Brake disc and preparation method thereof, brake and vehicle

Abstract

The invention provides a brake disc and a preparation method thereof, a brake and a vehicle, and relates to the technical field of vehicle parts, and the brake disc comprises a structural layer and a friction layer arranged on at least one side of the structural layer; the structural layer and the friction layer meet the following conditions:-2H alpha m < = delta alpha < = 2H alpha m; wherein delta alpha = alpha m-alpha f, alpha m represents the thermal expansion coefficient of the structural layer, and alpha f represents the thermal expansion coefficient of the friction layer; h = H2 / H1, H1 represents the thickness of the structural layer, and H2 represents the thickness of the friction layer. By comprehensively considering the thicknesses and the thermal expansion coefficients of the structural layer and the friction layer, the thermal mismatch amount of the structural layer and the friction layer can be controlled within a proper range, thermal mismatch between the structural layer and the friction layer is reduced, the combination tightness of the structural layer and the friction layer is improved, and the service life of the friction layer is prolonged. The residual stress at the bonding interface of the structural layer and the friction layer in the braking process is reduced, and the performance stability of the brake disc is guaranteed.

Description

Technical Field

[0001] This application relates to the field of vehicle component technology, and in particular to a brake disc and its manufacturing method, a brake and a vehicle. Background Technology

[0002] Currently, aluminum-ceramic brake discs mainly consist of a friction layer and a structural layer. The structural layer typically uses aluminum alloy or aluminum alloy reinforced with a low volume fraction of ceramic particles, while the friction layer primarily uses aluminum alloy reinforced with a high volume fraction of ceramic particles. In related technologies, to meet the wear resistance requirements of the friction layer, the ceramic particle content can reach over 75%, or even be a pure ceramic layer. During the brake disc manufacturing process, if the thermal expansion coefficients of the structural layer and the friction layer differ significantly, thermal mismatch can easily occur between them, leading to cracking of the friction layer, or thermal fatigue during braking, resulting in serious problems such as brake failure. Summary of the Invention

[0003] This application provides a brake disc and its manufacturing method, a brake and a vehicle, which can improve the bonding strength between the structural layer and the friction layer and ensure the overall performance of the brake disc.

[0004] To achieve the above objectives, according to a first aspect of this application, a brake disc is provided, including a structural layer and a friction layer disposed on at least one side of the structural layer;

[0005] The structural layer and the friction layer satisfy: -2Hα m ≤Δα≤2Hα m ;

[0006] Where, Δα=α m -α f α m α represents the coefficient of thermal expansion of the structural layer. f H represents the coefficient of thermal expansion of the friction layer; H = H2 / H1, where H1 represents the thickness of the structural layer and H2 represents the thickness of the friction layer.

[0007] Optionally, 0.025 ≤ H2 / H1 ≤ 0.25.

[0008] Optionally, the raw materials of the structural layer include aluminum alloy material and a first ceramic material, wherein the volume ratio of the first ceramic material in the structural layer is V1, 0 < V1 ≤ 50%;

[0009] And / or, the raw material of the friction layer includes a second ceramic material, wherein the volume percentage of the second ceramic material in the friction layer is V2, 40% ≤ V2 ≤ 100%.

[0010] Optionally, the friction layer also includes aluminum alloy material and a third ceramic material, wherein the volume percentage of the third ceramic material in the friction layer is V3, and 40% ≤ V2 + V3 ≤ 100%.

[0011] Optionally, the first ceramic material includes silicon carbide, and the second ceramic material includes silicon carbide;

[0012] The coefficient of thermal expansion of the third ceramic material is greater than that of the second ceramic material.

[0013] Optionally, the coefficient of thermal expansion of the second ceramic material is C1, and the coefficient of thermal expansion of the third ceramic material is C2, wherein 2.3 × 10⁻⁶ -6 / ℃≤C2-C1≤10×10 -6 / ℃.

[0014] Optionally, the structural layer and the friction layer satisfy the following:

[0015] Where 'a' represents the coefficient of thermal expansion of the third ceramic material.

[0016] Optionally, the thickness H1 of the structural layer satisfies: 15mm≤H1≤60mm;

[0017] And / or, the thickness H2 of the friction layer satisfies: 0.5mm≤H2≤15mm.

