Nanometer ceramic composite friction plate and preparation method and application thereof

Abstract

The invention discloses a nano ceramic composite friction plate and a preparation method and application thereof.The preparation method comprises the steps that sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metal and metal oxide filler are mixed and then stirred at a high speed, a premix is obtained, phenolic resin and rubber are added into the premix, then high-speed stirring is conducted, and the nano ceramic composite friction plate is obtained. A mixed ingredient is obtained; a preheated mold cavity is filled with the mixed ingredients for compression molding, and the friction plate is obtained; and carrying out heat treatment on the friction plate, and then carrying out cooling and polishing treatment to obtain the nano ceramic composite friction plate for the servo motor brake. Through nano-composite reinforcement, a multi-component synergistic effect and precise process control, the core performance of high strength, low abrasion and wide temperature range stability of the friction plate is achieved, and the requirements for high-load and long-period operation of motor equipment are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of friction materials, and particularly relates to a nano-ceramic composite friction plate, a preparation method thereof, and an application thereof. Background Art

[0002] With the improvement of the performance requirements for braking systems in fields such as new energy vehicles and intelligent equipment, friction materials are iteratively developing towards high heat resistance and low wear. The current technical system mainly includes three categories: semi-metallic sintered materials, organic resin-based composite materials, and copper-based powder metallurgy materials. Among them, semi-metallic materials enhance mechanical strength through steel fiber reinforcement, organic-based materials use aramid fibers to achieve vibration reduction and noise reduction, and copper-based materials use powder metallurgy technology to ensure thermal conductivity. In recent years, nano-ceramic composite technology has begun to be applied in the field of friction materials. Through the composite design of ceramic phases such as alumina and silicon carbide and non-metallic matrices, a new type of friction material system with a gradient structure has gradually been formed. These technological evolutions provide diversified solutions for the development of high-performance servo motor brakes.

[0003] In the current mainstream friction material system, in the case of continuous braking conditions, when the temperature is too high, the phenolic resin matrix in semi-metallic sintered materials begins to undergo pyrolysis carbonization reaction, resulting in a decrease in the friction coefficient. At the same time, the thermal mismatch between the reinforcing fiber and the resin matrix causes interfacial peeling, forming a microcrack network; in organic-based composite materials, when the braking temperature is too high, the resin thermally decomposes to generate pores, resulting in a reduction in the effective contact area and an increase in the wear rate; due to the hardness difference between copper powder and hard phases in copper-based powder metallurgy materials, periodic stress concentration is formed at the friction interface, leading to braking noise, and heavy metals such as lead and antimony in the material generate environmental pollutants during the braking wear process. These technical bottlenecks restrict the improvement of the reliability of the electric motor braking system under high-temperature and high-frequency conditions. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a nano-ceramic composite friction plate, a preparation method thereof, and an application thereof for solving the technical problems of low friction coefficient, unstable torque, serious thermal fade, and poor wear resistance, and improving the performance of the servo motor brake in view of the above-mentioned deficiencies in the prior art.

[0005] The present invention adopts the following technical solutions: A preparation method of a nano-ceramic composite friction plate, comprising the following steps: Mix sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals, and metal oxide fillers, and obtain a premix through high-speed stirring. Add phenolic resin and rubber to the premix, and then conduct high-speed stirring to obtain a mixed formulation; Fill the mixed formulation into a preheated mold cavity for compression molding to obtain a friction plate; The friction plate is heat-treated, and then after cooling and grinding treatments, a nano-ceramic composite friction plate for a servo motor brake is produced.

[0006] Preferably, the mass percentages of phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals and metal oxide fillers are as follows: Phenolic resin: 16% - 21%, rubber: 4% - 9%, sulfur: 0.1% - 0.5%, calcium silicate: 25% - 35%, aramid pulp: 4% - 10%, composite mineral fiber: 4% - 10%, magnesium oxide: 18% - 23%, zirconium silicate: 4% - 7%, iron disulfide: 1% - 5%, other metals and metal oxide fillers: 5% - 15%.

[0007] Preferably, the stirring time of the premix is 2 - 3 minutes, and the stirring speed is 20000 - 25000 revolutions per minute.

[0008] Preferably, the stirring time of the mixed ingredients is 1 - 2 minutes, and the stirring speed is 20000 - 25000 revolutions per minute.

[0009] Preferably, during the compression molding process, the exhaust number is controlled to be 6 - 8 times, the holding pressure is 25 - 35 MPa, and the temperature is 160 - 180 °C.

