A processing method for a metal-polymer composite self-lubricating bearing material

Abstract

This invention discloses a processing method for a metal-polymer composite self-lubricating bearing material, comprising six steps: pre-processing, metal matrix pretreatment, polymer lubrication layer preparation and composite molding, post-processing, performance testing and quality control, and packaging and storage. This invention solves the problems of poor product consistency, low pass rate, insufficient bonding force, and numerous molding defects in existing processing methods. It achieves standardized processing procedures and precise parameters, taking into account both the mechanical and lubrication properties of the material, adapting to the needs of mass production, and improving product quality and production economy.

Description

Technical Field

[0001] This invention relates to the field of bearing material processing methods, specifically to a processing method for a metal-polymer composite self-lubricating bearing material. Background Technology

[0002] Self-lubricating bearings are widely used in low-to-medium speed and light-to-medium load applications due to their advantages such as no need for additional lubricant, convenient maintenance, and wide applicability. Metal-polymer composite self-lubricating bearings adopt a structure of "metal matrix bearing + polymer coating self-lubrication," combining the high strength and toughness of metal materials with the excellent self-lubricating and wear-resistant properties of polymer materials, and are currently one of the mainstream types of self-lubricating bearings.

[0003] Existing processing methods for metal-polymer composite self-lubricating bearing materials suffer from problems such as non-standardized processing procedures, inaccurate parameter control, and unreasonable connections between various stages. This leads to poor product consistency and low yield rates. Specifically, the adhesion between the metal substrate and the polymer coating is insufficient, making delamination likely; bubbles and cracks are easily generated during the polymer lubrication layer molding process, affecting self-lubricating performance and service life; and the lack of unified standards for raw material handling and equipment operation results in high energy consumption, low efficiency, and difficulty in achieving stable mass production. To address these technical pain points, there is an urgent need for a processing method for metal-polymer composite self-lubricating bearing materials that is complete in process, has clear parameters, is suitable for mass production, and can guarantee product quality. Summary of the Invention

[0004] This invention aims to provide a processing method for metal-polymer composite self-lubricating bearing materials, solving problems such as poor product consistency, low pass rate, insufficient bonding force, and numerous molding defects in existing processing methods. It achieves standardized processing procedures and precise parameters, taking into account both the mechanical and lubrication properties of the material, adapting to the needs of mass production, and improving product quality and production economy.

[0005] To address the aforementioned technical problems, this invention provides six steps: pre-processing preparation, metal substrate pretreatment, polymer lubricant layer preparation and composite molding, post-processing, performance testing and quality control, and packaging and storage. The specific operations are as follows: (1) Preparation before processing: ① Raw material selection and proportioning: The metal matrix is ​​made of low-carbon steel, copper alloy or aluminum alloy, with a thickness of 2-8mm; the polymer lubricating layer is based on PTFE, PI or PEEK, with 5%-15% solid lubricant, 10%-20% reinforcing agent and 3%-8% binder added, and the polymer raw materials are dried to a moisture content of ≤0.5%; auxiliary raw materials include degreasing agent, surface treatment agent, mold release agent and cleaning agent; the mixing uniformity of the polymer lubricating layer is ≥95%, and the thickness ratio of the metal matrix to the polymer lubricating layer is 5:1-10:1; ② Equipment and tool preparation: Equip with pretreatment equipment, composite molding equipment, post-processing equipment, testing equipment and auxiliary tools; ③Environmental preparation: The processing environment temperature is 15-25℃, the relative humidity is ≤60%, the environment is clean and well-ventilated, and operators wear protective equipment; (2) Pretreatment of the metal matrix: ① Cutting and rough machining: Cut the metal raw materials and perform rough machining, leaving a finishing allowance of 0.1-0.3mm, and the dimensional deviation of the blank is ≤±0.05mm; ② Degreasing treatment: Add degreasing agent to the ultrasonic cleaner, clean at 40-60℃ for 10-15 minutes, and rinse with deionized water 2-3 times; ③ Surface roughening treatment: Sandblasting or grinding is used. After sandblasting, the surface roughness Ra reaches 1.6-3.2μm; ④ Surface activation treatment: Plasma surface treatment or silane coupling agent treatment is used; ⑤ Inspection after pretreatment: The surface is qualified if there is no oxide layer, no oil stains, and the roughness meets the standard; (3) Preparation and composite molding of polymer lubricating layer: ① Raw material mixing: Weigh the raw materials according to the ratio, stir evenly, and dry at 80-100℃ for 20-30 minutes; ② Composite molding: Select hot pressing, injection molding or roll forming. In hot pressing, the mold is preheated and then loaded. The pressure is slowly increased to the preset pressure, kept at a constant temperature and then naturally cooled and demolded. (4) Post-processing: ① Finishing: Finishing to the required dimensions, with a dimensional deviation of ≤ ±0.01mm; ② Surface polishing: Polish with 200-400 grit abrasive wheel, surface roughness Ra≤0.8μm; ③ Aging treatment: Keep at 80-150℃ for 2-4 hours, then allow to cool naturally; ④ Cleaning and drying: Cleaned with ultrasonic deionized water and then dried; ⑤ Post-processing inspection: Inspect dimensions, roughness, and surface quality; (5) Performance testing and quality control: ① The testing items include bonding strength, mechanical properties, self-lubricating properties, dimensions and appearance, and temperature resistance (high-temperature conditions). The bonding strength is ≥10MPa, the coefficient of friction is ≤0.15, and the wear is ≤0.01mm. 3 / (N·m); ② The sampling ratio for each batch is ≥5%. Unqualified batches are re-inspected. If they still fail the re-inspection, they are scrapped. A processing ledger is established. (6) Packaging and storage: ① Waterproof and shockproof packaging with relevant product information clearly marked; ② Store in a dry, well-ventilated warehouse at 10-25℃ and relative humidity ≤60%.