[0018] Optionally, the thickness H1 of the structural layer satisfies: 20mm≤H1≤40mm;

[0019] And / or, the thickness H2 of the friction layer satisfies: 2mm≤H2≤10mm.

[0020] Optionally, the aluminum alloy material includes at least one of the two series aluminum alloy materials and the six series aluminum alloy materials;

[0021] And / or, the particle size of the aluminum alloy material is 5μm-20μm.

[0022] Optionally, the third ceramic material includes at least one of alumina, zirconium oxide, titanium carbide, and tungsten carbide.

[0023] Optionally, the particle size of the first ceramic material is 50μm-300μm;

[0024] And / or, the particle size of the second ceramic material is 50μm-300μm;

[0025] And / or, the particle size of the third ceramic material is 50μm-300μm.

[0026] Optionally, the friction layer includes a first friction layer and a second friction layer, which are respectively disposed on opposite sides of the structural layer;

[0027] The thickness of the friction layer is the total thickness of the first friction layer and the second friction layer.

[0028] Optionally, the coefficient of friction of the brake disc is 0.35-0.45;

[0029] And / or, the wear rate of the brake disc is <1μm / face*time.

[0030] Secondly, a method for manufacturing a brake disc is also provided, for manufacturing the brake disc as described above, comprising:

[0031] Provide raw materials for the structural layer and the friction layer;

[0032] The raw materials for the structural layer and the friction layer are laid in a mold and pressed to obtain a green body;

[0033] The green blank is sintered and hot-pressed to obtain the brake disc.

[0034] Optionally, before laying the raw materials for the structural layer and the friction layer in the mold, the method further includes:

[0035] The raw materials for the structural layer and the friction layer were ball-milled separately.

[0036] Optionally, the raw materials for the structural layer and the friction layer are laid in a mold and pressed, including:

[0037] The raw materials for the structural layer and the friction layer are laid in the mold;

[0038] At room temperature, press with a pressure of 200MPa-500MPa and hold for 1-5 minutes.

[0039] Optionally, the green body is sintered and hot-pressed, including:

[0040] In an inert atmosphere, the green body is sintered at 560℃-620℃ for 3-5 hours, then hot-pressed at 500℃-550℃ and 100MPa-300MPa for 10-30 seconds, and then cooled to room temperature.

[0041] According to a third aspect of this application, a brake is also provided, comprising the brake disc as described above, and / or a brake disc manufactured by the method described above.

[0042] According to a fourth aspect of this application, a vehicle is also provided, including the brakes described above.

[0043] The brake disc provided in this embodiment includes a structural layer and a friction layer disposed on at least one side of the structural layer. The structural layer and the friction layer satisfy: -2Hα m ≤Δα≤2Hαm In other words, the difference between the thermal expansion coefficients of the structural layer and the friction layer is related to the thicknesses of both the structural and friction layers, as well as the thermal expansion coefficient of the structural layer. A larger ratio between the thickness H2 of the friction layer and the thickness H1 of the structural layer allows for a larger difference (Δα) in their thermal expansion coefficients. Conversely, a smaller ratio between the thickness H2 of the friction layer and the thickness H1 of the structural layer allows for a smaller difference (Δα) in their thermal expansion coefficients. This embodiment of the application, by comprehensively considering the thicknesses and thermal expansion coefficients of the structural and friction layers, can control the thermal mismatch between the structural and friction layers within a suitable range, reducing the thermal mismatch, improving the bonding tightness between the structural and friction layers, reducing residual stress at the interface between the structural and friction layers during braking, and ensuring the performance stability of the brake disc.

[0044] Other features and advantages of this application will be described in detail in the following detailed description section. Detailed Implementation

[0045] The technical solutions described below, in conjunction with the embodiments of this application, will be clearly and completely described. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0046] This application provides a brake disc, including a structural layer and a friction layer disposed on at least one side of the structural layer. The structural layer and the friction layer satisfy: -2Hα m ≤Δα≤2Hα m ;

[0047] Where, Δα=α m -α f α m α represents the coefficient of thermal expansion of the structural layer. f H represents the coefficient of thermal expansion of the friction layer; H = H2 / H1, where H1 represents the thickness of the structural layer and H2 represents the thickness of the friction layer.