[0010] Preferably, the preheating temperature of the mold cavity is 160 - 180 °C, and the preheating time is 10 - 15 minutes.

[0011] Preferably, the temperature of the heat treatment is 160 - 180 °C, and the heat treatment time is 4 - 5 hours.

[0012] Another technical solution of the present invention is a nano-ceramic composite friction plate.

[0013] Preferably, the friction coefficient of the nano-ceramic composite friction plate is 0.65 - 0.75; the high-temperature torque attenuation at 100 °C is less than 20%, and the low-temperature torque attenuation at -30 °C is less than 5%; when the moment of inertia is 0.5 - 1 kg / m 3 , the motor speed is 400 - 600 revolutions per minute, and the braking life is greater than or equal to 500 times.

[0014] The third technical solution of the present invention is the application of the nano-ceramic composite friction plate in a servo motor brake.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: A preparation method of a nano-ceramic composite friction plate uses phenolic resin as a binder and nitrile rubber for toughening, enhancing the toughness and integrity of the friction plate; calcium silicate is used as a filler and reinforcing fiber, collaborating with various fillers such as zirconium silicate to enhance the strength and wear resistance of the friction plate and extend its service life; aramid pulp and composite mineral fiber are used as reinforcing materials to improve the fatigue resistance of the friction plate, making it not easily break under the action of cyclic stress and extending its service life; magnesium oxide can effectively improve the wear resistance and high-temperature resistance of the friction plate due to its high hardness and good high-temperature performance; sulfur vulcanization is used to optimize the internal structure. Other metal fillers improve the friction performance, ensure the stability of the friction coefficient, and adapt to complex working conditions; iron disulfide has a layered crystal structure with weak interlayer bonding force, and these layered structures are prone to sliding during the friction process to form a lubricating film, thereby reducing the direct contact between the friction pairs and reducing wear; the high surface area and active surface energy of micro-nano scale particle fillers enable them to be evenly distributed in the matrix to form a stable friction interface, which can avoid stress concentration, promote uniform wear, and reduce secondary wear caused by abrasive particle shedding.

[0016] Furthermore, a phenolic resin ratio of 16% - 21% can not only ensure the overall bonding strength of the material but also avoid the increase in brittleness of the friction plate caused by excessive resin, collaborating with the rubber to form a "resin-elastomer composite matrix" to balance rigidity and toughness; a rubber ratio of 4% - 9% and a sulfur ratio of 0.1% - 0.5% avoid excessive reduction in material hardness, improve the heat resistance of the elastomer, and inhibit the high-temperature softening of the rubber; a calcium silicate ratio of 23% - 35% reduces the material density and production cost, and at the same time improves the wear resistance as a hard filler; the aramid pulp accounts for 4% - 10%, using its high specific surface area to enhance the interfacial bonding force between the resin and the filler and inhibit material delamination; the composite mineral fiber accounts for 4% - 10%, directionally enhancing the high-temperature strength and compensating for the decrease in resin high-temperature strength; 18% - 23% of magnesium oxide is used to absorb the acidic gas generated by the decomposition of the resin during braking to prevent corrosion of the brake disc; zirconium silicate has high hardness, and a ratio of 4% - 7% can directionally improve the wear resistance of the material while avoiding excessive wear of the brake disc caused by overdosage; 1% - 5% of iron disulfide, with a low ratio, can form a continuous lubricating film at the friction interface to reduce the difference between the static and dynamic friction coefficients; 5% - 15% of other metals and metal oxide fillers, such as copper powder, can improve the thermal conductivity, and alumina can enhance the wear resistance, etc.

[0017] Furthermore, high-speed stirring of the premix (20000 - 25000 revolutions per minute) generates strong shear force, instantaneously dispersing the easily agglomerated light fillers and high-density metal powders to avoid local compositional segregation. Aramid pulp and mineral fibers are prone to breakage under long-term high-speed stirring, and short-time operation (2 - 3 minutes) maintains the fiber aspect ratio to ensure the anti-delamination ability of the friction plate.

[0018] Furthermore, phenolic resin and rubber may undergo pre-curing or premature vulcanization under high-speed frictional heat generation. Short-term stirring for 1 - 2 minutes can control the temperature rise below 80°C.

[0019] Furthermore, when phenolic resin cures, small molecules such as water vapor and formaldehyde are released, and trace amounts of sulfide gases are generated during the rubber vulcanization process. Exhausting 6 - 8 times can prevent gas accumulation from forming internal pores; the holding pressure is 25 - 35 MPa. When the pressure is lower than 25 MPa, the bonding between filler particles is insufficient, and when it is higher than 35 MPa, it may cause fiber fracture.

