Wear-resistant and corrosion-resistant metal fan cover and manufacturing method thereof

Abstract

The invention belongs to the technical field of metal protection structures and surface engineering, and particularly relates to a manufacturing method of a wear-resistant and corrosion-resistant metal fan cover. The fan cover is prepared by compounding a steel-based material synergistically modified by nitrogen plasma, N-phenyl vinyl amide, a heat-resistant stabilizer, an antioxidant, a curing agent, a flexibilizer and a surfactant. Through synergistic modification of nitrogen plasma, acetylene gas, yttrium oxide and gamma-aminopropyltriethoxysilane, a compact carbon nitrogen-rare earth composite strengthening layer is formed on the surface of a steel base, and then the high-binding-force protective film is formed through crosslinking and curing of small organic molecules. The surface hardness of the obtained fan housing reaches 900 HV, the wear rate is only 1.2 * 10 mm / N.m, the fan housing is free of corrosion after salt spray for 72 hours, and the bonding strength reaches 25 MPa. According to the synergistic modification system, the wear resistance and corrosion resistance of the metal fan cover are remarkably improved, and the metal fan cover is suitable for protection application in high-temperature, high-humidity and corrosive industrial environments.

Description

Technical Field

[0001] This invention belongs to the field of metal protective structure and surface engineering technology, and particularly relates to a method for manufacturing a wear-resistant and corrosion-resistant metal wind shield. Background Technology

[0002] Metal fan hoods, as crucial components in industrial equipment for airflow guidance, protection, and heat insulation, are widely used in metallurgy, chemical engineering, power generation, and machinery manufacturing. During long-term service, metal fan hoods are constantly exposed to the combined effects of high temperatures, corrosive gases, and high-speed particle flows, making them highly susceptible to surface wear, oxidation, and corrosion. This leads to decreased structural strength, shortened service life, and even safety hazards. Traditional metal fan hoods are mostly made of ordinary stainless steel or carbon steel, which, while possessing a certain level of mechanical strength, have limited surface protection capabilities and struggle to maintain stable performance in highly corrosive and abrasive environments over extended periods.

[0003] Existing methods for improving the wear resistance and corrosion resistance of metal windshields mainly include surface spraying, chemical plating, nitriding, and organic coating protection. However, spraying or plating technologies are prone to peeling due to thermal stress under high temperature and thermal cycling conditions; although nitriding or carburizing modification can improve surface hardness, the modified layer thickness is limited, and its corrosion resistance is poor in strong acid and alkali environments; while organic coatings, although possessing certain protective capabilities, have insufficient heat resistance and mechanical strength, and are prone to aging, cracking, or peeling in long-term abrasive environments, making it difficult to achieve a high-durability protective effect.

[0004] To address the aforementioned issues, there is an urgent need for an innovative metal hood material system that can balance high hardness, high bonding strength, and excellent corrosion resistance. Summary of the Invention

[0005] To overcome the problems of insufficient wear resistance and corrosion resistance, weak bonding strength of modified layers, and short protective life of metal wind shields in the aforementioned background technologies, the present invention aims to provide a wear-resistant and corrosion-resistant metal wind shield and its manufacturing method. Through innovative synergistic modification and composite protective structure design, high strength and high stability of the metal surface are achieved. This invention utilizes nitrogen plasma synergistic modification to introduce carbon source activators, rare earth oxides, and trace amounts of silane coupling agents onto the steel substrate surface, constructing a dense carbon-nitrogen-rare earth composite reinforcing layer. This is then combined with an N-phenylvinylamide organic small molecule composite coating to form an organic-inorganic integrated protective film with excellent adhesion, thereby achieving a dual protection mechanism on the metal wind shield surface. This invention, through plasma synergistic modification and organic small molecule cross-linking composite, enables the metal wind shield to simultaneously possess high hardness, high bonding strength, and excellent corrosion resistance, significantly improving its service life in high-temperature, high-corrosion, and high-wear environments.

[0006] The objective of this invention can be achieved through the following technical solutions: A wear-resistant and corrosion-resistant metal hood comprises the following raw materials in parts by weight: 80-100 parts of steel-based material synergistically modified with nitrogen plasma; 10-15 parts of N-phenylvinylamide; 1-3 parts of heat-resistant stabilizer; 2-4 parts of antioxidant; 3-5 parts of curing agent; 2-3 parts of toughening agent; and 1-2 parts of surfactant. The steel-based material synergistically modified with nitrogen plasma is an innovative modified metal material that forms a dense carbon-nitrogen-rare earth composite reinforcing layer on the steel surface through synergistic treatment with nitrogen plasma, carbon source activator, rare earth oxides, and trace amounts of silane coupling agent. This layer possesses high hardness, high bonding strength, and excellent corrosion resistance.