[0048] In other words, the difference between the thermal expansion coefficients of the structural layer and the friction layer is related to the thicknesses of both the structural and friction layers, as well as the thermal expansion coefficient of the structural layer. A larger ratio between the thickness H2 of the friction layer and the thickness H1 of the structural layer allows for a larger difference (Δα) in their thermal expansion coefficients. Conversely, a smaller ratio between the thickness H2 of the friction layer and the thickness H1 of the structural layer allows for a smaller difference (Δα) in their thermal expansion coefficients. This embodiment of the application, by comprehensively considering the thicknesses and thermal expansion coefficients of the structural and friction layers, can control the thermal mismatch between the structural and friction layers within a suitable range, reducing the thermal mismatch, improving the bonding tightness between the structural and friction layers, reducing residual stress at the interface between the structural and friction layers during braking, and ensuring the structural stability of the brake disc.

[0049] In some embodiments, 0.025 ≤ H2 / H1 ≤ 0.25. Setting the thickness of the structural layer and the friction layer in an appropriate ratio helps to improve the performance of the brake disc. Specifically, by controlling H2 / H1 within the above range, it is possible to ensure a small thermal mismatch between the structural layer and the friction layer, improve the bonding strength between the structural layer and the friction layer, reduce the thermal fade of the brake disc, and the thicker structural layer can provide good support for the friction layer, while the thinner friction layer can help to achieve a lighter brake disc while ensuring friction performance.

[0050] Specifically, when the thickness difference between the structural layer and the friction layer is large, the brake disc is prone to internal stress due to the difference in thermal expansion between the two layers under temperature changes. This can easily lead to problems such as deformation and cracking of the brake disc. Therefore, when the thickness difference between the structural layer and the friction layer is large—that is, when the ratio between the thickness H2 of the friction layer and the thickness H1 of the structural layer is small—the difference in the coefficients of thermal expansion between the structural layer and the friction layer should be kept within a small range to compensate for the internal stress caused by the excessive thickness difference and ensure the stability of the brake disc.

[0051] Conversely, when the thickness difference between the structural layer and the friction layer is small, the internal stress generated between the structural layer and the friction layer is small when the brake disc changes temperature. This can reduce problems such as deformation and cracking of the brake disc, and thus allow the thermal expansion coefficients of the structural layer and the friction layer to have a larger fluctuation range.

[0052] In some embodiments, the structural layer comprises aluminum alloy and a first ceramic material, wherein the first ceramic material accounts for V1 of the volume in the structural layer, where 0 < V1 ≤ 50%. Using aluminum alloy enables the structural layer to be lightweight, while including the first ceramic material in the structural layer helps improve its high-temperature performance and heat dissipation. By controlling the volume percentage of the first ceramic material in the structural layer to below 50%, the toughness, thermal stability, and structural strength of the structural layer can be guaranteed.

[0053] In some embodiments, the raw material of the friction layer includes a second ceramic material, wherein the volume percentage of the second ceramic material in the friction layer is V2, and 40% ≤ V2 ≤ 100%. The inclusion of a second ceramic material in the friction layer, and the second ceramic material accounting for more than 40% of the friction layer, enables the friction layer to have better high-temperature resistance and friction performance, maintains the stability of the brake disc during braking, and improves braking effect.

[0054] In some embodiments, the friction layer further includes aluminum alloy material and a third ceramic material, wherein the volume percentage of the third ceramic material in the friction layer is V3, and 40% ≤ V2 + V3 ≤ 100%. Adding aluminum alloy material to the friction layer improves thermal conductivity and wear resistance, contributing to the lightweighting of the brake disc. The friction layer also includes a third ceramic material, which can adjust the coefficient of thermal expansion, hardness, coefficient of friction, and toughness of the friction layer.

