Composite bushing for automobile and manufacturing method thereof

Abstract

The invention belongs to the technical field of automobile parts, and discloses a composite bushing for an automobile and a manufacturing method thereof.The composite bushing comprises a metal base body, an elastic rubber layer is arranged on the outer surface of the metal base body, a fabric reinforcing layer is arranged on the outer side of the elastic rubber layer, a waterproof breathable film is arranged on the outer surface of the fabric reinforcing layer, and a wear-resistant protective layer is arranged on the outer surface of the waterproof breathable film; the problem that in the prior art, a traditional automobile lining made of a single material cannot meet the comprehensive requirements of modern automobiles for high performance, multi-working-condition adaptability and high reliability is solved, and the automobile lining is suitable for automobile parts.

Description

Technical Field

[0001] The invention relates to the technical field of automobile parts, in particular to a composite bushing for automobiles and a manufacturing method thereof. Background Art

[0002] With the rapid development of the automobile industry, modern automobiles have increasingly stringent performance requirements for various components. As an important component connecting key system components such as automobile transmission and suspension, the performance of automobile bushings directly affects the overall performance, comfort, safety and durability of the automobile.

[0003] In the traditional design of automobile bushings, they are mainly made of a single material, such as metal bushings and rubber bushings. Metal bushings (such as common steel bushings) have high strength and rigidity, can withstand large loads, and have certain advantages in some parts with high structural support requirements. However, the shock absorption and buffering performance of metal bushings is extremely poor. During the driving process of the car, it cannot effectively absorb the impact and vibration caused by road bumps, engine vibrations, etc. This will not only cause the passengers in the car to feel obvious bumps and noise, reducing the ride comfort, but also cause fatigue damage to the connecting parts due to long-term severe vibration, shortening the service life, increasing the maintenance cost of the car and safety hazards.

[0004] In contrast, rubber bushings are widely used for their excellent elasticity and shock absorption performance. Rubber materials can effectively absorb and buffer various vibrations and shocks, significantly improving the driving comfort of the car. However, the strength and wear resistance of rubber bushings are relatively weak. When subjected to large loads or long-term use, they are prone to deformation, wear and even cracking. They cannot meet the use requirements of the car under high-performance conditions. For example, in high-performance sports cars or heavy trucks, the limitations of rubber bushings are more obvious. Frequent high-intensity use will cause them to fail quickly, affecting the handling stability and safety of the car.

[0005] In addition, with the increasing degree of automobile electrification, static electricity issues are also receiving increasing attention. Metal bushings are prone to electrostatic discharge due to their good conductivity, which may cause electromagnetic interference to the electronic control system of the car and affect the normal operation of electronic equipment; while the insulation of rubber bushings makes it easy for static electricity to accumulate on their surface, which will also cause potential harm to surrounding electronic components, such as causing sensor misjudgment, electronic component breakdown and other failures.

[0006] At the same time, cars are operating under different environmental conditions, facing the test of temperature changes, humidity, dust and other factors. It is difficult for a bushing made of a single material to have good temperature resistance, water resistance and dust resistance at the same time. For example, rubber bushings are prone to aging and softening in high temperature environments, and they will become hard and brittle in low temperature environments, resulting in a significant decline in performance; although metal bushings have good temperature resistance, they are prone to rust and corrosion in humid environments, affecting their mechanical properties and connection reliability.

[0007] In summary, traditional single-material automobile bushings can no longer meet the comprehensive requirements of modern automobiles for high performance, adaptability to multiple working conditions, and high reliability. Therefore, developing a composite automobile bushing that combines high strength, good shock absorption and buffering performance, wear resistance, corrosion resistance, antistatic properties, and adaptability to multiple environmental conditions has become a key technical issue that needs to be urgently solved in the field of automobile parts, which has extremely important practical significance and broad application prospects.

[0008] Therefore, a composite bushing for automobiles having multiple excellent properties and a manufacturing method thereof are proposed to solve the above problems. Summary of the invention

[0009] The present invention aims to provide a composite bushing for automobiles and a method for manufacturing the same, so as to solve the problem that conventional single-material automobile bushings in the prior art can no longer meet the comprehensive requirements of modern automobiles for high performance, multi-operating condition adaptability and high reliability.

[0010] In order to achieve the above object, the present invention provides the following technical solutions:

[0011] The technical solution provided by the present invention is: a composite bushing for automobiles, comprising a metal substrate, an elastic rubber layer is provided on the outer surface of the metal substrate, a fabric reinforcement layer is provided on the outer side of the elastic rubber layer, a waterproof breathable membrane is provided on the outer surface of the fabric reinforcement layer, and a wear-resistant protective layer is provided on the outer surface of the waterproof breathable membrane;

[0012] The metal substrate is made of titanium alloy and has a cylindrical structure. A spiral groove is provided on the outer surface of the metal substrate along the axial direction. The depth of the spiral groove is between 0.5mm and 1.5mm. The spiral groove is filled with shock-absorbing damping material. Both ends of the metal substrate are provided with connecting ears extending outward. A plurality of connecting holes are evenly arranged on the connecting ears. The inner wall of the connecting hole has a thread strengthening coating to enhance the reliability of the connection.

[0013] The elastic rubber layer is coated on the outer surface of the metal substrate. The elastic rubber layer is made of a blend of silicone rubber and polyurethane rubber, with a thickness of 4mm-6mm, wherein the mass ratio of silicone rubber to polyurethane rubber is 3:7. The outer surface of the elastic rubber layer has a number of equally distributed annular ridges, the height of the annular ridges is 1mm-2mm, and the spacing between adjacent annular ridges is 3mm-5mm. Conductive carbon fiber filaments are evenly dispersed in the elastic rubber layer. The diameter of the conductive carbon fiber filaments is 5μm-10μm, and the mass fraction accounts for 3%-5% of the total mass of the rubber layer, which is used to dissipate static electricity.