[0007] Optionally, the steel-based material modified by nitrogen plasma comprises the following raw materials in parts by weight: 80-90 parts of stainless steel substrate; 3-6 parts of acetylene gas; 1-3 parts of yttrium oxide; 0.5-1.5 parts of γ-aminopropyltriethoxysilane; and 5-8 parts of nitrogen-ammonia mixed initiator. The nitrogen-ammonia mixed initiator is a reactive gas system composed of nitrogen and ammonia mixed in a volume ratio of 3:1. During plasma modification, it simultaneously provides active nitrogen atoms and hydrogen radicals to excite the formation of a dense carbon-nitrogen composite layer on the steel surface, significantly improving the material's wear resistance and corrosion resistance.

[0008] Optionally, the preparation method of the steel-based material synergistically modified by nitrogen plasma includes the following steps: (1) The stainless steel substrate is mechanically polished, degreased and pickled to remove the surface oxide layer and impurities. Then it is rinsed with deionized water and dried to obtain a clean and smooth substrate surface. (2) Nitrogen and ammonia are mixed at a volume ratio of 3:1 to form a plasma reaction gas; at the same time, acetylene, yttrium oxide powder vapor and γ-aminopropyltriethoxysilane vapor are introduced into the system to prepare a synergistic modified atmosphere. (3) The steel substrate is placed in a vacuum reaction chamber and a synergistic modification atmosphere is introduced to allow active nitrogen, carbon, silicon and rare earth elements to synergistically penetrate into the steel surface to form a dense carbon-nitrogen-rare earth composite layer. (4) After the modification is completed, the temperature is slowly reduced to room temperature, cooled in an inert gas atmosphere, and lightly passivated with dilute nitric acid solution to stabilize the surface structure and prevent secondary oxidation, thus obtaining a steel-based material modified by nitrogen plasma.

[0009] Optionally, the reaction conditions for step (1) are: after polishing, acid washing with 10-15wt% nitric acid solution for 5-10 min, washing with deionized water, and drying at 100-120℃ for 30-60 min.

[0010] Optionally, the reaction conditions in step (2) are as follows: nitrogen and ammonia are mixed in a volume ratio of 3:1, the acetylene flow rate is 20-40 sccm, the yttrium oxide evaporation rate is 0.5-1.0 g / h, and the γ-aminopropyltriethoxysilane vaporization temperature is 80-100 °C.

[0011] Optionally, the reaction conditions in step (3) are as follows: nitrogen plasma discharge treatment is carried out for 1 to 3 hours at a vacuum of 50 to 150 Pa and a temperature of 450 to 550 °C, with a power of 400 to 800 W.

[0012] Optionally, the reaction conditions for step (4) are as follows: after the treatment is completed, the mixture is naturally cooled to room temperature under nitrogen protection, then passivated with 2-5 wt% dilute nitric acid solution for 3-5 min, rinsed with anhydrous ethanol and dried for later use.

[0013] Optionally, the heat stabilizer is a mixture of pentaerythritol and calcium stearate in a mass ratio of 1:2; the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1; the curing agent is a mixture of hexamethylenetetramine and phthalic anhydride in a mass ratio of 3:2; the toughening agent is a mixture of carboxylated nitrile rubber and epoxidized soybean oil in a mass ratio of 2:1; and the surfactant is a mixture of nonylphenol polyoxyethylene ether and hexadecyltrimethylammonium bromide in a mass ratio of 1:1.

[0014] Optionally, a method for manufacturing a wear-resistant and corrosion-resistant metal wind shield includes the following steps: S1, weigh the steel-based material modified by nitrogen plasma, N-phenylvinylamide, heat stabilizer, antioxidant, curing agent, toughening agent and surfactant, add each component to a closed stirring tank in sequence and stir to make the components fully mixed and uniform to form a composite system with good flowability; S2, the composite system is placed in a vacuum impregnation device, and the steel-based material workpiece that has been synergistically modified is completely immersed in the system to obtain the impregnated workpiece, so that the organic phase and additives can fully penetrate into the pores of the metal surface and form a preliminary bonding layer with it. S3. After the impregnated workpiece is removed, it is placed in a thermosetting oven. N-phenylvinylamide and curing agent undergo a cross-linking reaction to generate a dense organic-inorganic composite protective layer that is firmly attached to the surface of the metal substrate. S4. The cured metal hood is naturally cooled to room temperature under nitrogen protection. After being removed, the edges are trimmed and the surface is finely polished. Finally, the sample is subjected to Vickers hardness test, salt spray corrosion test and wear resistance test. After confirming that its surface hardness, corrosion resistance and wear resistance all meet the standard requirements, the finished wear-resistant and corrosion-resistant metal hood is obtained.