[0055] In some embodiments, the first ceramic material includes silicon carbide, the second ceramic material includes silicon carbide, and the coefficient of thermal expansion of the third ceramic material is greater than that of the second ceramic material. Silicon carbide has extremely high high-temperature resistance, maintaining stable physical and chemical properties at high temperatures. It also possesses high strength and hardness; therefore, its application in structural layers can improve structural stability and enhance the supporting performance of the structural layers. When applied to friction layers, silicon carbide can improve the coefficient of friction and wear resistance of the friction layers, and reduce the risk of thermal degradation.

[0056] The coefficient of thermal expansion of the third ceramic material is greater than that of the second ceramic layer material. Incorporating the third ceramic material into the friction layer can reduce the difference in thermal expansion coefficients between the friction layer and the structural layer, while ensuring the friction layer has a good coefficient of friction and good wear resistance. This reduces thermal mismatch between the two layers and improves their bonding strength.

[0057] In some embodiments, the coefficient of thermal expansion of the second ceramic material is C1, and the coefficient of thermal expansion of the third ceramic material is C2, wherein 2.3 × 10⁻⁶ -6 / ℃≤C2-C1≤10×10 -6 / ℃. By controlling the thermal expansion coefficients of the second and third ceramic materials to 2.3≤C2-C1≤10, the third ceramic material can better adjust the thermal expansion coefficient of the friction layer, reduce the difference in thermal expansion coefficients between the friction layer and the structural layer, and reduce the risk of thermal mismatch caused by excessive differences in thermal expansion coefficients between different materials in the friction layer.

[0058] In some embodiments, the structural layer and the friction layer satisfy Formula 1:

[0059]

[0060] Where a represents the thermal expansion coefficient of the third ceramic material, V1 represents the volume ratio of the first ceramic material in the structural layer, V2 represents the volume ratio of the second ceramic material in the friction layer, V3 represents the volume ratio of the third ceramic material in the friction layer, H = H2 / H1, H1 represents the thickness of the structural layer, and H2 represents the thickness of the friction layer.

[0061] By ensuring that the structural layer and the friction layer satisfy Formula 1, the thermal mismatch between the structural layer and the friction layer can be minimized, thereby improving the tightness of the bond between the structural layer and the friction layer and reducing the occurrence of problems such as cracking and damage of the brake disc during braking.

[0062] In some embodiments, the thickness H1 of the structural layer satisfies: 15mm ≤ H1 ≤ 60mm. When the thickness of the structural layer is within this range, the structural layer can provide sufficient strength and braking stability to ensure braking performance.

[0063] In some embodiments, the thickness of the structural layer is preferably 20mm-40mm. By controlling the thickness of the structural layer within the range of 20mm-40mm, it is possible to ensure that the structural layer can withstand greater stress while reducing its own weight.

[0064] For example, the thickness of the structural layer side can be 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm or 60mm.

[0065] In some embodiments, the thickness H2 of the friction layer satisfies: 0.5mm ≤ H2 ≤ 15mm. Controlling the thickness of the friction layer within this range provides sufficient friction and helps to achieve uniform wear.

[0066] In some embodiments, the thickness of the friction layer is preferably 2mm-10mm. By controlling the thickness of the friction layer within the range of 2mm-10mm, both its friction performance and good strength can be guaranteed.

[0067] In some embodiments, the aluminum alloy material includes at least one of binary aluminum alloys and six-series aluminum alloys. Using at least one of binary and six-series aluminum alloys can help form a denser structural layer and / or friction layer during the brake disc manufacturing process.

[0068] Two-series aluminum alloys are aluminum alloys with copper as the main alloying element, typically including aluminum-copper-magnesium alloys, aluminum-copper-manganese alloys, and aluminum-copper-magnesium-iron-nickel alloys, such as 2024 aluminum alloy, 2A16 (LY16) aluminum alloy, and 2A02 (LY6) aluminum alloy. Six-series aluminum alloys are aluminum alloys with magnesium and silicon as the main alloying elements, with Mg2Si as the main strengthening phase, such as 6061 aluminum alloy and 6063 aluminum alloy.

[0069] In some embodiments, the particle size of the aluminum alloy material is 5μm-20μm. Using aluminum alloy materials with smaller particle sizes, i.e., refining the grains, can improve the strength of the material itself, thereby increasing the structural strength of the brake disc. Furthermore, aluminum alloy materials within this particle size range can also improve wear resistance and increase thermal conductivity.