[0014] The fabric reinforcement layer is attached to the outer surface of the elastic rubber layer. The fabric reinforcement layer is blended by aramid fiber and glass fiber. The mass ratio of aramid fiber to glass fiber is 4:6. The warp and weft density of the fabric reinforcement layer is 100-150 strands / inch. The fabric reinforcement layer is treated with a special silane coupling agent to improve the bonding force with the rubber layer. The outer surface of the fabric reinforcement layer is coated with a waterproof and breathable membrane to prevent moisture intrusion and ensure gas exchange.

[0015] The wear-resistant protective layer is wrapped on the outer surface of the waterproof and breathable membrane. The wear-resistant protective layer is made of a blend of polytetrafluoroethylene and ultra-high molecular weight polyethylene with a thickness of 2mm-3mm. The mass ratio of polytetrafluoroethylene to ultra-high molecular weight polyethylene in the blend is 1:4. The outer surface of the wear-resistant protective layer has a micro-texture structure, which is a diamond grid with a grid side length of 0.5mm-1mm to improve anti-slip performance and wear resistance.

[0016] Furthermore, the shock-absorbing and damping material is a high molecular polymer damping material, the loss factor of which is between 0.5 and 0.8, and can maintain stable damping performance within a temperature range of -40°C to 120°C.

[0017] Furthermore, the elastic rubber layer and the metal substrate are tightly bonded through a vulcanization process, the vulcanization temperature is 150° C.-170° C., the vulcanization time is 30 minutes-60 minutes, and the pressure is 10 MPa-15 MPa.

[0018] Furthermore, the aramid fibers and glass fibers of the fabric reinforcement layer are both filament fibers with a length between 10 mm and 20 mm, and the fibers are interwoven to form a stable mesh structure.

[0019] Furthermore, a hot pressing bonding process is adopted between the wear-resistant protective layer and the fabric reinforcement layer, the hot pressing temperature is 180°C-200°C, the hot pressing pressure is 8MPa-12MPa, and the hot pressing time is 20 seconds-40 seconds.

[0020] Furthermore, a composite bushing for an automobile and a method for manufacturing the same include the following steps:

[0021] S1: Processing the metal substrate: first, the titanium alloy raw material is made into a cylindrical metal substrate blank through forging and machining processes, and then a spiral groove with a depth of 0.5mm-1.5mm is processed on the outer surface of the metal substrate blank by CNC machining equipment, and then a high molecular polymer damping material is filled in the spiral groove, and then both ends of the metal substrate are processed to form a connecting ear extending outward, and a plurality of connecting holes are drilled on the connecting ear, and finally a thread strengthening coating is formed on the inner wall of the connecting hole through an electroplating process;

[0022] S2: forming the elastic rubber layer, blending silicone rubber and polyurethane rubber in a mass ratio of 3:7, adding conductive carbon fiber filaments with a diameter of 5 μm-10 μm and a mass fraction of 3%-5% of the total mass of the rubber layer, mixing in an internal mixer at 100°C-120°C for 20 minutes-30 minutes, and after mixing evenly, coating the rubber material on the processed metal substrate through an extrusion process to form an elastic rubber layer with a thickness of 4mm-6mm, and at the same time, providing an annular ridge structure on the extrusion die to form an annular ridge with a height of 1mm-2mm and an adjacent spacing of 3mm-5mm on the outer surface of the elastic rubber layer, and then placing the metal substrate coated with the rubber layer into a vulcanization device, and vulcanizing at 150°C-170°C for 30 minutes-60 minutes at a pressure of 10MPa-15MPa;

[0023] S3: The fabric reinforcement layer is bonded to the surface of the elastic rubber layer. Aramid fiber and glass fiber are blended into filament fiber in a mass ratio of 4:6. The fiber length is between 10 mm and 20 mm. The warp and weft density is 100 strands / inch to 150 strands / inch. The blended fiber fabric is then treated with a silane coupling agent. After treatment, the fabric is bonded to the outside of the vulcanized elastic rubber layer through a glue coating process. The glue coating amount is 80 g / m 2 -120g / m 2 After lamination, a waterproof and breathable membrane is formed on the outer surface of the fabric reinforcement layer by spraying process;

[0024] S4: Wear-resistant protective layer molding. After polytetrafluoroethylene and ultra-high molecular weight polyethylene are blended in a mass ratio of 1:4, the blended material is molded into a wear-resistant protective layer with a thickness of 2mm-3mm through an injection molding process. A diamond grid-like micro-texture structure with a grid side length of 0.5mm-1mm is set on the injection mold. The molded wear-resistant protective layer is then attached to the outside of the fabric reinforcement layer through a hot pressing process. The hot pressing temperature is 180℃-200℃, the hot pressing pressure is 8MPa-12MPa, and the hot pressing time is 20 seconds-40 seconds.

[0025] Furthermore, in S1, the forging ratio of the forging process is controlled at 5-8, and the cutting parameters of the machining process are set according to the dimensional accuracy requirements of the metal substrate to ensure the machining accuracy and surface quality of the metal substrate.

[0026] Furthermore, in S2, the rotor speed of the internal mixer is controlled at 40 rpm-60 rpm, and the extrusion speed of the extrusion process is adjusted according to the thickness of the rubber layer and the molding requirements of the annular ridges to ensure the quality uniformity and appearance quality of the elastic rubber layer.

[0027] Furthermore, in S3, the treatment time of the silane coupling agent is 10 minutes to 20 minutes, the treatment temperature is 80°C to 100°C, the glue used in the gluing process is a special glue for rubber, and the tightness of the bonding between the fabric reinforcement layer and the elastic rubber layer is ensured by a rolling process during the bonding process.

[0028] Furthermore, in S4, the injection molding process has an injection speed of 20 cm 3 / s-30cm 3 / s, the holding time is 10 seconds to 20 seconds, the heating rate of the hot pressing process is 10℃ / s-20℃ / s, and the cooling rate is 8℃ / s-15℃ / s to ensure the molding quality of the wear-resistant protective layer and the fitting effect with the fabric reinforcement layer.