[0015] Optionally, the reaction conditions for step S1 are: mixing temperature 80–100℃, stirring speed 300–500 rpm, stirring time 30–60 min, maintaining a uniform system without stratification; the reaction conditions for step S2 are: vacuum degree 0.05–0.1 MPa, immersion time 30–45 min, the workpiece completely immersed in the mixture, and a constant temperature of 80–90℃ maintained to promote penetration and bonding; the reaction conditions for step S3 are: thermosetting temperature 120–160℃, holding time 1–2 h, heating rate 2–3℃ / min, forming a dense organic-inorganic crosslinked film; the reaction conditions for step S4 are: natural cooling under nitrogen protection, polishing after cooling to 25℃, and drying at 60–80℃ for 30 min before testing to remove residual surface moisture.

[0016] The beneficial effects of this invention are: This invention utilizes the synergistic effect of nitrogen plasma, carbon source activators, rare earth oxides, and silane coupling agents to form a dense and gradient-transition carbonitridium-rare earth composite reinforcement layer in situ on a steel substrate surface. This reinforcement layer exhibits metallurgical bonding characteristics with the substrate, significantly improving surface hardness and wear resistance while enhancing the adhesion and structural stability of the modified layer, effectively avoiding the problem of traditional spraying or plating easily peeling off under high temperature and thermal shock environments. This invention creatively introduces N-phenylvinylamide as an organic small-molecule co-crosslinking monomer, which undergoes a directional crosslinking reaction with the curing agent during the curing stage to construct an organic-inorganic chemical bond interface. This interface layer can form a stable chemical bond between the carbonitridium composite layer and the outer organic film, resulting in a highly dense and effective shielding layer that significantly reduces the penetration rate of corrosive media and inhibits the initiation and propagation of microcracks, thereby achieving long-term corrosion resistance. This invention is innovative in terms of structure and reaction system. Through the dual construction mechanism of "plasma multiphase activation synergistic modification + N-phenylvinylamide crosslinked film", the protective layer of the metal windshield is transformed from the traditional physical adhesion to a chemical synergistic bonding structure, which fundamentally improves its wear resistance, corrosion resistance and service stability. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1 The infrared spectra of unmodified steel-based materials and steel-based materials synergistically modified with nitrogen plasma are compared. Figure 2 Comparison of surface hardness test results for samples with different formulation ratios; Figure 3 A comparison chart of wear resistance test results for samples with different formulation ratios; Figure 4Comparison of salt spray corrosion test and film bonding strength test results for samples with different ratios. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Equivalent adjustments made without departing from the spirit and essence of the present invention should also be considered to fall within the protection scope of the present invention.

[0020] Example 1 The purpose of this embodiment is to verify that when the proportions of each major component are at their upper limits, a higher organic phase content in the material improves the coating density, interfacial adhesion, and corrosion resistance.

[0021] S1. Take 90 parts of stainless steel substrate and place them in a vacuum reaction chamber. Sequentially introduce 6 parts of acetylene gas, 3 parts of yttrium oxide, 1.5 parts of γ-aminopropyltriethoxysilane, and 8 parts of a nitrogen-ammonia mixed initiator. Mix nitrogen and ammonia at a volume ratio of 3:1 and discharge at a vacuum of 150 Pa and a temperature of 550 °C for 3 hours with a power of 800 W. After treatment, slowly cool to room temperature and passivate with 3 wt% dilute nitric acid solution for 5 minutes. Dry to obtain the modified steel-based material. S2, weigh 100 parts of the modified steel-based material, add 15 parts of N-phenylvinylamide, 3 parts of heat-resistant stabilizer, 4 parts of antioxidant, 5 parts of curing agent, 3 parts of toughening agent and 2 parts of surfactant, place in a closed mixing vessel and stir at 100℃ for 60 min to form a uniform mixing system; completely immerse the steel-based workpiece in the system and immerse it for 45 min under vacuum of 0.1 MPa and constant temperature of 90℃; S3, remove the immersed workpiece and place it in a curing oven. Keep it at 160℃ for 2 hours to allow N-phenylvinylamide and curing agent to fully crosslink and form an organic-inorganic composite protective layer. After cooling to room temperature, polish and test. The resulting hood surface forms a continuous and dense film layer with a hardness of HV950 or higher. No rust was observed after 96 hours of salt spray testing.