[0070] In some embodiments, the third ceramic material includes at least one of alumina, zirconium oxide, titanium carbide, and tungsten carbide. Alumina, zirconium oxide, titanium carbide, and tungsten carbide have higher coefficients of thermal expansion than silicon carbide. Doping the friction layer with at least one of these materials can reduce the difference in coefficients of thermal expansion between the friction layer and the structural layer while ensuring the friction performance of the friction layer. This helps to reduce the thermal mismatch between the friction layer and the structural layer and ensures the bonding strength between them.

[0071] In some embodiments, the particle size of the first ceramic material is 50 μm-300 μm. When the first ceramic material is controlled within this range, a stable coefficient of friction can be ensured, thermal fading problems can be reduced, and wear during braking can be better resisted, thereby extending the service life of the friction layer.

[0072] In some embodiments, the particle size of the second ceramic material is 50 μm-300 μm. Similar to the first ceramic material, when the second ceramic material is controlled within this range, a stable coefficient of friction can be ensured, thermal fading problems can be reduced, and wear during braking can be better resisted, thereby extending the service life of the friction layer.

[0073] In some embodiments, the particle size of the third ceramic material is 50 μm-300 μm. Similar to the first and second ceramic materials, when the third ceramic material is controlled within this range, a stable coefficient of friction can be ensured, thermal fading problems can be reduced, and wear during braking can be better resisted, thereby extending the service life of the friction layer.

[0074] In some embodiments, the friction layer includes a first friction layer and a second friction layer, which are respectively disposed on opposite sides of the structural layer. The thickness of the friction layer is the total thickness of the first and second friction layers.

[0075] By setting a first friction layer and a second friction layer on opposite sides of the structural layer, bi-directional braking can be achieved, thereby improving braking efficiency. Furthermore, bi-directional braking also helps maintain a balance of braking force, improving braking stability. In addition, setting a first friction layer and a second friction layer on opposite sides of the structural layer also helps ensure uniform friction and improve heat dissipation.

[0076] In some embodiments, the coefficient of friction of the brake disc is 0.35-0.45. Controlling the coefficient of friction of the brake disc within the range of 0.35-0.45 can achieve a stable braking effect and reduce the occurrence of lock-up during braking.

[0077] In some embodiments, the wear rate of the brake disc is <1 μm / face*time. By keeping the thermal mismatch between the structural layer and the friction layer within a certain range, the bonding tightness between the structural layer and the friction layer can be improved, resulting in a lower wear rate of the friction layer during use, thereby extending the service life of the brake disc.

[0078] Where μm / face*time represents the thickness of each face of the brake disc worn away in a single wear test.

[0079] Secondly, a method for manufacturing a brake disc is also provided, for manufacturing the brake disc as described above, comprising:

[0080] Provide raw materials for the structural layer and the friction layer;

[0081] The raw materials for the structural layer and the friction layer are laid in a mold and pressed to obtain a green body;

[0082] The green blank is sintered and hot-pressed to obtain the brake disc.

[0083] The raw materials for the structural layer and the friction layer include:

[0084] The raw materials for the structural layer and the friction layer are prepared separately according to the specified proportions. For example, aluminum alloy material and the first ceramic material are compounded according to the specified proportions to obtain the raw materials for the structural layer, and aluminum alloy material, the first ceramic material and the second ceramic material are compounded according to the specified proportions to obtain the raw materials for the friction layer.

[0085] In some embodiments, before laying the raw materials for the structural layer and the friction layer in the mold, the method further includes:

[0086] The raw materials for the structural layer and the friction layer were ball-milled separately.

[0087] After ball milling the raw materials for the structural layer and the friction layer respectively, the raw materials can be further refined and crushed, and the different components in the raw materials can be mixed evenly. The ball milling process can also modify the surface of the raw materials, making the surface of the raw materials smoother and more uniform.

[0088] For example, in an inert atmosphere, the raw materials of the structural layer and the friction layer are ball-milled using cemented carbide, wherein the ball-to-material ratio is set to (3-10):1 and the ball-milling time is 4-6 hours.