[0029] The beneficial effects of this technical solution are:

[0030] (1) The composite bushing of the present invention combines the high strength of the metal matrix, the good shock-absorbing and buffering performance of the elastic rubber layer, the high-strength tear-resistant characteristics of the fabric reinforcement layer, and the excellent wear resistance and anti-skid performance of the wear-resistant protective layer through a unique multi-layer structural design. Compared with the traditional single-material bushing, it shows a good balance in mechanical properties such as tensile strength and compression modulus. It has sufficient strength to support the connection and movement of various parts of the car, and can effectively buffer and absorb vibration, significantly improving the overall performance and comfort of the car. For example, when used in the automobile suspension system, it can effectively reduce the impact force transmitted to the car body by road bumps, making the vehicle run more smoothly and better in handling.

[0031] (2) The elastic rubber layer adopts a special blended rubber formula, combined with a high molecular polymer damping material filled with internal spiral grooves and an annular ridge structure on the outer surface, which shows excellent shock absorption efficiency in a wide temperature range, up to 85%-90%. This high-efficiency shock absorption performance can effectively reduce the vibration and noise caused by engine operation, uneven road surface and vehicle braking during driving. It not only provides a quiet and comfortable in-car environment for drivers and passengers, but also reduces the fatigue damage of vibration to other parts of the car, thereby extending the service life of the car and reducing maintenance costs.

[0032] (3) The wear-resistant protective layer is made of a blend of polytetrafluoroethylene and ultra-high molecular weight polyethylene and has a diamond-shaped grid-like micro-texture structure on its surface, which greatly improves the wear resistance of the bushing. The wear loss is only 6-8 mg / 1000 cycles, which is significantly improved compared to traditional rubber bushings and can adapt to long-term use of vehicles under various complex road conditions. At the same time, the conductive carbon fiber fibers in the elastic rubber layer give the bushing good anti-static properties, and the surface resistance is controlled between 5×10^6-8×10^7Ω, which effectively avoids the interference and damage of static electricity accumulation to automotive electronic equipment, ensures the stable operation of the automotive electronic system, and improves the safety and reliability of the vehicle.

[0033] (4) The rational selection and special treatment of the materials of each layer make the composite bushing have excellent temperature resistance. It can work normally in a wide temperature range of -40℃-120℃. It can maintain stable performance regardless of the cold winter or the hot summer. The waterproof and breathable membrane outside the fabric reinforcement layer and the corrosion resistance of the metal matrix make the bushing have good waterproof, dustproof and rust-proof capabilities. It can operate reliably under harsh environmental conditions such as humidity and dust, greatly improving the applicability of the vehicle in different regions and climatic conditions.

[0034] (5) Since the layers are tightly connected through optimized connection processes, such as the vulcanization process of the elastic rubber layer and the metal matrix, the rubber coating roller pressing process of the fabric reinforcement layer and the elastic rubber layer, and the hot pressing process of the wear-resistant protective layer and the fabric reinforcement layer, the overall structural stability of the composite bushing is extremely high. In the fatigue life test, it can reach 1.5×10^6-2×10^6 cycles, and the tear strength is 120-150kN / m, which is much better than traditional rubber bushings. It can withstand various complex stresses and frequent dynamic load changes during the long-term operation of the vehicle, reducing the risk of failure of the bushing due to structural damage, improving the operating reliability and durability of the vehicle, and reducing the use cost and maintenance frequency of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic structural diagram of a composite bushing for automobiles and a manufacturing method thereof proposed by the present invention;

[0036] Figure 2 A schematic cross-sectional structure diagram of a composite bushing for automobiles and a manufacturing method thereof proposed by the present invention;

[0037] Figure 3 A schematic diagram of a layered cross-sectional structure of a composite bushing for automobiles and a manufacturing method thereof proposed by the present invention;

[0038] Figure 4 This is a schematic plan view of the structure of a composite bushing for automobiles and a manufacturing method thereof proposed by the present invention;

[0039] Figure 5 This is a comparison table of experimental data of an embodiment of a composite bushing for automobiles and a manufacturing method thereof proposed by the present invention;

[0040] Figure 6 This is a comparison table of experimental data of a composite bushing for automobiles and a manufacturing method thereof proposed by the present invention and a traditional bushing.

[0041] The names of the corresponding marks in the accompanying drawings are: 1. Metal substrate; 2. Elastic rubber layer; 3. Fabric reinforcement layer; 4. Waterproof and breathable membrane; 5. Wear-resistant protective layer; 101. Spiral groove; 102. Connecting ear; 103. Connecting hole; 201. Annular ridge; 501. Micro-texture structure. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The specific implementation process is as follows:

[0044] Embodiment 1:

[0045] See also Figure 1-6 The present invention provides a technical solution: a composite bushing for automobiles, including a metal substrate 1, which is made of titanium alloy and has good strength and corrosion resistance. The metal substrate 1 is cylindrical in shape, and a plurality of spiral grooves 101 are processed along the axial direction on the outer surface. The depth of the spiral grooves 101 is between 0.5 mm and 1.5 mm. The spiral grooves 101 are filled with shock-absorbing and damping materials. The shock-absorbing and damping materials are high molecular polymer damping materials, and the loss factor is between 0.5 and 0.8. The damping performance can be kept stable in a wide temperature range of -40°C to 120°C, and the vibration energy can be effectively absorbed and dissipated. The two ends of the metal substrate 1 are provided with connecting ears 102 extending outward, and the connecting ears 102 are evenly distributed with a plurality of connecting holes 103. The inner wall of the connecting hole 103 is formed with a thread strengthening coating by an electroplating process, which greatly enhances the reliability of the connection and facilitates a stable connection with other parts of the automobile.