[0022] Example 2 The purpose of this embodiment is to evaluate the structural balance and overall performance between the modified layer and the organic composite membrane when the components are in an intermediate ratio.

[0023] S1, take 85 parts of stainless steel substrate, add 4.5 parts of acetylene gas, 2 parts of yttrium oxide, 1 part of γ-aminopropyltriethoxysilane and 6.5 parts of nitrogen-ammonia mixed initiator. The reaction conditions are vacuum degree 100Pa, temperature 500℃, time 2h, power 600W. After the reaction, it is slowly cooled under nitrogen atmosphere and passivated with 4wt% dilute nitric acid solution for 4min. After drying, the modified steel-based material is obtained. Figure 1The nitrogen plasma-modified steel substrate exhibits new absorption peaks at 1560, 1200, 1050, and 850 cm⁻¹, indicating that the nitrogen plasma and silane react synergistically to generate new C–N, Si–O–Si, and Si–C bonds. The significantly enhanced N–H and O–H stretching vibrations at 3400 cm⁻¹ indicate the successful introduction of surface-active nitrogen atoms. The enhanced C=O stretching peak at 1640 cm⁻¹ reflects the enhanced bonding between the organic phase and the steel substrate. The enhanced Si–O–C vibration at 1100 cm⁻¹ indicates the formation of an organosilicon framework. The overall spectrum shows a stable baseline and symmetrical peaks, demonstrating that the modified layer is dense and uniform, providing a structural basis for forming a high-bonding-strength and corrosion-resistant composite film. S2, weigh 90 parts of modified steel-based material, add 12 parts of N-phenylvinylamide, 2 parts of heat-resistant stabilizer, 3 parts of antioxidant, 4 parts of curing agent, 2.5 parts of toughening agent and 1.5 parts of surfactant, stir at 90℃ for 45 min to obtain a uniform mixture, immerse the workpiece in the system and soak for 40 min under vacuum of 0.08 MPa and constant temperature of 85℃. S3, remove the workpiece and place it in the curing oven, keep it at 140℃ for 1.5h to complete the cross-linking curing; after cooling, polish and test, the surface hardness of the resulting metal hood is about HV900, there are no obvious corrosion spots in the salt spray test for 72h, and the bonding strength reaches 25MPa.

[0024] Example 3 The purpose of this embodiment is to verify the variation law of the modified layer and composite film forming ability and corrosion and wear resistance when the lower limit ratio of each component is taken.

[0025] S1. Take 80 parts of stainless steel substrate, add 3 parts of acetylene gas, 1 part of yttrium oxide, 0.5 parts of γ-aminopropyltriethoxysilane and 5 parts of nitrogen-ammonia mixed initiator, and discharge treat for 1 hour under vacuum of 50 Pa, temperature of 450 °C and power of 400 W; after treatment, passivate with 2 wt% dilute nitric acid solution for 3 min and dry to obtain modified steel-based material; S2, weigh 80 parts of modified steel-based material, add 10 parts of N-phenylvinylamide, 1 part of heat-resistant stabilizer, 2 parts of antioxidant, 3 parts of curing agent, 2 parts of toughening agent and 1 part of surfactant, stir at 80℃ for 30 min to form a mixed system; immerse the workpiece in a vacuum of 0.05MPa and a constant temperature of 80℃ for 30 min. S3, after impregnation, the workpiece is placed in a curing oven and kept at 120℃ for 1 hour for cross-linking curing. After cooling and polishing, the coating is tested and found to have good density and surface hardness of HV860. Only slight oxidation spots appeared in the salt spray test for 48 hours, indicating that the system still has stable protective performance at low ratios.

[0026] Comparative Example 1 The purpose of this comparative example is to verify the changes in the bonding performance and corrosion resistance between the modified layer and the organic composite film when only nitrogen plasma modification is used.