[0089] In some embodiments, the raw materials for the structural layer and the friction layer are laid in a mold and pressed, including:

[0090] The raw materials for the structural layer and the friction layer are laid in the mold;

[0091] At room temperature, press with a pressure of 200MPa-500MPa and hold for 1-5 minutes.

[0092] Pressing at room temperature allows the structural and friction layers to be initially formed, creating a green body that facilitates subsequent operations. Pressing under pressure of 200MPa-500MPa and holding the pressure for 1-5 minutes densifies the raw material and fixes it into the desired shape in the mold, ensuring that the particles in the raw material are fully combined to obtain a structurally stable green body.

[0093] In some embodiments, sintering and hot pressing of the green compact includes:

[0094] In an inert gas atmosphere, the green compact is sintered at 560℃-620℃ for 3-5 hours, then hot-pressed at 500℃-550℃ and 100MPa-300MPa for 10-30 seconds, and then cooled to room temperature.

[0095] Sintering in an inert atmosphere reduces the reaction between the raw materials and the external environment. Setting the sintering temperature at 560℃-620℃ and the sintering time at 3-5 hours allows the raw materials in the structural and friction layers to bond together through surface diffusion, volume diffusion, and grain boundary migration, forming a dense whole. After sintering, hot pressing at 500℃-550℃ further densifies the structural and friction layers, improving density and mechanical properties. The 500℃-550℃ temperature promotes plastic deformation in the structural and friction layers, while the 100MPa-300MPa pressure ensures closer contact between the raw material particles, promoting particle bonding. Through the combined effect of temperature and pressure, density and mechanical properties are significantly improved. At higher temperature and pressure conditions, the plastic deformation and densification processes occur rapidly; therefore, holding the pressure for only 10-30 seconds is sufficient.

[0096] According to a third aspect of this application, a brake is also provided, comprising the brake disc described above, and / or a brake disc manufactured by the method described above. This brake possesses all the beneficial effects of the aforementioned brake disc, which will not be elaborated further herein.

[0097] According to a fourth aspect of this application, a vehicle is also provided, including the brake as described above. This vehicle possesses all the beneficial effects of the aforementioned brake disc, which will not be elaborated further herein.

[0098] The brake disc provided in this application will be described below with reference to specific embodiments.

[0099] It should be noted that, unless otherwise specified, the percentages in the embodiments and comparative examples are all volume percentages.

[0100] Example 1

[0101] In this embodiment, the raw materials for the structural layer include 70% 6061 aluminum alloy powder and 30% silicon carbide powder. The raw materials for the friction layer include 30% 6061 aluminum alloy powder, 55% silicon carbide powder, and 15% alumina powder.

[0102] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0103] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0104] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 6mm.

[0105] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0106] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0107] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0108] Example 2

[0109] In this embodiment, the raw materials for the structural layer include 70% 6061 aluminum alloy powder and 30% silicon carbide powder. The raw materials for the friction layer include 40% 6061 aluminum alloy powder, 30% silicon carbide powder, and 30% alumina powder.

[0110] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0111] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0112] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 6mm.

[0113] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0114] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0115] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0116] Example 3

[0117] In this embodiment, the raw materials for the structural layer include 70% 6061 aluminum alloy powder and 30% silicon carbide powder. The raw materials for the friction layer include 40% 6061 aluminum alloy powder, 30% silicon carbide powder, and 30% zirconium oxide powder.

[0118] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0119] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0120] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 6mm.

[0121] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0122] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0123] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0124] Example 4

[0125] In this embodiment, the structural layer is made of 100% 6061 aluminum alloy powder. The friction layer is made of 50% 6061 aluminum alloy powder, 10% silicon carbide powder, and 40% zirconium oxide powder.

[0126] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0127] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0128] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 6mm.

[0129] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0130] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0131] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0132] Example 5

[0133] In this embodiment, the structural layer comprises 70% 2024 aluminum alloy powder and 30% silicon carbide powder. The friction layer comprises 40% 2024 aluminum alloy powder, 30% silicon carbide powder, and 30% zirconium oxide powder.

[0134] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0135] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0136] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 6mm.