[0006] Further, in step (1) ①, the low-carbon steel conforms to GB / T700 standard, the copper alloy conforms to GB / T2040 standard, and the aluminum alloy conforms to GB / T3190 standard; the solid lubricant is graphite, molybdenum disulfide or boron nitride, the reinforcing agent is glass fiber or carbon fiber, the binder is epoxy resin or phenolic resin; the degreasing agent is ethanol, acetone or special metal degreasing agent, the surface treatment agent is silane coupling agent KH-550 or titanate coupling agent, and the release agent is silicone oil or polytetrafluoroethylene emulsion.

[0007] Further, in step (1) ②, the pretreatment equipment includes a metal grinding machine with a grinding wheel grit size of 80-120 mesh; an ultrasonic cleaner with a power of 500-800W and a frequency of 40kHz; a drying oven with a temperature control range of 50-200℃ and an accuracy of ±2℃; a plasma surface treatment machine with an output power of 1-3kW; and a sandblasting device with a quartz sand grit size of 40-80 mesh. The composite molding equipment includes a hot press molding machine with a pressure range of 0.5-5MPa, a temperature control range of room temperature to 300℃, and an accuracy of ±1℃; an injection molding machine with an injection pressure of 10-30MPa and a barrel temperature of 180-380℃; and a roller press with a pressure of 0.3-1MPa and a speed of 5-15r / min.

[0008] Furthermore, in step (2) ③, the sandblasting process uses quartz sand as the medium, the sandblasting pressure is 0.2-0.4MPa, the sandblasting distance is 100-150mm, the sandblasting angle is 45°-60°, and the sandblasting time is 3-5min; the grinding uses an 80-120 mesh grinding wheel.

[0009] Further, in step (2) ④, the plasma surface treatment uses argon gas with a purity of ≥99.99%, a treatment power of 1.5-2kW, and a treatment time of 2-3min; the silane coupling agent treatment uses a KH-550 solution with a mass fraction of 1%-2%, a soaking time of 5-10min, and drying at 80-100℃ for 10-15min.

[0010] Further, in step (3) ②, the pretreatment of the hot-pressing mold includes cleaning and degreasing, applying release agent, and preheating. The preheating temperature is PTFE: 180-200℃, PI: 250-280℃, PEEK: 300-320℃, and the preheating time is 15-20min. The pressurization rate is 0.1MPa / min, and the preset pressure is PTFE: 1-2MPa, PI: 2-3MPa, PEEK: 3-5MPa. The constant temperature is PTFE: 190℃, PI: 260℃, PEEK: 310℃. The cooling rate is ≤5℃ / min, and the depressurization rate is 0.05MPa / min.