[0027] S1, take 85 parts of stainless steel substrate, add 6.5 parts of nitrogen-ammonia mixed initiator, without adding acetylene, yttrium oxide and γ-aminopropyltriethoxysilane, the reaction conditions are vacuum degree 100Pa, temperature 500℃, time 2h, power 600W; after the reaction, it is slowly cooled under nitrogen atmosphere and passivated with 4wt% dilute nitric acid solution for 4min, and dried to obtain modified steel-based material; S2, weigh 90 parts of modified steel-based material, add 12 parts of N-phenylvinylamide, 2 parts of heat-resistant stabilizer, 3 parts of antioxidant, 4 parts of curing agent, 2.5 parts of toughening agent and 1.5 parts of surfactant, stir at 90℃ for 45 min to obtain a uniform mixture, immerse the workpiece in the system and soak for 40 min under vacuum of 0.08 MPa and constant temperature of 85℃. S3, the workpiece is removed and placed in a curing oven, and the cross-linking curing is completed at 140℃ for 1.5h. After cooling, it is polished and tested. The surface hardness and bonding strength are lower than those in Example 2, and the corrosion resistance in the salt spray test is reduced.

[0028] Comparative Example 2 The purpose of this comparative example is to verify the effect of the lack of nitriding and rare earth / silane synergy on the film density and adhesion when only carbon source activation modification is used.

[0029] S1, take 85 parts of stainless steel substrate, add 4.5 parts of acetylene gas, without adding yttrium oxide, γ-aminopropyltriethoxysilane and nitrogen-ammonia mixed initiator, the reaction conditions are vacuum degree 100Pa, temperature 500℃, time 2h, power 600W; after the reaction, it is slowly cooled under nitrogen atmosphere and passivated with 4wt% dilute nitric acid solution for 4min, and dried to obtain modified steel-based material; S2, weigh 90 parts of modified steel-based material, add 12 parts of N-phenylvinylamide, 2 parts of heat-resistant stabilizer, 3 parts of antioxidant, 4 parts of curing agent, 2.5 parts of toughening agent and 1.5 parts of surfactant, stir at 90℃ for 45 min to obtain a uniform mixture, immerse the workpiece in the system and soak for 40 min under vacuum of 0.08 MPa and constant temperature of 85℃. S3, the workpiece is removed and placed in a curing oven, and the cross-linking curing is completed at 140°C for 1.5 hours. After cooling, it is polished and tested. The film bonding strength and corrosion resistance are lower than those in Example 2.

[0030] Comparative Example 3 The purpose of this comparative example is to verify the impact of the lack of synergistic effects of nitriding, carbide and silane coupling on performance when only rare earth oxides are used for modification.

[0031] S1, take 85 parts of stainless steel substrate, add 2 parts of yttrium oxide, without adding acetylene gas, γ-aminopropyltriethoxysilane and nitrogen-ammonia mixed initiator, the reaction conditions are vacuum degree 100Pa, temperature 500℃, time 2h, power 600W; after the reaction, it is slowly cooled under nitrogen atmosphere and passivated with 4wt% dilute nitric acid solution for 4min, and dried to obtain modified steel-based material; S2, weigh 90 parts of modified steel-based material, add 12 parts of N-phenylvinylamide, 2 parts of heat-resistant stabilizer, 3 parts of antioxidant, 4 parts of curing agent, 2.5 parts of toughening agent and 1.5 parts of surfactant, stir at 90℃ for 45 min to obtain a uniform mixture, immerse the workpiece in the system and soak for 40 min under vacuum of 0.08 MPa and constant temperature of 85℃. S3, the workpiece was removed and placed in a curing oven, and kept at 140℃ for 1.5h to complete the cross-linking curing; after cooling, it was polished and tested, and the overall wear resistance and corrosion resistance were weaker than those of Example 2.

[0032] Comparative Example 4 The purpose of this comparative example is to verify the performance differences caused by the lack of a chemical reinforcement layer when only silane coupling modification is used, although it improves wetting and interfacial energy.

[0033] S1, take 85 parts of stainless steel substrate, add 1 part of γ-aminopropyltriethoxysilane, without adding acetylene gas, yttrium oxide and nitrogen-ammonia mixed initiator, the reaction conditions are vacuum degree 100Pa, temperature 500℃, time 2h, power 600W; after the reaction, it is slowly cooled under nitrogen atmosphere and passivated with 4wt% dilute nitric acid solution for 4min, and dried to obtain modified steel-based material; S2, weigh 90 parts of modified steel-based material, add 12 parts of N-phenylvinylamide, 2 parts of heat-resistant stabilizer, 3 parts of antioxidant, 4 parts of curing agent, 2.5 parts of toughening agent and 1.5 parts of surfactant, stir at 90℃ for 45 min to obtain a uniform mixture, immerse the workpiece in the system and soak for 40 min under vacuum of 0.08 MPa and constant temperature of 85℃. S3, the workpiece was removed and placed in a curing oven, and the cross-linking curing was completed at 140°C for 1.5 hours. After cooling, it was polished and tested. The film strength and corrosion resistance were significantly lower than those in Example 2.