[0020] Furthermore, the heat treatment temperature is 160 - 180°C, and the time is 4 - 5 hours. 160°C is the upper threshold above the glass transition temperature of the resin, triggering the cross-linking reaction; the 180°C upper limit prevents excessive curing of the resin. The peak vulcanization activity of nitrile rubber is at 165°C, overlapping with the resin curing temperature window, achieving synchronous cross-linking and avoiding interface delamination. After pressing and forming, there are non-uniform stresses inside the material. Slow heat treatment for more than 4 hours relaxes the molecular chains and releases the stresses; aramid fibers will undergo hydrolysis degradation when exposed at 180°C for more than 5 hours, and the 5-hour upper limit protects the fiber integrity.

[0021] In summary, the nano-ceramic composite friction plate prepared by the present invention has the advantages of high and stable friction coefficient, stable high and low temperature performance, small wear rate, long service life, etc. This friction plate can effectively solve the deficiencies of existing friction plates in terms of friction coefficient, wear resistance, etc., improve the performance and reliability of the servo motor brake, and ensure the safe and stable operation of the servo motor.

[0022] The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings to be used in the following description of the embodiments will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is the surface morphology analysis diagram of the scanning electron microscope of Embodiment 1 of the present invention. Among them, (a) is the scanning electron microscope photo of the friction plate of Embodiment 1 at 38 times, (b) is the scanning electron microscope photo of the friction plate of Embodiment 1 at 38 times, (c) is the scanning electron microscope photo of the friction plate of Embodiment 1 at 1000 times, and (d) is the scanning electron microscope photo of the friction plate of Embodiment 1 at 1000 times; Figure 2 It is the friction coefficient test result diagram of Embodiment 1 of the present invention; Figure 3This is the graph of the life test results for Embodiment 1 of the present invention. Detailed implementation manners

[0025] The technical solutions of the present invention will be described clearly and completely below. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0026] In the present invention, if there is no special indication, all the implementation manners and preferred implementation methods mentioned herein can be combined with each other to form a new technical solution.

[0027] In the present invention, if there is no special indication, all the technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0028] In the present invention, if there is no special indication, the percentage (%) or part refers to the weight percentage or weight part relative to the composition.

[0029] In the present invention, if there is no special indication, the various components or their preferred components involved can be combined with each other to form a new technical solution.

[0030] In the present invention, unless otherwise stated, the numerical range "a to b" represents the abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "16 to 21" means that all real numbers between "16 to 21" have been fully listed herein, and "16 to 21" is only the abbreviated representation of these numerical combinations.

[0031] The "range" disclosed in the present invention can be in the form of one or more lower limits and one or more upper limits, respectively.

[0032] In the present invention, the term "and / or" used herein refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0033] In the present invention, unless otherwise stated, each reaction or operation step can be carried out sequentially or in sequence. Preferably, the reaction methods herein are carried out sequentially.

[0034] Unless otherwise stated, the professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any method or material similar or equivalent to the described content can also be applied to the present invention.

[0035] The present invention provides a nano-ceramic composite friction plate, its preparation method and application. A nano-composite structure design is adopted, and the specific process is as follows: First, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals and metal oxide fillers are pre-mixed, and then secondary stirring is carried out with phenolic resin and rubber to obtain a uniform mixture. Subsequently, the mold is preheated at 160 °C, and then compression molding is carried out by a flat vulcanizing machine. Manual exhaust is used to ensure the density of the material, and demolding is carried out after pressure holding. Finally, internal stress is eliminated through gradient heat treatment, and the finished product is obtained by fine grinding; A composite matrix of phenolic resin and rubber is adopted, combined with a zirconium silicate / metal oxide filler system to form a nano-enhanced network, making the product have both high hardness and impact resistance; Through the synergistic effect of magnesium oxide and calcium silicate, a stable friction coefficient is maintained in the range of -30~100 °C to adapt to extreme working conditions; The staged mixing process avoids pre-curing of the resin, and the stepped hot pressing molding combined with the post-treatment process makes the porosity less than 2%, the hardness reaches HRC58-62, and the wear rate is reduced by more than 40% compared with traditional products. It is especially suitable for the long-term braking requirements under the conditions of frequent start and stop of motor equipment and high load working conditions.