[0011] Furthermore, in step (4) ①, the roundness of the bearing sleeve part is ≤0.01mm and the parallelism of the end face is ≤0.02mm; in step (4) ②, the polishing speed is 1000-1500r / min and the polishing time is 5-10min.

[0012] Furthermore, in step (5) ①, the mechanical performance testing requirements are as follows: the hardness of the low carbon steel matrix is ​​≥120HB, the hardness of the brass matrix is ​​≥80HB, and the hardness of the aluminum alloy matrix is ​​≥60HB; the tensile strength of the composite material is ≥200MPa, and the elongation at break is ≥5%; in the temperature resistance test, the PI bearing is ≤260℃, the PEEK bearing is ≤250℃, the PTFE bearing is ≤200℃, and there is no deformation or crack after 24h of heat preservation.

[0013] Furthermore, in step (6) ①, individual bearings are wrapped in plastic film and placed in batches into foam boxes or cartons with desiccant inside; the packaging is labeled with the product name, specifications, batch number, production date, and shelf life.

[0014] Furthermore, it also includes precautions: the moisture content of the polymer raw material should be ≤0.5%; the interval between pretreatment of the metal matrix and composite molding should not exceed 2 hours; the molding parameters should be adjusted strictly according to the type of polymer; the equipment should be maintained and the testing equipment calibrated regularly; if the blank or finished product is unqualified, the cause should be analyzed and it should be reprocessed.

[0015] The beneficial effects of this invention are: 1. Through standardized operation and precise parameter control throughout the entire process, the metal substrate and polymer coating are tightly bonded (bonding force ≥10MPa), the polymer lubrication layer is free of bubbles and cracks, and the product qualification rate is greatly improved.

[0016] 2. Achieving a perfect combination of the load-bearing capacity of the metal substrate and the self-lubricating properties of the polymer coating, with a friction coefficient ≤0.15 and wear ≤0.01mm. 3 / (N·m), suitable for medium and low speed and light to medium load conditions.

[0017] 3. The process is standardized and easy to operate, and the equipment selection is universal, which can realize the stable mass production of various bearings and improve production efficiency.

[0018] 4. By rationally proportioning raw materials and making efficient use of resources, we can reduce drug consumption, energy consumption, and scrap rate, while extending product life and improving production economy. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments, so that those skilled in the art can better understand and implement the present invention, but the embodiments are not intended to limit the present invention.

[0021] Furthermore, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0024] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0025] Example 1: Preparation of low-carbon steel-PTFE composite self-lubricating bearings by hot pressing composite molding 1. Preparation before processing: Raw materials: The metal matrix is ​​made of Q235 low carbon steel with a thickness of 4mm, conforming to GB / T700 standard; the polymer lubricating layer is made of PTFE as the base material (accounting for 70%), with the addition of 10% graphite (solid lubricant), 15% glass fiber (reinforcing agent), and 5% epoxy resin (binder), and the water content is 0.3% after drying treatment; the auxiliary raw materials are ethanol (degreasing agent), KH-550 silane coupling agent (surface treatment agent), silicone oil (release agent), and deionized water (cleaning agent). Equipment: Metal grinding machine (100 mesh abrasive wheel), ultrasonic cleaner (600W power, 40kHz frequency), drying oven (temperature control range 50-200℃, accuracy ±2℃), sandblasting equipment (60 mesh quartz sand), hot press molding machine (pressure 0.5-5MPa, temperature control chamber -300℃, accuracy ±1℃), lathe, milling machine, polishing machine (300 mesh abrasive wheel), aging furnace, hardness tester, friction and wear tester, adhesion tester, metallographic microscope, stirrer (speed 300-500r / min), custom Cr12MoV mold (roughness Ra≤0.8μm), gauges (accuracy ±0.01mm). Environment: Temperature 20℃, relative humidity 55%, clean and well-ventilated; operators wear gloves, masks, and goggles.

[0026] 2. Metal Substrate Pretreatment: Rough Cutting: Cut Q235 steel plates to the required dimensions, leaving a 0.2mm finishing allowance after rough cutting, with a dimensional deviation of ±0.03mm. Degreasing: Place in an ultrasonic cleaner, add a degreasing agent with an ethanol and deionized water volume ratio of 1:1, clean at 50℃ for 12 minutes, and rinse 3 times with deionized water. Surface Roughening: Sandblasting treatment, using quartz sand as the medium, sandblasting pressure 0.3MPa, distance 120mm, angle 50°, time 4 minutes, surface roughness Ra=2.4μm. Surface Activation: Immerse in 1.5% KH-550 silane coupling agent solution for 8 minutes, remove and dry at 80℃ for 12 minutes. Inspection: Metallographic microscopy reveals no oxide layer or oil stains; wiping with a white cloth leaves no stains, indicating it is qualified.