[0034] Comparative Example 5 The purpose of this comparative example is to verify the changes in the cross-linking density and interfacial bonding performance of the composite layer when small organic molecules are removed.

[0035] S1, take 85 parts of stainless steel substrate, add 4.5 parts of acetylene gas, 2 parts of yttrium oxide, 1 part of γ-aminopropyltriethoxysilane and 6.5 parts of nitrogen-ammonia mixed initiator. The reaction conditions are vacuum degree 100 Pa, temperature 500 ℃, time 2 h, power 600 W. After the reaction, it is slowly cooled under nitrogen atmosphere and passivated with 4 wt% dilute nitric acid solution for 4 min. After drying, the modified steel-based material is obtained. S2, weigh 90 parts of modified steel-based material, add 2 parts of heat-resistant stabilizer, 3 parts of antioxidant, 4 parts of curing agent, 2.5 parts of toughening agent and 1.5 parts of surfactant, stir at 90℃ for 45 min to obtain a uniform mixture, immerse the workpiece in the system, and soak for 40 min under vacuum of 0.08 MPa and constant temperature of 85℃. S3, remove the workpiece and place it in a curing oven, keep it at 140℃ for 1.5h to complete the curing; after cooling, polish and test, the film density and bonding strength are lower than in Example 2, and the salt spray test corrosion resistance is reduced.

[0036] Performance testing 1. Surface hardness test This test was used to evaluate the effect of different modification systems on the surface strengthening effect of metal wind turbines. Samples from Example 2 and various comparative examples were selected. Five different points on the sample surface were randomly chosen using a Vickers microhardness tester for measurement. The applied force was 0.05 kgf, and the load was maintained for 10 seconds. The hardness values ​​at each point were recorded, and the average value was taken as the surface hardness of the sample. By comparing the hardness results of each sample, the contribution of the synergistic modification system to the compactness and bonding strength of the metal surface strengthening layer can be directly reflected.

[0037] 2. Wear resistance test This test was used to verify the effects of synergistic modification and cross-linking of organic small molecules on tribological properties. Example and comparative samples were selected and tested on a reciprocating tribological testing machine. The friction pair was a 6mm diameter GCr15 steel ball, the load was set to 5N, the frequency to 2Hz, the reciprocating stroke to 5mm, the test time to 30min, and the ambient temperature to 25℃. After the test, the wear track morphology was observed using a three-dimensional profilometer, and the wear track width and depth were measured. The shallower the wear track and the less surface damage, the better the wear resistance of the sample.

[0038] 3. Salt spray corrosion test This test was used to evaluate the corrosion resistance of different modified systems to metal windshields. The test was conducted according to GB / T10125-2021 standard. Samples were placed in a neutral salt spray chamber with a 5wt% sodium chloride solution as the spray medium, and the temperature was maintained at 35℃. Test times were 24h, 48h, and 72h. After the test, the sample surface was observed for rust, corrosion spots, or film peeling, and surface changes were recorded using an optical microscope. A longer salt spray test time with no obvious surface corrosion indicates a denser protective layer and superior corrosion resistance.

[0039] 4. Membrane bonding strength test This test was used to determine the adhesion between organic-inorganic composite films and metal substrates. The pull-off method was employed. A standard metal pull ring was fixed to the sample surface with epoxy resin. After curing at room temperature, a vertical pull force was applied using a pull-off tester until the film separated from the substrate. The maximum force during pull-off was recorded, and the average of five measurements was taken as the film bonding strength. Higher bonding strength indicates a stronger bond between the composite film and the substrate. Comparative results show that the synergistic modification system significantly improves adhesion, changing the film failure mode from interfacial peeling to internal coagulation failure, demonstrating excellent interfacial bonding quality. Table 1 compares the performance test results of different samples. As can be seen from Table 1, Example 2 performed best in all test items, and its overall performance was significantly better than that of Example 1, Example 3 and all comparative sample samples. Figure 2 The surface hardness reached 900 HV, which is approximately 2 and 3 percentage points higher than 880 HV in Example 1 and 870 HV in Example 3, respectively, and 11 percentage points higher than 810 HV in Comparative Example 4. This indicates that the combined action of nitrogen plasma, carbon source, rare earth oxides, and silane coupling agent forms a dense carbon-nitrogen-rare earth composite layer on the steel substrate surface, resulting in a more stable crystal structure and significantly improved hardness and impact resistance.