[0036] A preparation method of a nano-ceramic composite friction plate according to the present invention includes the following steps: S1. Take appropriate amounts of phenolic resin, rubber, sulfur, calcium silicate, magnesium oxide, zirconium silicate, other metals and metal oxide fillers for standby; Phenolic resin: 16% - 21%, rubber 4% - 9%, sulfur 0.1% - 0.5%, calcium silicate 25% - 35%, aramid pulp 4% - 10%, composite mineral fiber 4% - 10%, magnesium oxide 18% - 23%, zirconium silicate 4% - 7%, iron disulfide 1% - 5%, other metals and metal oxide fillers 5% - 15%.

[0037] Preferably, the phenolic resin is a cashew shell oil modified phenolic resin powder, which can improve the thermal performance of the phenolic resin, enhance the stability of the friction plate under high-temperature working conditions, reduce the phenomenon of thermal fade, and avoid a significant decrease in braking efficiency due to high temperature.

[0038] Preferably, the rubber is nitrile rubber powder. Nitrile rubber has good oil resistance, can effectively resist the erosion of oily substances such as lubricating oil in servo motors, maintain the stable performance of the friction plate, and extend its service life.

[0039] Preferably, the calcium silicate is acicular wollastonite powder. Its acicular structure enables it to play a reinforcing role in the friction plate like a fiber, effectively improving the strength and hardness of the friction plate, enhancing its ability to resist wear and deformation during the friction process, and extending its service life.

[0040] Preferably, the lengths of both the aramid pulp and the composite mineral fiber are 1 to 3 mm. The shorter fiber length is beneficial to improving the dispersibility of the aramid pulp and the composite mineral fiber and promoting uniform mixing of the mixture.

[0041] Preferably, the magnesium oxide is nano-magnesium oxide powder.

[0042] Preferably, the zirconium silicate is nano-zirconium silicate.

[0043] Preferably, the iron disulfide is nano-iron disulfide.

[0044] Preferably, other metal and non-metal oxide fillers are all micro-nano scale powders.

[0045] S2. Add the sulfur, calcium silicate, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken out in step S1 into a high-speed mixer, control the rotation speed at 20,000 to 25,000 revolutions per minute, and stir for 2 to 3 minutes to obtain a premix. S3. Add the phenolic resin and rubber taken out in step S1 and the premix obtained in step S2 into a high-speed mixer together, control the rotation speed at 20,000 to 25,000 revolutions per minute, and stir for 1 to 2 minutes to obtain a mixed blend. S4. Place the mold on the heating plate of a flat vulcanizing machine, set the temperature at 160 to 180 °C, and preheat for 10 to 15 minutes. S5. Fill the mixed blend obtained in step S2 into the preheated mold cavity in step S4. S6. Manually adjust the flat vulcanizing machine to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air. After the air exhaust is complete, enter the pressure-holding state. Among them, the number of air exhausts of the flat vulcanizing machine is 6 to 8 times, the pressure-holding pressure is 25 to 35 MPa, and the temperature is 160 to 180 °C.

[0046] S7. Open the mold of the hot-pressed mold in step S6 and eject the product from the mold. S8. Place the friction plate obtained in step S7 into an electric oven for heat treatment. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed sheet. Preferably, the heat treatment temperature of the electric oven is set at 160 to 180 °C, and the heat treatment time is 4 to 5 hours.

[0047] S9. Cool and polish the heat-treated friction plate, and polish each dimension to within the tolerance range required by the product to obtain the finished friction plate.

[0048] A nano-ceramic composite friction plate is prepared by the above method, with the friction coefficient stable between 0.65 and 0.75, the high-temperature torque attenuation at 100 °C being less than 20%, and the low-temperature torque attenuation at -30 °C being less than 5%. When the moment of inertia is 0.5 - 1 kg / m 3 , the motor speed is 400 - 600 revolutions per minute, and the braking life is greater than or equal to 500 times.

[0049] The nano-ceramic composite friction plate prepared by the method of the present invention can be applied in a servo motor brake.

[0050] Preferably, the nano-ceramic composite friction plate prepared by the present invention is suitable for application in the brakes of wind power pitch and yaw systems.

[0051] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Generally, the components described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] Example 1 The nano-ceramic composite friction plate formula provided in this example is as follows: Phenolic resin 17%, rubber 6.5%, sulfur 0.2%, calcium silicate 31%, aramid pulp 6%, composite mineral fiber 6%, magnesium oxide 20%, zirconium silicate 4.3%, iron disulfide 3%, other metal and metal oxide fillers 6%.