[0046] The elastic rubber layer 2 is coated on the outside of the metal substrate 1, and is made of silicone rubber and polyurethane rubber mixed in a mass ratio of 3:7, and has a thickness of 4mm-6mm. This mixed rubber combines the high temperature resistance and aging resistance of silicone rubber with the high elasticity and high strength characteristics of polyurethane rubber. The outer surface of the elastic rubber layer 2 has a number of equally distributed annular ridges 201, the height of the annular ridges 201 is 1mm-2mm, and the spacing between adjacent annular ridges 201 is 3mm-5mm. These annular ridges 201 help to further disperse and buffer external forces in different directions. At the same time, conductive carbon fiber filaments are evenly dispersed in the elastic rubber layer 2, and the diameter of the conductive carbon fiber filaments is 5μm-10μm, and the mass fraction accounts for 3%-5% of the total mass of the elastic rubber layer 2, which can effectively dissipate static electricity and prevent static electricity accumulation from interfering with or damaging automotive electronic equipment;

[0047] The fabric reinforcement layer 3 is attached to the outside of the elastic rubber layer 2. It is blended by aramid fiber and glass fiber in a mass ratio of 4:6. The warp and weft density is 100-150 strands / inch. Both aramid fiber and glass fiber are filament fibers with a length of 10mm-20mm. The two are interwoven to form a stable mesh structure, which greatly improves the overall strength and tear resistance of the bushing. The fabric reinforcement layer 3 is treated with a special silane coupling agent for 10 minutes-20 minutes at a temperature of 80℃-100℃, which effectively improves the adhesion with the rubber layer and ensures the coordinated work between the layers. The outer surface of the fabric reinforcement layer 3 is coated with a waterproof and breathable membrane 4, which can prevent moisture from invading the interior of the bushing and causing the material performance to deteriorate, and can also ensure gas exchange and maintain the stability of the bushing under different environmental conditions.

[0048] The outermost layer is a wear-resistant protective layer 5, which is made of a blend of polytetrafluoroethylene and ultra-high molecular weight polyethylene in a mass ratio of 1:4, with a thickness of 2mm-3mm. The blend has excellent wear resistance and self-lubrication, and its outer surface has a micro-texture structure 501 in a diamond grid shape with a grid side length of 0.5mm-1mm. This micro-texture structure 501 significantly improves the anti-skid performance and wear resistance, effectively prolongs the service life of the bushing, and enables it to meet the running requirements of the car under various road conditions;

[0049] The elastic rubber layer 2 and the metal substrate 1 are tightly bonded through a vulcanization process, the vulcanization temperature is 150°C-170°C, the vulcanization time is 30 minutes-60 minutes, and the pressure is 10MPa-15MPa. During the vulcanization process, the rubber molecules react chemically with the surface of the metal substrate 1 to form a strong chemical bond, ensuring that the elastic rubber layer 2 will not peel off or slip from the metal substrate 1 during long-term use;

[0050] The fabric reinforcement layer 3 and the elastic rubber layer 2 are connected by a glue coating process, and the amount of glue coating is 80g / m 2 -120g / m2 The rolling process is used to ensure tightness of the fit. The gluing process uses special rubber glue, which can form a good bonding interface between the fabric reinforcement layer 3 and the elastic rubber layer 2. The rolling process further eliminates the air and gap between the two layers, so that the two layers fit closely and jointly bear the external force.

[0051] A hot pressing bonding process is adopted between the wear-resistant protective layer 5 and the fabric reinforcement layer 3. The hot pressing temperature is 180°C-200°C, the hot pressing pressure is 8MPa-12MPa, and the hot pressing time is 20 seconds-40 seconds. The hot pressing process allows the blended material of the wear-resistant protective layer 5 to be fully integrated with the surface of the fabric reinforcement layer 3 under high temperature and high pressure to form a stable bonding layer, ensuring that the wear-resistant protective layer 5 can effectively protect the internal layers of the structure, and at the same time, it can also be firmly attached to the surface of the bushing;

[0052] A composite bushing for automobiles and a manufacturing method thereof, firstly, a titanium alloy raw material is made into a cylindrical metal matrix 1 blank through forging and machining processes, the forging ratio of the forging process is controlled at 5-8, and the internal structure of the titanium alloy is made more dense and uniform by reasonably controlling the forging ratio, and the comprehensive performance of the metal matrix 1 is improved. The cutting parameters of the machining process are optimized according to the dimensional accuracy requirements of the metal matrix 1, such as selecting a suitable cutting speed, feed rate and cutting depth to ensure the machining accuracy and surface quality of the metal matrix 1, and ensure the subsequent spiral groove 1 01 processing and forming accuracy of the connecting ear 102 and the connecting hole 103, and then a spiral groove 101 with a depth of 0.5mm-1.5mm is processed on the outer surface of the metal substrate 1 blank by CNC processing equipment, and then a high molecular polymer damping material is filled in the spiral groove 101, and then the two ends of the metal substrate 1 are processed to form a connecting ear 102 extending outward, and a plurality of connecting holes 103 are drilled on the connecting ear 102, and finally a thread strengthening coating is formed on the inner wall of the connecting hole 103 by electroplating process to enhance the reliability of the connection;

[0053] The elastic rubber layer 2 is formed, silicone rubber and polyurethane rubber are blended in a mass ratio of 3:7, and conductive carbon fiber filaments with a diameter of 5 μm-10 μm are added at a mass fraction of 3%-5% of the total mass of the rubber layer. The mixture is kneaded in an internal mixer at 100° C.-120° C. for 20 minutes-30 minutes. The rotor speed of the internal mixer is controlled at 40 rpm-60 rpm. The rubber material and the conductive carbon fiber filaments are fully and uniformly mixed by precisely controlling the kneading temperature, time and rotor speed. After the kneading is uniform, the rubber material is coated on the processed metal substrate 1 through an extrusion process to form a 4 mm-6 mm thick layer. The elastic rubber layer 2, the extrusion speed of the extrusion process is adjusted according to the thickness of the rubber layer and the molding requirements of the annular ridge 201 to ensure the quality uniformity and appearance quality of the elastic rubber layer 2, and at the same time, the annular ridge 201 structure is set on the extrusion mold, so that the outer surface of the elastic rubber layer 2 forms an annular ridge 201 with a height of 1mm-2mm and an adjacent spacing of 3mm-5mm, and then the metal substrate 1 coated with the rubber layer is placed in a vulcanization device, and vulcanized at 150°C-170°C for 30 minutes-600 minutes, and the pressure is 10MPa-15MPa, so that the elastic rubber layer 2 is tightly combined with the metal substrate 1;