[0040] Regarding wear rate, Figure 3 Example 2 is 1.2 × 10⁻ 5 mm³ / N·m, the lowest value among all samples, compared to 1.5 × 10⁻ in Example 3. 5 mm³ / N·m decreased by 20%, compared to 2.0×10⁻ in Comparative Example 1. 5 The wear resistance of the synergistic modified layer is reduced by 40% (mm³ / N·m). This indicates that the synergistic modified layer has extremely strong wear resistance. The active nitrogen atoms provided by nitrogen plasma form a nitrided layer, and the carbon source provided by acetylene gas generates a carbide phase. The two work synergistically to construct a high-hardness nitrogen-carbon composite layer on the surface, which significantly reduces the wear rate of the metal under frictional load.

[0041] In salt spray tests, Figure 4Example 2 showed no rust for 72 hours, demonstrating significantly better protection than other samples. Its anti-corrosion effect stems from its multi-layered protective structure: the innermost carbon-nitrogen composite layer provides electron blocking, the middle rare-earth oxide layer has a self-passivating effect, and the outermost layer, formed by an organic cross-linked film, creates a continuous and dense interfacial barrier that effectively inhibits the penetration of oxidizing media and chloride ions.

[0042] Regarding the film bonding strength, Figure 4 Example 2 achieved a strength of 25 MPa, which is higher than the 23 MPa of Example 1 and the 22 MPa of Example 3, and more than 50% higher than the 16 MPa of Comparative Example 4. This is because N-phenylvinylamide and silane coupling agent jointly participate in the crosslinking reaction during the curing stage, forming a stable organic-inorganic bond interface, which significantly enhances the adhesion of the film layer and makes it less prone to detachment under thermal cycling or mechanical loads.

[0043] The performance of the comparative samples all showed a significant decline. Using only nitrogen plasma, carbon sources, rare earth oxides, or silane coupling agents resulted in varying degrees of performance defects. For example, samples using only nitrogen plasma showed improved hardness, but the surface structure was loose, leading to poor corrosion resistance; samples activated only by carbon sources showed some strengthening effect, but the bonding force was insufficient; samples modified only by rare earths had high hardness but increased brittleness; and samples coupled only by silanes improved surface wettability but lacked stable structural strengthening.

[0044] Although Comparative Example 5, which lacks organic small molecule crosslinking, exhibits a certain surface strengthening effect, its film bonding strength is only 18 MPa, indicating that microcracks and pores exist at the interlayer interface when organic network support is lacking, resulting in insufficient overall structural stability.

[0045] In summary, Example 2 significantly improved the hardness, wear resistance, corrosion resistance and bonding strength of the steel-based wind shield through multi-factor synergistic modification, and successfully constructed a highly dense composite layer with gradient structure characteristics on the surface, demonstrating outstanding creativity and practical application advantages.

Claims

1. A wear-resistant and corrosion-resistant metal fan cover, characterized in that, The raw materials comprise the following parts by weight: 80-100 parts of steel-based material synergistically modified with nitrogen plasma; 10-15 parts of N-phenylvinylamide; 1-3 parts of heat-resistant stabilizer; 2-4 parts of antioxidant; 3-5 parts of curing agent; 2-3 parts of toughening agent; and 1-2 parts of surfactant. The steel-based material synergistically modified with nitrogen plasma is an innovative modified metal material that forms a dense carbon-nitrogen-rare earth composite reinforcing layer on the surface of the steel base through synergistic treatment with nitrogen plasma, carbon source activator, rare earth oxides, and trace amounts of silane coupling agent.

2. The wear-resistant and corrosion-resistant metal wind shield according to claim 1, characterized in that, The steel-based material modified by nitrogen plasma comprises the following raw materials in parts by weight: 80-90 parts stainless steel substrate; 3-6 parts acetylene gas; 1-3 parts yttrium oxide; 0.5-1.5 parts γ-aminopropyltriethoxysilane; and 5-8 parts nitrogen-ammonia mixed initiator. The nitrogen-ammonia mixed initiator is a reactive gas system composed of nitrogen and ammonia mixed in a volume ratio of 3:1, which simultaneously provides active nitrogen atoms and hydrogen free radicals during the plasma modification process.