[0137] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0138] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0139] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0140] Example 6

[0141] In this embodiment, the structural layer comprises 70% 6061 aluminum alloy powder and 30% silicon carbide powder. The friction layer comprises 40% 6061 aluminum alloy powder, 30% silicon carbide powder, and 30% zirconium oxide powder.

[0142] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0143] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0144] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 6mm.

[0145] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0146] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0147] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0148] Comparative Example 1

[0149] In this comparative example, the structural layer consists of 50% 6061 aluminum alloy powder and 50% silicon carbide powder. The friction layer consists of 20% 6061 aluminum alloy powder and 80% silicon carbide powder.

[0150] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0151] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0152] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 5mm.

[0153] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0154] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0155] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0156] Comparative Example 2

[0157] In this comparative example, the structural layer consists of 70% 6061 aluminum alloy powder and 30% silicon carbide powder. The friction layer consists of 20% 6061 aluminum alloy powder, 70% silicon carbide powder, and 10% zirconium oxide powder.

[0158] (1) Prepare the raw materials for the structural layer and the friction layer according to the proportions;

[0159] (2) Under the condition of ball-to-material ratio of 5:1, the raw materials of the structural layer and the friction layer were ball-milled with cemented carbide for 5 hours respectively;

[0160] (3) The above raw materials are laid in the mold according to the three-layer structure of the first friction layer, the structural layer and the second friction layer, wherein the thickness of the structural layer is 30mm and the total thickness of the first friction layer and the second friction layer is 3mm.

[0161] (4) Place the mold after laying the raw materials on the hydraulic press platform, hold the pressure at 300MPa for 3 minutes, and press to obtain the green blank;

[0162] (5) Transfer the mold and the green blank together to an inert atmosphere sintering furnace, sinter at 600°C for 3 hours, cool to 500°C, transfer to a hot press under an argon atmosphere, hold pressure at 500°C and 150MPa for 30 seconds, and then cool to room temperature under an argon atmosphere to obtain a brake disc blank.

[0163] (6) Take out the brake disc blank and perform machining, dimensional processing and surface polishing to obtain the brake disc.

[0164] The bonding strength between the structural layer and the friction layer in the brake discs of Examples 1-6 and Comparative Examples 1-2, as well as the coefficient of friction and wear rate of the brake discs, were tested. The bonding strength between the structural layer and the friction layer was tested according to the test method in GB / T 5210-2006. The coefficient of friction and wear rate of the brake discs were tested according to the test method in T / CAAMTB 90-2002. The results are shown in Table 1.

[0165] Table 1. Comparison of test results for different embodiments and comparative examples.

[0166]

[0167]

[0168] In Table 1, α m α represents the coefficient of thermal expansion of the structural layer.f The coefficient of thermal expansion of the friction layer is represented by Δα = α m -α f The thermal mismatch is:

[0169] As shown in Table 1, in the brake discs of Examples 1-6, the condition -2Hα is satisfied between both the structural layer and the friction layer. m ≤Δα≤2Hα m Under the given conditions, the bonding strength between the structural layer and the friction layer in the brake disc meets the requirements of T / CAAMTB 90-2002 standard, and the friction coefficient and wear rate of the brake disc both meet the requirements of GB / T34422-2017 standard. No cracking issues were observed in the brake disc. However, Comparative Examples 1 and 2 did not meet the -2Hα standard. m ≤Δα≤2Hα m The conditions were not met, and cracking issues existed. Furthermore, the bonding strength, friction coefficient, and wear rate were significantly lower than those of Examples 1-6, failing to meet the standard requirements.

[0170] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0171] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0172] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0173] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A brake disc, characterized in that The structure layer and the friction layer are arranged on at least one side of the structure layer. The structure layer and the friction layer satisfy: -2Hα m ≤ Δα ≤ 2Hα m ; where Δα = α m -α f , α m represents the coefficient of thermal expansion of the structure layer, α f represents the coefficient of thermal expansion of the friction layer; H = H2 / H1, H1 represents the thickness of the structure layer, H2 represents the thickness of the friction layer.

2. The brake disc of claim 1, wherein, 0.025≤H2 / H1≤0.

25.