[0053] The manufacturing method of the nano-ceramic composite friction plate provided in this example is as follows: S1. Take the above percentages of phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers for standby; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken out in step S1 into a high-speed mixer, with a rotation speed of 25,000 revolutions per minute, and stir for 2 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken out in step S1 and the premix obtained in step S2 into a high-speed mixer together, with a rotation speed of 25,000 revolutions per minute, and stir for 1 minute to obtain a mixed ingredient; S4. Place the mold on the heating plate of the flat vulcanizing machine, set the temperature to 170 °C, and preheat for 10 minutes; S5. Fill the mixed ingredients obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizing machine to close the upper and lower molds for compression molding; during the pressing process, manually adjust the upper and lower molds to exhaust air, and enter the pressure-holding state after the air is completely exhausted; Among them, the number of exhausts of the flat vulcanizing machine is 7 times, the pressure-holding pressure is 25 MPa, and the temperature is 160 °C.

[0054] S7. Open the mold of the hot-pressed mold in step S6, and eject the product from the mold; S8. Put the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 4.5 hours, the temperature is 170 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed sheet; S9. Cool and polish the heat-treated friction plate, polish each dimension to within the tolerance range required by the product, and obtain a finished friction plate with a friction coefficient of 0.65.

[0055] Example 2 The nano-ceramic composite friction plate formula provided in this example is: Phenolic resin 16%, rubber 4%, sulfur 0.1%, calcium silicate 35%, aramid pulp 4%, composite mineral fiber 10%, magnesium oxide 18%, zirconium silicate 4%, iron disulfide 1%, other metal and metal oxide fillers 7.9%.

[0056] The manufacturing method of the nano-ceramic composite friction plate provided in this example is: S1. Take the phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers in the above percentages for standby; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken in step S1 into a high-speed mixer, with a rotation speed of 20,000 revolutions per minute, and stir for 3 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken in step S1 and the premix obtained in step S2 into a high-speed mixer together, with a rotation speed of 20,000 revolutions per minute, and stir for 2 minutes to obtain a mixed ingredient; S4. Place the mold on the heating plate of the flat vulcanizing machine, set the temperature to 160 °C, and preheat for 15 minutes; S5. Fill the mixed ingredients obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizer to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air. After complete exhaust, enter the pressure-holding state; Among them, the number of exhausts of the flat vulcanizer is 6 times, the pressure-holding pressure is 35 MPa, and the temperature is 180 °C; S7. Open the mold of the hot-pressed mold in step S6 and eject the product from the mold; S8. Put the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 4 hours, the temperature is 180 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed sheet; S9. Cool and polish the heat-treated friction plate, polish each dimension to within the tolerance range required by the product, and obtain a finished friction plate with a friction coefficient of 0.66.

[0057] Example 3 The nano-ceramic composite friction plate formula provided in this example is: Phenolic resin 21%, rubber 9%, sulfur 0.5%, calcium silicate 25%, aramid pulp 10%, composite mineral fiber 4%, magnesium oxide 18%, zirconium silicate 4%, iron disulfide 1%, other metal and metal oxide fillers 7.5%.

[0058] The manufacturing method of the nano-ceramic composite friction plate provided in this example is: S1. Take the phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers in the above percentages for standby; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken out in step S1 to a high-speed mixer, with a rotation speed of 20,000 revolutions per minute, and stir for 3 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken out in step S1 and the premix obtained in step S2 to a high-speed mixer together, with a rotation speed of 20,000 revolutions per minute, and stir for 2 minutes to obtain a mixed ingredient; S4. Place the mold on the heating plate of the flat vulcanizer, set the temperature to 180 °C, and preheat for 10 minutes; S5. Fill the mixed ingredient obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizer to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air. After complete exhaust, enter the pressure-holding state; Among them, the number of exhausts of the flat vulcanizer is 8 times, the pressure-holding pressure is 30 MPa, and the temperature is 170 °C; S7. Open the mold for the hot pressing in step S6 and eject the product from the mold; S8. Put the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 5 hours and the temperature is 170 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed piece; S9. Cool and polish the friction plate after heat treatment, and polish each dimension to within the tolerance range required by the product to obtain a finished friction plate with a friction coefficient of 0.68.

