g nitrile rubber modified phenolic resin, 200ml acetone solvent and 0.16g triethanolamine into a flask, mix well, place in a vacuum oven at 28°C and dry to obtain a bonding phenolic resin.

[0042] Example 4

[0043] A carbon fiber friction material and a preparation method thereof, comprising the following steps:

[0044] Step 1: prepare the following raw materials by weight: 20 parts of the first carbon fiber composite material recycled particles, 20 parts of the second carbon fiber composite material recycled particles, 25 parts of the bonding phenolic resin of Example 1, 5 parts of wollastonite fiber, 10 parts of silicon powder, and 60 parts of ethanol;

[0045] The second step is to soak the first carbon fiber composite material regenerated particles in a KH570 silane coupling agent aqueous solution with a concentration of 2.5g / mL, the particle size of the first carbon fiber composite material regenerated particles is 1mm, and dry to obtain silane pretreated carbon fiber composite material regenerated particles, and the second carbon fiber composite material regenerated particles are carbonized and chemical vapor deposition treated, the carbonization temperature is 700°C, the carbonization time is 2h, the chemical vapor deposition temperature is 840°C, the time is 2h, the particle size of the second carbon fiber composite material regenerated particles is 3mm, and carbonization-chemical vapor deposition pretreated carbon fiber composite material regenerated particles are obtained;

[0046] The third step is to mix and stir the silane pretreated carbon fiber composite material recycled particles, carbonization-chemical vapor deposition pretreated carbon fiber composite material recycled particles, bonding phenolic resin, silicon powder, ethanol and silica lime fiber, the stirring speed is 35r / min, the stirring time is 20min, the average length of the silica lime fiber is 180μm, and dry to obtain a prefabricated material;

[0047] The fourth step is to mold the prefabricated material. The first molding temperature is 80°C, the pressure is 10MPa, and the time is 30min; the second molding temperature is 100°C, the pressure is 14MPa, and the time is 60min; the third molding temperature is 160°C, the pressure is 20MPa, and the time is 180min to obtain a carbon fiber friction material.

[0048] Example 5

[0049] A carbon fiber friction material and a preparation method thereof, comprising the following steps:

[0050] Step 1: Prepare the following raw materials by weight: 22.5 parts of the first carbon fiber composite material recycled particles, 22.5 parts of the second carbon fiber composite material recycled particles, 30 parts of the bonding phenolic resin of Example 2, 10 parts of wollastonite fiber, 15 parts of silicon powder, and 80 parts of ethanol;

[0051] The second step is to soak the first carbon fiber composite material regenerated particles in a KH570 silane coupling agent aqueous solution with a concentration of 4.5 g / mL, and dry them to obtain silane pretreated carbon fiber composite material regenerated particles, and the second carbon fiber composite material regenerated particles are carbonized and chemical vapor deposition treated, the carbonization temperature is 800°C, the carbonization time is 3h, the chemical vapor deposition temperature is 900°C, and the time is 4h, to obtain carbonization-chemical vapor deposition pretreated carbon fiber composite material regenerated particles;

[0052] The third step is to mix and stir the silane pretreated carbon fiber composite material regenerated particles, carbonization-chemical vapor deposition pretreated carbon fiber composite material regenerated particles, bonding phenolic resin, silicon powder, ethanol and silica lime fiber, the stirring speed is 50r / min, the stirring time is 30min, the average length of the silica lime fiber is 210μm, and dry to obtain a prefabricated material;

[0053] The fourth step is to mold the prefabricated material. The first molding temperature is 90°C, the pressure is 12MPa, and the time is 45min; the second molding temperature is 120°C, the pressure is 16MPa, and the time is 80min; the third molding temperature is 180°C, the pressure is 30MPa, and the time is 240min to obtain a carbon fiber friction material.

[0054] Example 6

[0055] A carbon fiber friction material and a preparation method thereof, comprising the following steps:

[0056] Step 1: Prepare the following raw materials by weight: 21 parts of the first carbon fiber composite material recycled particles, 21 parts of the second carbon fiber composite material recycled particles, 26 parts of the bonding phenolic resin of Example 2, 8 parts of wollastonite fiber, 12 parts of silicon powder, and 70 parts of ethanol;

[0057] The second step is to soak the first carbon fiber composite material regenerated particles in a 3g / mL KH570 silane coupling agent aqueous solution, and dry them to obtain silane pretreated carbon fiber composite material regenerated particles, and the second carbon fiber composite material regenerated particles are carbonized and chemical vapor deposition treated, the carbonization temperature is 760°C, the carbonization time is 2.5h, the chemical vapor deposition temperature is 880°C, and the time is 3h, to obtain carbonization-chemical vapor deposition pretreated carbon fiber composite material regenerated particles;

[0058] The third step is to mix and stir the silane pretreated carbon fiber composite material recycled particles, carbonization-chemical vapor deposition pretreated carbon fiber composite material recycled particles, bonding phenolic resin, silicon powder, ethanol and silica lime fiber, the stirring speed is 40r / min, the time is 25min, the average length of the silica lime fiber is 200μm, and dry to obtain a prefabricated material;

[0059] The fourth step is to mold the prefabricated material. The first molding temperature is 85°C, the pressure is 11MPa, and the time is 40min; the second molding temperature is 110°C, the pressure is 15MPa, and the time is 70min; the third molding temperature is 170°C, the pressure is 25MPa, and the time is 200min to obtain a carbon fiber friction material.