3. A brake disc according to claim 1 or 2, characterised in that, The raw material of the structure layer comprises an aluminum alloy material and a first ceramic material, wherein the volume ratio of the first ceramic material in the structure layer is V1, 0 And / or, the raw material of the friction layer comprises a second ceramic material, wherein the volume ratio of the second ceramic material in the friction layer is V2, 40%≤V2≤100%.

4. The brake disc of claim 3, wherein, The friction layer further comprises the aluminum alloy material and a third ceramic material, and the volume ratio of the third ceramic material in the friction layer is V3, 40%≤V2+V3≤100%.

5. A brake disc according to claim 4, wherein, The first ceramic material comprises silicon carbide, and the second ceramic material comprises silicon carbide. The thermal expansion coefficient of the third ceramic material is greater than the thermal expansion coefficient of the second ceramic material.

6. The brake disc of claim 5, wherein, The second ceramic material has a coefficient of thermal expansion C1 and the third ceramic material has a coefficient of thermal expansion C2, wherein 2.3 x 10 -6 / °C ≤ C2 - C1 ≤ 10 x 10 -6 / °C.

7. The brake disc of claim 5, wherein, The structure layer and the friction layer satisfy: Wherein, a represents the thermal expansion coefficient of the third ceramic material.

8. The brake disc of claim 1, wherein, The thickness H1 of the structure layer satisfies: 15mm≤H1≤60mm. And / or, the thickness H2 of the friction layer satisfies: 0.5mm≤H2≤15mm.

9. A brake disc according to claim 8, characterised in that, The thickness H1 of the structure layer satisfies: 20mm≤H1≤40mm. And / or, the thickness H2 of the friction layer satisfies: 2mm≤H2≤10mm.

10. The brake disc of claim 3, wherein, The aluminum alloy material comprises at least one of a two-system aluminum alloy material and a six-system aluminum alloy material. And / or, the particle size of the aluminum alloy material is 5μm-20μm.

11. The brake disc of claim 4, wherein, The third ceramic material comprises at least one of alumina, zirconia, titanium carbide and tungsten carbide.

12. The brake disc of claim 11, wherein, The particle size of the first ceramic material is 50μm-300μm. And / or, the particle size of the second ceramic material is 50μm-300μm. And / or, the particle size of the third ceramic material is 50μm-300μm.

13. The brake disc of any of claims 1-2 or 4-12, wherein, The friction layer comprises a first friction layer and a second friction layer, and the first friction layer and the second friction layer are arranged on opposite sides of the structure layer. The thickness of the friction layer is the total thickness of the first friction layer and the second friction layer.

14. The brake disc of claim 13, wherein, The friction coefficient of the brake disc is 0.35-0.

45. And / or, the wear rate of the brake disc is <1μm / surface*times.

15. A method for producing a brake disc for producing a brake disc according to any one of claims 1 to 14, characterized in that Comprising: providing raw materials of the structure layer and raw materials of the friction layer; laying the raw materials of the structure layer and the raw materials of the friction layer in a mold, and pressing to obtain a green body; sintering and hot pressing the green body to obtain a brake disc.

16. The method of claim 15, wherein Before laying the raw materials of the structure layer and the raw materials of the friction layer in the mold, further comprising: ball milling the raw materials of the structure layer and the raw materials of the friction layer respectively.

17. The method of claim 15, wherein the brake disc is prepared by, Laying the raw materials of the structure layer and the raw materials of the friction layer in the mold, and pressing, comprising: laying the raw materials of the structure layer and the raw materials of the friction layer in the mold; pressing at a pressure of 200MPa-500MPa at room temperature, and holding for 1min-5min.

18. The method of claim 15, wherein the brake disc is made of a material selected from the group consisting of cast iron, steel, and aluminum. Sintering and hot pressing the green body, comprising: The green body is sintered at 560-620 ℃ for 3-5 h in an inert atmosphere, and then hot-pressed at 500-550 ℃ and 100-300 MPa, with pressure holding for 10-30 s, and then cooled to room temperature.

19. A brake characterized by A brake disc comprising the brake disc according to any one of claims 1-14, and / or a brake disc produced by the method according to any one of claims 15-18.

20. A vehicle characterized by A brake comprising the brake disc according to claim 19.

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