[0054] The fabric reinforcement layer 3 is made to fit the surface of the elastic rubber layer 2. Aramid fiber and glass fiber are blended into filament fiber according to a mass ratio of 4:6. The fiber length is between 10 mm and 20 mm. The warp and weft density is 100 strands / inch to 150 strands / inch. The blended fiber fabric is then treated with a silane coupling agent for 10 minutes to 20 minutes at a temperature of 80°C to 100°C. The silane coupling agent can improve the chemical activity of the fiber surface and enhance the bonding strength with the rubber layer. After the treatment, the fabric is bonded to the outer side of the vulcanized elastic rubber layer 2 through a glue coating process. The glue coating amount is 80 g / m 2 -120g / m 2 The glue used in the gluing process is a special glue for rubber, and the rolling process is used to ensure the tightness of the bonding between the fabric reinforcement layer 3 and the elastic rubber layer 2, and to exclude air and gaps so that the two form a good composite structure. After bonding, a layer of waterproof and breathable membrane 4 is formed on the outer surface of the fabric reinforcement layer 3 by spraying to protect the internal structure from moisture erosion and maintain gas exchange;

[0055] The wear-resistant protective layer 5 is formed and fixed. After polytetrafluoroethylene and ultra-high molecular weight polyethylene are mixed in a mass ratio of 1:4, the mixed material is formed into a wear-resistant protective layer 5 with a thickness of 2mm-3mm by injection molding. The injection molding speed of the injection molding process is 20cm 3 / s-30cm 3 / s, the holding time is 10 seconds to 20 seconds, and the molding quality and dimensional accuracy of the wear-resistant protective layer 5 are guaranteed by accurately controlling the injection molding parameters. A diamond grid-like micro-texture structure 501 is set on the injection mold, and the grid side length is 0.5mm-1mm. Then, the molded wear-resistant protective layer 5 is attached to the outer side of the fabric reinforcement layer 3 through a hot pressing process. The hot pressing temperature is 180℃-200℃, the hot pressing pressure is 8MPa-12MPa, and the hot pressing time is 20 seconds to 40 seconds. The hot pressing process makes the wear-resistant protective layer 5 and the fabric reinforcement layer 3 firmly combined to form a complete composite bushing for automobiles.

[0056] Embodiment 2:

[0057] See also Figure 1-6 The present invention provides a technical solution: a composite bushing for automobiles and a manufacturing method thereof, wherein a titanium alloy raw material of suitable specifications is selected and forged according to a forging ratio of 5 to obtain a preliminarily formed metal substrate 1 blank; then a high-precision CNC lathe is used to set the cutting speed to 80m / min, the feed rate to 0.1mm / r, and the cutting depth to 0.5mm to process a cylindrical metal substrate 1, and a spiral groove 101 with a depth of 0.5mm is processed on the outer surface; a high molecular polymer damping material is filled into the spiral groove 101, and then connecting ears 102 are processed at both ends of the metal substrate 1, and a connecting hole 103 with a diameter of 8mm is drilled, and finally a thread strengthening coating with a thickness of 0.05mm is formed on the inner wall of the connecting hole 103 by an electroplating process;

[0058] 30 kg of silicone rubber and 70 kg of polyurethane rubber were weighed and put into an internal mixer, 3 kg of conductive carbon fiber with a diameter of 5 μm was added, and the mixture was mixed at 100° C. and a rotor speed of 40 rpm for 20 minutes; after mixing evenly, the rubber material was coated on the metal substrate 1 through an extruder at an extrusion speed of 20 mm / s to form an elastic rubber layer 2 with a thickness of 4 mm, and the outer surface of the elastic rubber layer 2 was formed with an annular convex ridge 201 with a height of 1 mm and an adjacent spacing of 3 mm by an extrusion die; the metal substrate 1 coated with the rubber layer was put into a vulcanization device, and vulcanized at 150° C. for 30 minutes at a pressure of 10 MPa;

[0059] Aramid fiber and glass fiber were blended into filament fiber in a mass ratio of 4:6, with a fiber length of 10 mm and a warp and weft density of 100 strands / inch; the blended fiber fabric was treated with a silane coupling agent at 80°C for 10 minutes, and then a special rubber glue was used at a temperature of 80 g / m 2 The fabric is laminated to the outside of the elastic rubber layer 2 by a coating amount of glue, and the tightness of the laminate is ensured by a rolling process, and finally a waterproof and breathable membrane 4 is sprayed on the outer surface of the fabric reinforcement layer 3;

[0060] After polytetrafluoroethylene and ultra-high molecular weight polyethylene were blended in a mass ratio of 1:4, the mixture was injected into the mixture with a 20 cm3 The blended material is molded into a wear-resistant protective layer 5 with a thickness of 2 mm at an injection molding speed of 10 seconds and a holding time of 10 seconds. The injection mold forms a diamond grid-like micro-texture structure 501 on the outer surface of the wear-resistant protective layer 5, and the grid side length is 0.5 mm. The molded wear-resistant protective layer 5 is bonded to the outer side of the fabric reinforcement layer 3 by a hot pressing process. The hot pressing temperature is 180°C, the hot pressing pressure is 8 MPa, and the hot pressing time is 20 seconds.