[0027] 3. Polymer lubricant layer preparation and hot-press composite molding: Raw material mixing: Weigh PTFE, graphite, glass fiber, and epoxy resin according to the formula, with a weighing accuracy of ±0.05g; stir at low speed (300r / min) for 5min, then at high speed (500r / min) for 12min, and dry at 90℃ for 25min after uniform mixing. Mold pretreatment: Clean and degrease, evenly apply silicone oil release agent (thickness 0.008mm), place in a hot press molding machine and preheat to 190℃ for 18min. Mold loading: Place the qualified metal substrate at the bottom of the mold, evenly spread the polymer raw material, and leave a 12% compression allowance. Hot pressing: Slowly increase the pressure to 1.5MPa (pressure increase rate 0.1MPa / min), and hold at a constant temperature of 190℃ for 35min. Cooling and demolding: Allow to cool naturally to room temperature (cooling rate 4℃ / min), slowly release the pressure (0.05MPa / min), remove the blank, and if there are no bubbles, cracks, or delamination, it is qualified.

[0028] 4. Post-processing: Finishing: Lathe and milling machine finishing to remove pre-reserved allowances, dimensional deviation ±0.01mm, roundness ±0.01mm, end face parallelism ±0.02mm. Surface polishing: 300-grit abrasive wheel polishing, speed 1200r / min, time 8min, surface roughness Ra=0.6μm, no scratches or burrs. Aging treatment: 100℃ for 3h, naturally cooled to room temperature. Cleaning and drying: Ultrasonic deionized water cleaning for 8min, drying at 70℃ for 12min. Inspection: Dimensions and roughness meet standards, surface is free of defects, qualified.

[0029] 5. Performance testing and quality control: Adhesion strength test: Adhesion strength 12MPa, meets requirements. Mechanical property test: Q235 matrix hardness 125HB, composite material tensile strength 210MPa, elongation at break 6%, meets requirements. Self-lubricating performance test: Load 100N, rotation speed 200r / min, time 3h, friction coefficient 0.12, wear amount 0.008mm. 3 / (N·m), meets requirements. Dimensional and appearance inspection: both meet design requirements, qualified. Sampling ratio: 6%, inspection passed, processing log established.

[0030] 6. Packaging and Storage: Each bearing is individually wrapped in plastic film, then placed in bulk into foam boxes with desiccant inside and relevant information labeled; stored in a warehouse at 20℃ and 55% relative humidity, shelf life is 12 months.

[0031] Example 2: Preparation of Brass-PEEK Composite Self-Lubricating Bearing by Injection Molding 1. Preparation before processing: The metal substrate is H62 brass with a thickness of 6mm, conforming to GB / T2040 standard; the polymer lubricating layer is made of PEEK as the base material (accounting for 65%), with the addition of 12% molybdenum disulfide, 18% carbon fiber, and 5% phenolic resin, and the moisture content after drying is 0.4%; the equipment used is an injection molding machine (injection pressure 10-30MPa, barrel temperature 180-380℃) and other related equipment in Example 1; the ambient temperature is 22℃ and the relative humidity is 58%.

[0032] 2. Metal substrate pretreatment: After rough cutting, leave a 0.3mm allowance, degrease treatment (special degreaser, 55℃ cleaning for 10min), sandblasting treatment (pressure 0.4MPa, time 5min, Ra=3.0μm), plasma surface treatment (argon purity 99.99%, power 2kW, time 3min), and pass inspection.

[0033] 3. Preparation of polymer lubricating layer and injection molding composite molding: After mixing the raw materials, dry them at 85℃ for 30 min; the barrel temperature of the injection molding machine is 320℃, the injection pressure is 20MPa, and the polymer raw materials are injected into the mold containing the metal matrix. After cooling, the mold is demolded and the blank is qualified.

[0034] 4. Post-processing: finishing, polishing (400-grit grinding wheel), aging treatment (120℃ for 2.5 hours), cleaning and drying, and inspection.