[0059] Example 4 The nano-ceramic composite friction plate provided in this example has the following formula: Phenolic resin 16%, rubber 4%, sulfur 0.2%, calcium silicate 31.8%, aramid pulp 4%, composite mineral fiber 4%, magnesium oxide 23%, zirconium silicate 7%, iron disulfide 5%, other metal and metal oxide fillers 5%.

[0060] The manufacturing method of the nano-ceramic composite friction plate provided in this example is as follows: S1. Take the phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers in the above percentages for standby; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken out in step S1 into a high-speed mixer, with a rotation speed of 25,000 revolutions per minute, and stir for 2 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken out in step S1 and the premix obtained in step S2 into a high-speed mixer together, with a rotation speed of 25,000 revolutions per minute, and stir for 1 minute to obtain a mixed ingredient; S4. Place the mold on the heating plate of a flat vulcanizer, set the temperature to 160 °C, and preheat for 15 minutes; S5. Fill the mixed ingredient obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizer to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air. After the air exhaust is complete, enter the pressure-holding state; Among them, the number of air exhausts of the flat vulcanizer is 8 times, the pressure-holding pressure is 30 MPa, and the temperature is 170 °C; S7. Open the mold for the hot pressing in step S6 and eject the product from the mold; S8. Put the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 4 hours and the temperature is 170 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed piece; S9. Cool and grind the friction plates after heat treatment, grind each dimension to within the tolerance range required by the product, and obtain finished friction plates with a friction coefficient of 0.70.

[0061] Example 5 The nano-ceramic composite friction plate formula provided in this example is as follows: Phenolic resin 18%, rubber 7%, sulfur 0.3%, calcium silicate 27%, aramid pulp 8%, composite mineral fiber 5%, magnesium oxide 20%, zirconium silicate 4%, iron disulfide 1%, other metal and metal oxide fillers 9.7%.

[0062] The manufacturing method of the nano-ceramic composite friction plate provided in this example is as follows: S1. Take the phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers in the above percentages for standby; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken in step S1 into a high-speed mixer, with a rotation speed of 23,000 revolutions per minute, and stir for 2.5 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken in step S1 and the premix obtained in step S2 into a high-speed mixer together, with a rotation speed of 23,000 revolutions per minute, and stir for 1.5 minutes to obtain a mixed formulation; S4. Place the mold on the heating plate of a flat vulcanizing machine, set the temperature to 165 °C, and preheat for 12 minutes; S5. Fill the mixed formulation obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizing machine to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air, and enter the pressure-holding state after the air exhaust is complete; Among them, the number of air exhausts of the flat vulcanizing machine is 8 times, the pressure-holding pressure is 28 MPa, and the temperature is 165 °C.

[0063] S7. Open the mold of the hot-pressed mold in step S6, and eject the product from the mold; S8. Place the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 5 hours, the temperature is 175 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed sheet; S9. Cool and grind the friction plates after heat treatment, grind each dimension to within the tolerance range required by the product, and obtain finished friction plates with a friction coefficient of 0.72.

[0064] Example 6 The nano-ceramic composite friction plate provided in this embodiment has the following formula: Phenolic resin 17%, rubber 4%, sulfur 0.4%, calcium silicate 30%, aramid pulp 4.6%, composite mineral fiber 5%, magnesium oxide 18%, zirconium silicate 4%, iron disulfide 2%, other metal and metal oxide fillers 15%.

[0065] The manufacturing method of the nano-ceramic composite friction plate provided in this embodiment is as follows: S1. Take the phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers in the above percentages for standby; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, and other metal and metal oxide fillers taken in step S1 into a high-speed mixer, with a rotation speed of 21,000 revolutions per minute, and stir for 2 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken in step S1 and the premix obtained in step S2 into a high-speed mixer together, with a rotation speed of 24,000 revolutions per minute, and stir for 1.5 minutes to obtain a mixed ingredient; S4. Place the mold on the heating plate of a flat vulcanizing machine, set the temperature to 175 °C, and preheat for 14 minutes; S5. Fill the mixed ingredient obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizing machine to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air. After the air exhaust is complete, enter the pressure-holding state; Among them, the number of air exhausts of the flat vulcanizing machine is 8 times, the pressure-holding pressure is 33 MPa, and the temperature is 170 °C.

[0066] S7. Open the mold of the hot-pressed mold in step S6, and eject the product from the mold; S8. Put the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 5 hours, the temperature is 175 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed piece; S9. Cool and polish the heat-treated friction plate, and polish each dimension to within the tolerance range required by the product to obtain a finished friction plate with a friction coefficient of 0.74.