[0061] Embodiment three:

[0062] See also Figure 1-6 The present invention provides a technical solution: a composite bushing for automobiles and a manufacturing method thereof, wherein titanium alloy raw materials are selected, the forging ratio is 8, and after forging, a CNC machining center is used to set the cutting speed to 120m / min, the feed rate to 0.2mm / r, and the cutting depth to 1mm, to machine a cylindrical metal substrate 1, and a spiral groove 101 with a depth of 1.5mm is machined on the outer surface; after filling with a high molecular polymer damping material, connecting ears 102 are machined at both ends of the metal substrate 1 and a connecting hole 103 with a diameter of 10mm is drilled, and a thread strengthening coating is formed by electroplating, and the thickness is 0.1mm;

[0063] 30 kg of silicone rubber, 70 kg of polyurethane rubber and 5 kg of conductive carbon fiber with a diameter of 10 μm were weighed and put into an internal mixer, and mixed at 120° C. and a rotor speed of 60 rpm for 30 minutes; an elastic rubber layer 2 with a thickness of 6 mm was formed on a metal substrate 1 through an extruder at an extrusion speed of 30 mm / s, and the annular ridges 201 had a height of 2 mm and an adjacent spacing of 5 mm; vulcanization was performed at 170° C. for 60 minutes and a pressure of 15 MPa;

[0064] Aramid fiber and glass fiber are blended into filament fiber with a length of 20 mm and a warp and weft density of 150 strands / inch; treated with silane coupling agent at 100°C for 20 minutes and glued with rubber special glue at 120g / m 2 The amount of glue applied is attached to the outside of the elastic rubber layer 2 to form a fabric reinforcement layer 3, which is rolled to ensure tightness and sprayed with a waterproof breathable membrane 4;

[0065] After polytetrafluoroethylene and ultra-high molecular weight polyethylene are blended, the injection molding machine is 3 / s injection speed, 20 seconds holding time to form a wear-resistant protective layer 5 with a thickness of 3mm, and a grid side length of the micro-texture structure 501 of 1mm; hot pressing process parameters are 200°C, 12MPa, 40 seconds, and the wear-resistant protective layer 5 is attached to the outer side of the fabric reinforcement layer 3;

[0066] By comparison Figure 5The composite bushings for automobiles manufactured in Example 2 and Example 3 were subjected to performance test. The results showed that in terms of tensile strength (MPa), the tensile strength of Example 2 was 390 MPa, and that of Example 3 was 410 MPa. The tensile strength reflects the ability of the bushing to resist deformation and fracture when subjected to axial tension. The forging ratio of the metal matrix 1 in Example 3 was 8, which was 5 compared with that of Example 2, and could make the internal structure of the titanium alloy more compact and uniform, providing a better strength foundation for the whole. At the same time, the content of conductive carbon fiber filaments in the rubber layer in Example 3 reached 5 kg (diameter 10 μm). The relatively large amount of carbon fiber filaments played a certain reinforcing role in the rubber matrix, and synergistically improved the overall tensile strength.

[0067] In the compression modulus (MPa), the compression modulus of Example 2 is 1650 MPa, and that of Example 3 is 1750 MPa; the compression modulus reflects the ability of a material to resist elastic deformation under a compressive load, and a higher value indicates a smaller deformation under the same compressive force;

[0068] In the damping efficiency (%), the damping efficiency of Example 2 reaches 88%, and that of Example 3 is 86%. The damping efficiency indicates the ability of the bushing to absorb and dissipate vibration energy. The higher the value, the better the damping effect. The damping mainly depends on the elastic rubber layer 2 and the high molecular polymer damping material filled in the spiral groove 101 of the metal matrix 1. The mixing conditions (mixing at 100°C and 40rpm rotor speed for 20 minutes) and the vulcanization conditions (vulcanization at 150°C for 30 minutes) of the rubber layer in Example 2 may make the internal microstructure of the rubber more conducive to energy absorption and dissipation, for example, the arrangement and cross-linking degree of the rubber molecular chains are more suitable for damping. In addition, the filling effect of the damping material in the spiral groove 101 and the synergistic effect with the rubber layer in Example 2 may perform better in this test, which comprehensively leads to a slightly higher damping efficiency than that of Example 2.

[0069] In the wear resistance performance (wear amount, mg / 1000 cycles), the wear amount of Example 2 is 7 mg / 1000 cycles, and that of Example 3 is 6 mg / 1000 cycles. This index directly reflects the wear resistance of the bushing during the friction process. The smaller the wear amount, the better the wear resistance. The injection molding process parameters of the wear-resistant protective layer 5 in Example 3 (injection molding speed 30 cm 3 / s, holding time 20 seconds) and hot pressing process parameters (hot pressing temperature 200°C, hot pressing pressure 12MPa, hot pressing time 40 seconds) may make the polytetrafluoroethylene and ultra-high molecular weight polyethylene blend material form a denser and more uniform structure during the molding process, and the diamond grid-like micro-texture structure 501 (grid side length 1mm) on its outer surface may have better wear resistance and anti-wear stability in Example 3, thereby effectively reducing the wear amount;

[0070] In the antistatic performance (surface resistance, Ω), the surface resistance of Example 2 is 6×10^6Ω, and that of Example 3 is 7×10^7Ω. The lower the surface resistance value, the better the conductive performance of the material, which is more conducive to the dissipation of static electricity. The antistatic performance is mainly determined by the conductive carbon fiber filaments in the elastic rubber layer 2. The diameter of the carbon fiber filaments in Example 2 is 5μm and the content is 3kg. Compared with Example 3, the distribution density and the conductive network construction in the rubber layer are different, so that Example 2 can form a more effective conductive path, thereby having a lower surface resistance and better antistatic performance.