[0035] 5. Performance Testing: Bonding strength 13MPa, brass matrix hardness 85HB, tensile strength 220MPa, coefficient of friction 0.13, wear amount 0.007mm 3 / (N·m), all indicators meet the requirements; sampling ratio 5%, qualified.

[0036] 6. Packaging and storage: Pack according to standard packaging and store in a qualified warehouse.

[0037] Reference proportions (traditional processing methods) Using traditional processing methods, the following issues were identified: inaccurate raw material proportioning (polymer mixing uniformity of 85%), incomplete pretreatment of the metal substrate (no activation treatment), non-standard hot pressing parameters (excessive temperature and rapid pressure increase), and lack of rigorous quality inspection. The results showed that the product's adhesion was only 6 MPa, prone to delamination, and the polymer coating exhibited bubbles and cracks. The coefficient of friction was 0.20, and the wear was 0.015 mm. 3 / (N·m), the product qualification rate is only 70%, and the overall production cost is 25% higher than that of this invention.

[0038] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A method for processing a metal-polymer composite self-lubricating bearing material, characterized in that, The process includes six stages: pre-processing, metal substrate pretreatment, polymer lubricant layer preparation and composite molding, post-processing, performance testing and quality control, and packaging and storage. The specific operations are as follows: (1) Preparation before processing: ① Raw material selection and proportioning: The metal matrix is ​​made of low-carbon steel, copper alloy or aluminum alloy, with a thickness of 2-8mm; the polymer lubricating layer is based on PTFE, PI or PEEK, with 5%-15% solid lubricant, 10%-20% reinforcing agent and 3%-8% binder added, and the polymer raw materials are dried to a moisture content of ≤0.5%; auxiliary raw materials include degreasing agent, surface treatment agent, mold release agent and cleaning agent; the mixing uniformity of the polymer lubricating layer is ≥95%, and the thickness ratio of the metal matrix to the polymer lubricating layer is 5:1-10:1; ② Equipment and tool preparation: Equip with pretreatment equipment, composite molding equipment, post-processing equipment, testing equipment and auxiliary tools; ③Environmental preparation: The processing environment temperature is 15-25℃, the relative humidity is ≤60%, the environment is clean and well-ventilated, and operators wear protective equipment; (2) Pretreatment of the metal matrix: ① Cutting and rough machining: Cut the metal raw materials and perform rough machining, leaving a finishing allowance of 0.1-0.3mm, and the dimensional deviation of the blank is ≤±0.05mm; ② Degreasing treatment: Add degreasing agent to the ultrasonic cleaner, clean at 40-60℃ for 10-15 minutes, and rinse with deionized water 2-3 times; ③ Surface roughening treatment: Sandblasting or grinding is used. After sandblasting, the surface roughness Ra reaches 1.6-3.2μm; ④ Surface activation treatment: Plasma surface treatment or silane coupling agent treatment is used; ⑤ Inspection after pretreatment: The surface is qualified if there is no oxide layer, no oil stains, and the roughness meets the standard; (3) Preparation and composite molding of polymer lubricating layer: ① Raw material mixing: Weigh the raw materials according to the ratio, stir evenly, and dry at 80-100℃ for 20-30 minutes; ② Composite molding: Select hot pressing, injection molding or roll forming. In hot pressing, the mold is preheated and then loaded. The pressure is slowly increased to the preset pressure, kept at a constant temperature and then naturally cooled and demolded. (4) Post-processing: ① Finishing: Finishing to the required dimensions, with a dimensional deviation of ≤ ±0.01mm; ② Surface polishing: Polish with 200-400 grit abrasive wheel, surface roughness Ra≤0.8μm; ③ Aging treatment: Keep at 80-150℃ for 2-4 hours, then allow to cool naturally; ④ Cleaning and drying: Cleaned with ultrasonic deionized water and then dried; ⑤ Post-processing inspection: Inspect dimensions, roughness, and surface quality; (5) Performance testing and quality control: ① The testing items include bonding strength, mechanical properties, self-lubricating properties, dimensions and appearance, and temperature resistance (high-temperature conditions). The bonding strength is ≥10MPa, the coefficient of friction is ≤0.15, and the wear is ≤0.01mm. 3 / (N·m); ② The sampling ratio for each batch is ≥5%. Unqualified batches are re-inspected. If they still fail the re-inspection, they are scrapped. A processing ledger is established. (6) Packaging and storage: ① Waterproof and shockproof packaging with relevant product information clearly marked; ② Store in a dry, well-ventilated warehouse at 10-25℃ and relative humidity ≤60%.

2. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (1) ①, low carbon steel conforms to GB / T700 standard, copper alloy conforms to GB / T2040 standard, and aluminum alloy conforms to GB / T3190 standard; solid lubricant is graphite, molybdenum disulfide or boron nitride, reinforcing agent is glass fiber or carbon fiber, binder is epoxy resin or phenolic resin; degreasing agent is ethanol, acetone or special metal degreasing agent, surface treatment agent is silane coupling agent KH-550 or titanate coupling agent, and release agent is silicone oil or polytetrafluoroethylene emulsion.

3. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (1) ②, the pretreatment equipment includes a metal grinding machine with a grinding wheel grit size of 80-120 mesh; an ultrasonic cleaner with a power of 500-800W and a frequency of 40kHz; a drying oven with a temperature control range of 50-200℃ and an accuracy of ±2℃; a plasma surface treatment machine with an output power of 1-3kW; and a sandblasting device with a quartz sand grit size of 40-80 mesh. The composite molding equipment includes a hot press molding machine with a pressure range of 0.5-5MPa, a temperature control range of room temperature to 300℃, and an accuracy of ±1℃; an injection molding machine with an injection pressure of 10-30MPa and a barrel temperature of 180-380℃; and a roller press with a pressure of 0.3-1MPa and a speed of 5-15r / min.

4. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (2) ③, the sandblasting treatment uses quartz sand as the medium, the sandblasting pressure is 0.2-0.4MPa, the sandblasting distance is 100-150mm, the sandblasting angle is 45°-60°, and the sandblasting time is 3-5min; the grinding uses an 80-120 mesh grinding wheel.

5. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (2) ④, the plasma surface treatment uses argon gas with a purity of ≥99.99%, a treatment power of 1.5-2kW, and a treatment time of 2-3min; the silane coupling agent treatment uses a KH-550 solution with a mass fraction of 1%-2%, a soaking time of 5-10min, and drying at 80-100℃ for 10-15min.

6. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (3) ②, the pretreatment of the hot pressing mold includes cleaning and degreasing, applying release agent, and preheating. The preheating temperature is PTFE: 180-200℃, PI: 250-280℃, PEEK: 300-320℃, and the preheating time is 15-20min. The pressurization rate is 0.1 MPa / min, and the preset pressure is PTFE: 1-2 MPa, PI: 2-3 MPa, PEEK: 3-5 MPa; The constant temperature insulation temperature is PTFE: 190℃, PI: 260℃, PEEK: 310℃; the cooling rate is ≤5℃ / min, and the depressurization rate is 0.05MPa / min.

7. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (4) ①, the roundness of the bearing sleeve part is ≤0.01mm and the parallelism of the end face is ≤0.02mm; in step (4) ②, the polishing speed is 1000-1500r / min and the polishing time is 5-10min.

8. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (5) ①, the mechanical performance testing requirements are as follows: the hardness of the low carbon steel matrix is ​​≥120HB, the hardness of the brass matrix is ​​≥80HB, and the hardness of the aluminum alloy matrix is ​​≥60HB; the tensile strength of the composite material is ≥200MPa, and the elongation at break is ≥5%; in the temperature resistance test, the PI bearing is ≤260℃, the PEEK bearing is ≤250℃, the PTFE bearing is ≤200℃, and there is no deformation or crack after 24 hours of heat preservation.

9. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, In step (6) ①, individual bearings are wrapped in plastic film and placed in batches into foam boxes or cartons with desiccant inside; the packaging is labeled with the product name, specifications, batch number, production date, and shelf life.

10. The processing method of the metal-polymer composite self-lubricating bearing material according to claim 1, characterized in that, It also includes precautions: the moisture content of polymer raw materials should be ≤0.5%; the interval between pretreatment of the metal matrix and composite molding should not exceed 2 hours; molding parameters should be adjusted strictly according to the type of polymer; equipment should be maintained and testing equipment calibrated regularly; if the blank or finished product is unqualified, the cause should be analyzed and reprocessed.