[0060] Comparative Example 1

[0061] Compared with Example 5, the "bonding phenolic resin" in Example 5 is replaced by "boron-modified phenolic resin", and the remaining raw materials and preparation process are the same as Example 5.

[0062] The results of Examples 4 to 6 and Comparative Example 1 were tested, and the tensile properties of the materials were tested using a 3365 material tensile testing machine; the friction properties of the composite material were tested using a micro-nanomechanics comprehensive testing system (UNMT-1), and the load pressure was 10 N. The mass wear rate of the composite material was calculated using the formula w=Δm / (NTV), where Δm is the wear amount, the wear time T is 3h, and the wear velocity V is 5mm / s.

[0063] The test results are shown in Table 1:

[0064] Table 1

[0065] project Example 4 Example 5 Example 6 Comparative Example 1 Tensile properties (MPa) 86 98 92 78 Wear rate (%) 2.46 2.12 2.24 4.24

[0066] It can be seen from Table 1 that, compared with Comparative Example 1, the tensile properties obtained in Examples 4-6 are between 86 and 98, which shows that the carbon fiber friction materials prepared in the examples of the present invention have strong tensile properties, and the wear rates obtained in Examples 4-6 are between 2.12 and 2.46, which shows that the carbon fiber friction materials prepared in the examples of the present invention have good friction properties.

[0067] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0068] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a carbon fiber friction material, characterized in that: The following steps are involved: Step 1: Prepare the following raw materials by weight: 40-45 parts of carbon fiber composite recycled particles, 25-30 parts of bonding phenolic resin, 5-10 parts of wollastonite fiber, 10-15 parts of silicon powder, and 60-80 parts of ethanol; The second step is to soak the first carbon fiber composite material recycled particles in a KH570 silane coupling agent aqueous solution with a concentration of 2.5-4.5g / mL, and dry them to obtain silane pretreated carbon fiber composite material recycled particles, and the second carbon fiber composite material recycled particles are carbonized and chemical vapor deposition treated, the carbonization temperature is 700-800°C, the carbonization time is 2-3h, the chemical vapor deposition temperature is 840-900°C, and the time is 2-4h, to obtain carbonization-chemical vapor deposition pretreated carbon fiber composite material recycled particles; The third step is to mix and stir the silane pretreated carbon fiber composite material recycled particles, carbonization-chemical vapor deposition pretreated carbon fiber composite material recycled particles, silicon powder, bonding resin, ethanol and silica lime fiber at a stirring speed of 35-50r / min for 20-30min, and dry to obtain a prefabricated material; The fourth step is to mold the prefabricated material, the first molding temperature is 80-90°C, the pressure is 10-12MPa, and the time is 30-45min; the second molding temperature is 100-120°C, the pressure is 14-16MPa, and the time is 60-80min; the third molding temperature is 160-180°C, the pressure is 20-30MPa, and the time is 180-240min to obtain a carbon fiber friction material.

2. The method for preparing a carbon fiber friction material according to claim 1, characterized in that: The carbon fiber composite material recycled particles include first carbon fiber composite material recycled particles and second carbon fiber composite material recycled particles, the particle size of the first carbon fiber composite material recycled particles is 1-2mm, the particle size of the second carbon fiber composite material recycled particles is 3-4mm, and the mass ratio of the first carbon fiber composite material recycled particles to the second carbon fiber composite material recycled particles is 1-1.2:

1.

3. The method for preparing a carbon fiber friction material according to claim 1, characterized in that: The mass ratio of the first carbon fiber composite material recycled particles to the second carbon fiber composite material recycled particles is 1:

1.

4. The method for preparing a carbon fiber friction material according to claim 1, characterized in that: The average length of the wollastonite fibers is 180-210 μm.

5. The method for preparing a carbon fiber friction material according to claim 1, characterized in that: The bonding phenolic resin The method comprises the following steps: S1. Add phenol, formaldehyde, cardanol and manganese sulfate into a flask and mix them, then add hydrochloric acid, react at room temperature for 2-4 hours, vacuum dry, and then add nitrile rubber powder to obtain nitrile rubber modified phenolic resin; S2, adding 3-(2,3-epoxypropoxy)propyltrimethoxysilane and nitrile rubber modified phenolic resin into a flask, stirring at 75-85°C for 30-90min, then adding a catalyst, reacting for 6-9h, then heating to 95-120°C, and distilling under reduced pressure for 30-60min to obtain intermediate A; S3, adding intermediate A, nitrile rubber modified phenolic resin, acetone and triethanolamine into a flask, mixing evenly, and drying in a vacuum oven at room temperature to obtain a bonding phenolic resin.

6. The method for preparing a carbon fiber friction material according to claim 5, characterized in that: The mass ratio of the phenol, formaldehyde, cardanol, manganese sulfate, hydrochloric acid and nitrile rubber is (56-64):(40-44):(12-18):(0.5-0.8):(0.5-0.8):(8-12).

7. The method for preparing a carbon fiber friction material according to claim 5, characterized in that: The mass ratio of the 3-(2,3-epoxypropoxy)propyltrimethoxysilane, the nitrile rubber modified phenolic resin and the catalyst is 1:1-2:0.01-0.

04.

8. The method for preparing a carbon fiber friction material according to claim 5, characterized in that: The catalyst includes one or more of the following: glacial acetic acid, p-toluenesulfonic acid, triethylamine and sodium hydroxide.

9. The method for preparing a carbon fiber friction material according to claim 5, characterized in that: The mass ratio of the intermediate A, the nitrile rubber modified phenolic resin and the triethanolamine is 1-1.6:1:0.01-0.02.