[0071] In the temperature resistance range (℃), both embodiments can maintain no obvious performance change in the range of -40-120℃, which shows that the composite bushing has good stability in the designed temperature resistance range, which is due to the selection of materials of each layer and the design of the composite structure. The titanium alloy of the metal matrix 1 has good temperature resistance, and the elastic rubber layer 2 adopts a blend of silicone rubber and polyurethane rubber. The silicone rubber itself is resistant to high temperature and aging. After the two are blended, they can maintain stable performance in a wide temperature range. The materials and processes of the fabric reinforcement layer 3 and the wear-resistant protective layer 5 also ensure that there will be no structural damage or significant performance degradation due to temperature changes in this temperature range. The good combination between the layers further ensures the ability of the overall structure to work together at different temperatures;

[0072] In fatigue life (number of cycles), the fatigue life of Example 2 is 1.6×10^6 cycles, and that of Example 3 is 1.8×10^6 cycles. Fatigue life reflects the number of cycles that the bushing can withstand under the cyclic stress of repeated loading and unloading, and is an important indicator for measuring the durability of the bushing. After the metal substrate 1 in Example 3 is forged with a forging ratio of 8 and a specific machining process, it has fewer internal defects, a more uniform and stable structure, and can better withstand cyclic stress. At the same time, the bonding strength and synergy between the layers also play a key role in the fatigue process.

[0073] In the tear strength (kN / m), the tear strength of Example 2 is 130kN / m, and that of Example 3 is 140kN / m. The tear strength indicates the ability of a material to resist tearing damage, which is essential for the bushing to maintain structural integrity under complex stress conditions. The fabric reinforcement layer 3 is a blend of aramid fiber and glass fiber, and the fiber characteristics, blending ratio, warp and weft density, and the combination with the rubber layer have a significant effect on the tear strength. In Example 3, the fiber length is 20mm, the warp and weft density is 150 strands / inch, and the fiber structure is tighter than that of Example 2. In addition, the fiber is treated with a silane coupling agent (treated at 100°C for 20 minutes) and the glue coating process (rubber-specific glue, the glue coating amount is 120g / m 2 ) After the rubber layer is bonded more firmly, it can more effectively prevent the expansion of tear cracks, thereby improving the tear resistance;

[0074] In terms of waterproof performance (penetration pressure, MPa), the waterproof penetration pressure of Example 2 is 0.6 MPa, and that of Example 3 is 0.7 MPa. This index measures the ability of the bushing to prevent water penetration. The higher the penetration pressure, the better the waterproof performance.

[0075] In the bonding strength with adjacent components (MPa), the bonding strength with adjacent components of Example 2 is 9MPa, and that of Example 3 is 10MPa. The bonding strength affects the reliability and stability of the connection between the bushing and other parts of the automobile. During the operation of the automobile, good bonding strength can ensure the effective transmission of force and the coordinated work of the overall structure.

[0076] And in Figure 6 It can be seen from the comparison between the bushing of the present invention and the traditional metal bushing and the traditional rubber bushing that in terms of fatigue life, although the composite bushing is slightly inferior to the metal bushing, it is much better than the rubber bushing and can maintain good performance stability during long-term use. In terms of tear resistance, it is between metal and rubber bushings, which can effectively prevent tearing damage under complex stress conditions. The waterproof performance is significantly improved compared with the rubber bushing due to the waterproof and breathable membrane 4 outside the fabric reinforcement layer 3. Although it is not as good as the metal bushing, it can meet the requirements of most automotive working conditions. In terms of bonding strength with adjacent components, through special connection process treatment, its bonding strength can ensure that the various layers of structure work together under working conditions such as automobile running vibration and reliable connection with external components. Compared with rubber bushings, it has certain advantages, while metal bushings mainly rely on mechanical connection methods and do not have the comparative significance of this bonding strength index. These data further reflect the characteristics of comprehensive optimization of composite bushings in multiple aspects of performance, making it more adaptable and competitive in automotive application scenarios.

[0077] Therefore, the composite bushing has excellent performance in strength, shock absorption, wear resistance, antistatic performance and corrosion resistance, etc., and can meet the use requirements of automobiles under various complex working conditions, and effectively improve the overall performance, comfort and safety of the automobile.

[0078] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the technical solution of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A composite bushing for automobile, characterized in that: It comprises a metal substrate (1), the outer surface of the metal substrate (1) is provided with an elastic rubber layer (2), the outer side of the elastic rubber layer (2) is provided with a fabric reinforcement layer (3), the outer surface of the fabric reinforcement layer (3) is provided with a waterproof breathable membrane (4), and the outer surface of the waterproof breathable membrane (4) is provided with a wear-resistant protective layer (5); The metal substrate (1) is made of titanium alloy, the metal substrate (1) is in a cylindrical structure, a spiral groove (101) is provided on the outer surface of the metal substrate (1) along the axial direction, the spiral groove (101) is filled with a shock-absorbing damping material, and connecting ears (102) extending outward are provided at both ends of the metal substrate (1), a plurality of connecting holes (103) are evenly provided on the connecting ears (102), and the inner wall of the connecting hole (103) has a thread strengthening coating to enhance the reliability of the connection; The elastic rubber layer (2) is coated on the outer surface of the metal substrate (1), the elastic rubber layer (2) is made of a blend of silicone rubber and polyurethane rubber, wherein the mass ratio of silicone rubber to polyurethane rubber is 3:7, the outer surface of the elastic rubber layer (2) has a plurality of equally spaced annular ridges (201), and conductive carbon fiber filaments are evenly dispersed in the elastic rubber layer (2), the mass fraction of the conductive carbon fiber filaments accounting for 3% to 5% of the total mass of the rubber layer, for dissipating static electricity; The fabric reinforcement layer (3) is attached to the outer surface of the elastic rubber layer (2), the fabric reinforcement layer (3) is made of a blend of aramid fiber and glass fiber, the mass ratio of aramid fiber to glass fiber is 4:6, and the fabric reinforcement layer (3) is treated with a special silane coupling agent to improve the bonding force with the rubber layer, and the outer surface of the fabric reinforcement layer (3) is coated with a waterproof and breathable membrane (4), and the waterproof and breathable membrane (4) is used to prevent moisture intrusion and ensure gas exchange; The wear-resistant protective layer (5) is wrapped around the outer surface of the waterproof breathable membrane (4), and the wear-resistant protective layer (5) is made of a blend of polytetrafluoroethylene and ultra-high molecular weight polyethylene, wherein the mass ratio of polytetrafluoroethylene to ultra-high molecular weight polyethylene in the blend is 1:4, and the outer surface of the wear-resistant protective layer (5) has a micro-texture structure (501), and the micro-texture structure is a diamond grid shape, so as to improve the anti-slip performance and wear resistance.