3. A wear-resistant and corrosion-resistant metal windshield according to any one of claims 1 or 2, characterized in that, The preparation method of the steel-based material synergistically modified by nitrogen plasma includes the following steps: (1) The stainless steel substrate is mechanically polished, degreased and pickled to remove the surface oxide layer and impurities. Then it is rinsed with deionized water and dried to obtain a clean and smooth substrate surface. (2) Nitrogen and ammonia are mixed at a volume ratio of 3:1 to form a plasma reaction gas; at the same time, acetylene, yttrium oxide powder vapor and γ-aminopropyltriethoxysilane vapor are introduced into the system to prepare a synergistic modified atmosphere. (3) The steel substrate is placed in a vacuum reaction chamber and a synergistic modification atmosphere is introduced to allow active nitrogen, carbon, silicon and rare earth elements to synergistically penetrate into the steel surface to form a dense carbon-nitrogen-rare earth composite layer. (4) After the modification is completed, the temperature is slowly reduced to room temperature, cooled in an inert gas atmosphere, and lightly passivated with dilute nitric acid solution to stabilize the surface structure and prevent secondary oxidation, thus obtaining a steel-based material modified by nitrogen plasma.

4. The wear-resistant and corrosion-resistant metal wind shield according to claim 3, characterized in that, The reaction conditions for step (1) are as follows: after polishing, acid washing with 10-15wt% nitric acid solution for 5-10 min, cleaning with deionized water, and drying at 100-120℃ for 30-60 min.

5. The wear-resistant and corrosion-resistant metal wind shield according to claim 3, characterized in that, The reaction conditions for step (2) are as follows: nitrogen and ammonia are mixed in a volume ratio of 3:1, the acetylene flow rate is 20-40 sccm, the yttrium oxide evaporation rate is 0.5-1.0 g / h, and the γ-aminopropyltriethoxysilane vaporization temperature is 80-100℃.

6. The wear-resistant and corrosion-resistant metal wind shield according to claim 3, characterized in that, The reaction conditions for step (3) are as follows: nitrogen plasma discharge treatment is carried out for 1 to 3 hours at a vacuum of 50 to 150 Pa and a temperature of 450 to 550 °C, with a power of 400 to 800 W.

7. The wear-resistant and corrosion-resistant metal wind shield according to claim 3, characterized in that, The reaction conditions for step (4) are as follows: after the treatment is completed, the mixture is naturally cooled to room temperature under nitrogen protection, then passivated with 2-5 wt% dilute nitric acid solution for 3-5 min, rinsed with anhydrous ethanol and dried for later use.

8. The wear-resistant and corrosion-resistant metal wind shield according to claim 1, characterized in that, The heat stabilizer is a mixture of pentaerythritol and calcium stearate in a mass ratio of 1:2; the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1; the curing agent is a mixture of hexamethylenetetramine and phthalic anhydride in a mass ratio of 3:2; the toughening agent is a mixture of carboxylated nitrile rubber and epoxidized soybean oil in a mass ratio of 2:1; and the surfactant is a mixture of nonylphenol polyoxyethylene ether and hexadecyltrimethylammonium bromide in a mass ratio of 1:

1.

9. A method for manufacturing a wear-resistant and corrosion-resistant metal wind shield, wherein the wear-resistant and corrosion-resistant metal wind shield is as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1, weigh out the steel-based material modified by nitrogen plasma, N-phenylvinylamide, heat stabilizer, antioxidant, curing agent, toughening agent and surfactant, add each component to a closed stirring tank in sequence and stir to form a composite system with good flowability; S2, The composite system is placed in a vacuum impregnation device, and the synergistically modified steel-based material workpiece is completely immersed in the system to obtain the impregnated workpiece; S3. After the impregnated workpiece is removed, it is placed in a thermosetting oven. N-phenylvinylamide and curing agent undergo a cross-linking reaction to generate a dense organic-inorganic composite protective layer that is firmly attached to the surface of the metal substrate. S4. The cured metal hood is naturally cooled to room temperature under nitrogen protection. After being removed, the edges are trimmed and the surface is finely polished. Finally, the sample is subjected to Vickers hardness test, salt spray corrosion test and wear resistance test. After confirming that its surface hardness, corrosion resistance and wear resistance all meet the standard requirements, the finished wear-resistant and corrosion-resistant metal hood is obtained.

10. The method for manufacturing a wear-resistant and corrosion-resistant metal wind shield according to claim 9, characterized in that, The reaction conditions for step S1 are: mixing temperature 80-100℃, stirring speed 300-500rpm, and stirring time 30-60min; the reaction conditions for step S2 are: vacuum degree 0.05-0.1MPa, immersion time 30-45min, the workpiece is completely immersed in the mixture, and the temperature is maintained at 80-90℃; the reaction conditions for step S3 are: thermosetting temperature 120-160℃, holding time 1-2h, and heating rate 2-3℃ / min; the reaction conditions for step S4 are: natural cooling under nitrogen protection, polishing after cooling to 25℃, and drying at 60-80℃ for 30min before testing.

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