[0067] Example 7 The nano-ceramic composite friction plate provided in this embodiment has the following formula: Phenolic resin 18%, rubber 7%, sulfur 0.3%, calcium silicate 27%, aramid pulp 8%, composite mineral fiber 5%, magnesium oxide 20%, zirconium silicate 4%, iron disulfide 1%, other metal and metal oxide fillers 9.7%.

[0068] The manufacturing method of the nano-ceramic composite friction plate provided by this embodiment is as follows: S1. Prepare phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals and metal oxide fillers in the above percentages; S2. Add the sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals and metal oxide fillers taken out in step S1 into a high-speed mixer, with a rotation speed of 24,000 revolutions per minute, and stir for 3 minutes to obtain a premix; S3. Add the phenolic resin and rubber taken out in step S1 and the premix obtained in step S2 into a high-speed mixer together, with a rotation speed of 23,000 revolutions per minute, and stir for 1 minute to obtain a mixed formulation; S4. Place the mold on the heating plate of a flat vulcanizing machine, set the temperature to 165 °C, and preheat for 11 minutes; S5. Fill the mixed formulation obtained in step S2 into the preheated mold cavity in step S4; S6. Manually adjust the flat vulcanizing machine to close the upper and lower molds for compression molding. During the pressing process, manually adjust the upper and lower molds to exhaust air, and enter the pressure-holding state after the air exhaust is complete; Among them, the number of air exhausts of the flat vulcanizing machine is 8 times, the pressure-holding pressure is 32 MPa, and the temperature is 165 °C.

[0069] S7. Open the mold of the hot-pressed mold in step S6, and eject the product from the mold; S8. Put the friction plate obtained in step S7 into an electric oven for heat treatment. The heat treatment time is 5 hours, the temperature is 175 °C. After the heat treatment is completed, cool it and check whether there are cracks or bubbles on the surface of the formed sheet; S9. Cool and polish the heat-treated friction plate, and polish each dimension to within the tolerance range required by the product to obtain a finished friction plate with a friction coefficient of 0.75.

[0070] Please refer to Figure 1 , and use a scanning electron microscope to analyze its surface morphology. Through observation with a scanning electron microscope, it can be clearly seen that the microstructure on the surface of the friction plate prepared in Example 1 is continuous, uniform and has a high density. This structure helps to improve the wear resistance and fatigue resistance of the material. The high-density surface can better withstand the shear force and compressive force during the friction process, reduce the generation and expansion of surface cracks, thereby improving the life and stability of the friction material.

[0071] Secondly, there are appropriate amounts of tiny voids on the surface of Example 1, which can play a role in enhancing the friction coefficient and heat dissipation: increasing the surface roughness to improve the friction coefficient; reducing heat accumulation during friction and preventing the material from failing due to overheating; Thirdly, it can be clearly observed that there is a columnar fiber structure in Example 1. As a reinforcing material, the fibers can well transfer the load, disperse the stress, prevent the collective from cracking, and enhance the fatigue resistance.

[0072] Thus, it can be seen that Example 1 has a reasonable surface density, void design, and fiber structure, which can effectively enhance the friction coefficient, wear resistance, fatigue resistance, and friction stability of the material.

[0073] Next, a friction performance comparison test is carried out on the friction plate prepared in Example 1 and the commercially available friction plate: 1. Friction coefficient test: Using a BRUKER-UMT friction and wear testing machine, the friction coefficient test is carried out on the friction plate of Example 1 and the commercially available friction plate under the same conditions.

[0074] The test conditions are as follows: Counterface: GCr15 steel ball; Pressure: 1 N; Reciprocating distance: 5 mm; Travel speed: 3 mm / s; Test duration: 1 h.

[0075] The test results of the friction coefficient are as Figure 2 shown. The results show that the friction coefficient of the friction plate in Example 1 is high and stable, while that of the commercially available friction plate is high but unstable. A higher friction coefficient can significantly enhance the braking torque of the brake, reduce the braking duration, and improve the braking effect; a stable friction coefficient can provide a stable torque for the brake and enhance the braking safety.

[0076] 2. High and low temperature tolerance test: Install the friction plates prepared in Example 1 and the commercially available friction plates on the servo motor brake, and put them into a thermostatic and humidistatic test chamber. The torque of the brake is tested at room temperature, -30 °C, and 100 °C respectively, and its attenuation rate is calculated.