2. The composite bushing for automobile according to claim 1, characterized in that: The shock-absorbing and damping material filled in the spiral groove (101) is a high molecular polymer damping material, the loss factor of which is between 0.5 and 0.8, and can maintain stable damping performance within a temperature range of -40°C to 120°C.

3. The composite bushing for automobile according to claim 1, characterized in that: The elastic rubber layer (2) and the metal substrate (1) are tightly bonded together through a vulcanization process, the vulcanization temperature is 150° C.-170° C., the vulcanization time is 30 minutes-60 minutes, and the pressure is 10 MPa-15 MPa.

4. The composite bushing for automobile according to claim 1, characterized in that: The aramid fibers and glass fibers of the fabric reinforcement layer (3) are both filament fibers, and the fibers are interwoven with each other to form a stable mesh structure.

5. The composite bushing for automobile according to claim 1, characterized in that: The wear-resistant protective layer (5) and the fabric reinforcement layer (3) are bonded by a hot pressing process, the hot pressing temperature is 180° C.-200° C., the hot pressing pressure is 8 MPa-12 MPa, and the hot pressing time is 20 seconds-40 seconds.

6. A method for manufacturing a composite bushing for an automobile, characterized in that: The following steps are involved: S1: Processing the metal substrate (1), firstly, the titanium alloy raw material is forged and machined into a cylindrical metal substrate (1) blank, then a spiral groove (101) with a depth of 0.5 mm to 1.5 mm is processed on the outer surface of the metal substrate (1) blank by CNC processing equipment, then a high molecular polymer damping material is filled in the spiral groove (101), and then both ends of the metal substrate (1) are processed to form a connecting ear (102) extending outward, and a plurality of connecting holes (103) are drilled on the connecting ear (102), and finally a thread strengthening coating is formed on the inner wall of the connecting hole (103) by electroplating; S2: forming the elastic rubber layer (2), blending silicone rubber and polyurethane rubber in a mass ratio of 3:7, adding conductive carbon fiber filaments with a diameter of 5 μm-10 μm and a mass fraction of 3%-5% of the total mass of the rubber layer, kneading in an internal mixer at 100° C.-120° C. for 20 minutes-30 minutes, and after kneading evenly, coating the rubber material on the processed metal substrate (1) through an extrusion process to form an elastic rubber layer (2) with a thickness of 4 mm-6 mm, and at the same time, providing an annular ridge (201) structure on the extrusion die, so that the outer surface of the elastic rubber layer (2) forms an annular ridge (201) with a height of 1 mm-2 mm and an adjacent spacing of 3 mm-5 mm, and then placing the metal substrate (1) coated with the rubber layer in a vulcanization device, and vulcanizing at 150° C.-170° C. for 30 minutes-60 minutes, and a pressure of 10 MPa-15 MPa; S3: The fabric reinforcement layer (3) is laminated on the surface of the elastic rubber layer (2), and aramid fiber and glass fiber are blended into filament fiber in a mass ratio of 4:6, with the fiber length being between 10 mm and 20 mm and the warp and weft density being between 100 strands / inch and 150 strands / inch. The blended fiber fabric is then treated with a silane coupling agent, and after the treatment, the fabric is laminated on the outer side of the vulcanized elastic rubber layer (2) by a glue coating process, with the glue coating amount being 80 g / m 2 -120g / m 2 After lamination, a layer of waterproof and breathable membrane (4) is formed on the outer surface of the fabric reinforcement layer (3) by a spraying process; S4: forming the wear-resistant protective layer (5), after polytetrafluoroethylene and ultra-high molecular weight polyethylene are blended in a mass ratio of 1:4, the blended material is formed into a wear-resistant protective layer (5) with a thickness of 2mm-3mm by an injection molding process, a diamond grid-like micro-texture structure (501) is arranged on the injection mold, and the grid side length is 0.5mm-1mm. Then, the formed wear-resistant protective layer (5) is attached to the outer side of the fabric reinforcement layer (3) by a hot pressing process, the hot pressing temperature is 180°C-200°C, the hot pressing pressure is 8MPa-12MPa, and the hot pressing time is 20 seconds-40 seconds.

7. The composite bushing for automobile and the method for manufacturing the same according to claim 6, characterized in that: In S1, the forging ratio of the forging process is controlled at 5-8, and the cutting parameters of the machining process are set according to the dimensional accuracy requirements of the metal substrate (1) to ensure the machining accuracy and surface quality of the metal substrate (1).

8. The composite bushing for automobile and the method for manufacturing the same according to claim 6, characterized in that: In S2, the rotor speed of the internal mixer is controlled at 40 rpm-60 rpm, and the extrusion speed of the extrusion process is adjusted according to the thickness of the rubber layer and the molding requirements of the annular ridge (201) to ensure the quality uniformity and appearance quality of the elastic rubber layer (2).

9. The composite bushing for automobile and the method for manufacturing the same according to claim 6, characterized in that: In S3, the treatment time of the silane coupling agent is 10 minutes to 20 minutes, the treatment temperature is 80°C to 100°C, the glue used in the gluing process is a special glue for rubber, and during the bonding process, a rolling process is used to ensure the tightness of the bonding between the fabric reinforcement layer (3) and the elastic rubber layer (2).

10. The composite bushing for automobile and the manufacturing method thereof according to claim 6, characterized in that: In S4, the injection molding process has an injection speed of 20cm 3 / s-30cm 3 / s, the holding time is 10 seconds to 20 seconds, the heating rate of the hot pressing process is 10°C / s to 20°C / s, and the cooling rate is 8°C / s to 15°C / s, so as to ensure the molding quality of the wear-resistant protective layer (5) and the bonding effect with the fabric reinforcement layer (3).

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