[0077] The torque test method is as follows: when the brake is in the braking state, use a slow and uniform force to turn the torque wrench, turn it forward 10 times and backward 10 times, and the test results are averaged. The test results are shown in Table 1.

[0078]

[0079] The results show that the torque attenuation rate of the brake equipped with the friction plate of Example 1 is 3.96% at -30°C and 15.84% at 100°C; the torque attenuation rate of the brake equipped with the commercially available friction plate is 10.10% at -30°C and 47.47% at 100°C. Better high and low temperature tolerance can reduce the risk of brake failure in extreme environments, improve braking safety, and extend the service life of the brake.

[0080] 3. Life test: Install the friction plate prepared in Example 1 and the commercially available friction plate on the servo motor brake, install it on the motor, and perform simulated braking.

[0081] Test conditions: The moment of inertia is 1 kg / m 3 , motor speed: 600 revolutions per minute; The test results are as Figure 3 shown. The results show that the braking life of the brake equipped with the friction plate of Example 1 is more than 500 times; the braking life of the brake equipped with the commercially available friction plate is 240 times. (The rated torque of the brake is 80 Nm, and the torque lower than this value is regarded as the failure of the brake. The commercially available friction plate drags the brake during the 350 wear resistance tests, and the test is terminated one by one.) Better wear resistance can increase the number of braking times, extend the service life of the brake, reduce the risk of drag braking, reduce the maintenance cost of the brake, and thus improve economic benefits.

[0082] In summary, for a nano-ceramic composite friction plate, its preparation method and application of the present invention, through nano-composite reinforcement, multi-component synergistic effect and precise process control, realize the core properties of high strength, low wear and stable wide temperature range of the friction plate, and meet the high load and long cycle operation requirements of motor equipment.

[0083] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a nano-ceramic composite friction plate, characterized in that: The following steps are involved: Sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals and metal oxide fillers are mixed and stirred at high speed to obtain a premix, phenolic resin and rubber are added to the premix, and then stirred at high speed to obtain a mixed batch; Filling the mixed ingredients into a preheated mold cavity for compression molding to obtain a friction plate; The friction plate is subjected to heat treatment, cooling and grinding to obtain a nano-ceramic composite friction plate.

2. The method for preparing a nano-ceramic composite friction plate according to claim 1, characterized in that: The mass percentages of phenolic resin, rubber, sulfur, calcium silicate, aramid pulp, composite mineral fiber, magnesium oxide, zirconium silicate, iron disulfide, other metals and metal oxide fillers are as follows: Phenolic resin 16%~21%, rubber 4%~9%, sulfur 0.1%~0.5%, calcium silicate 25%~35%, aramid pulp 4%~10%, composite mineral fiber 4%~10%, magnesium oxide 18%~23%, zirconium silicate 4%~7%, iron disulfide 1%~5%, other metals and metal oxide fillers 5%~15%.

3. The method for preparing a nano-ceramic composite friction plate according to claim 1, characterized in that: The stirring time of the premix is ​​2 to 3 minutes, and the stirring speed is 20,000 to 25,000 rpm.

4. The method for preparing a nano-ceramic composite friction plate according to claim 1, characterized in that: The mixing time of the mixed ingredients is 1 to 2 minutes, and the mixing speed is 20,000 to 25,000 rpm.

5. The method for preparing a nano-ceramic composite friction plate according to claim 1, characterized in that: During the pressing process, the exhaust times are controlled to be 6 to 8 times, the holding pressure is 25 to 35 MPa, and the temperature is 160 to 180 degrees Celsius.

6. The method for preparing a nano-ceramic composite friction plate according to claim 5, characterized in that: The preheating temperature of the mold cavity is 160~180 degrees Celsius, and the preheating time is 10~15 minutes.

7. The method for preparing a nano-ceramic composite friction plate according to claim 1, characterized in that: The heat treatment temperature is 160~180 degrees Celsius, and the heat treatment time is 4~5 hours.

8. A nano-ceramic composite friction plate prepared according to the method according to any one of claims 1 to 7.

9. The nano-ceramic composite friction plate according to claim 8, characterized in that: The friction coefficient of the nano-ceramic composite friction plate is 0.65~0.75; the high temperature torque attenuation at 100 degrees Celsius is less than 20%, and the low temperature torque attenuation at minus 30 degrees Celsius is less than 5%; when the moment of inertia is 0.5~1kg / m 3 When the motor speed is 400~600 rpm, the braking life is greater than or equal to 500 times.

10. Use of the nano-ceramic composite friction plate according to claim 9 in a servo motor brake.

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