Nickel composite materials suitable for improving vibration reduction and noise reduction performance and their preparation methods
By covering the surface of a nickel substrate with a dense nanofiber mesh and controlling the spinning parameters, the problem of weak bonding force of nickel composite materials was solved, and its sound absorption, damping and mechanical properties were improved, achieving better vibration reduction and noise reduction effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TSINGHUA UNIVERSITY
- Filing Date
- 2026-03-03
- Publication Date
- 2026-05-26
AI Technical Summary
The porous structure of the nickel substrate during the preparation of nickel composite materials results in weak bonding of functional materials, making them prone to detachment and limiting their application.
A dense nanofiber web is coated on the surface of a nickel substrate and extended through the internal pores of the nickel substrate. By controlling spinning parameters such as needle extrusion speed, spinning voltage, and the distance between the needle and the spinning plate, a uniform and dense fiber web structure is formed, which enhances the bonding force.
The sound absorption, damping and mechanical properties of nickel composite materials were improved, resulting in better vibration reduction and noise reduction, as well as improved production efficiency and material uniformity.
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Figure CN122082142A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of this application relate to the field of processing fiber products, and particularly to a nickel composite material suitable for improving vibration reduction and noise reduction performance and its preparation method. Background Technology
[0002] The statements herein are provided merely as background information in connection with this application and do not necessarily constitute prior art.
[0003] Nickel composites typically use porous nickel or nickel-based foam metal as a framework, and are formed by loading nanofibers, oxides, or other functional materials. They combine the good electrical and thermal conductivity of nickel with the surface functionality of reinforcing components. However, during the preparation process, due to the porous structure of the nickel substrate, the functional materials loaded often exhibit weak adhesion to the nickel substrate and are prone to detachment, limiting the application of nickel composites. Summary of the Invention
[0004] A brief overview of this application is provided below to offer a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the application. It is not intended to identify key or essential parts of the application, nor is it intended to limit its scope. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.
[0005] This application provides a nickel composite material suitable for improving vibration reduction and noise reduction performance, comprising: a nickel substrate with a foam-like porous structure, and a dense nanofiber mesh composed of a spinnable polymer covering the surface of the nickel substrate, the fiber mesh extending through the internal pores of the nickel substrate.
[0006] The nickel composite material provided in the embodiments of this application, which is suitable for improving vibration reduction and noise reduction performance, covers the surface of a nickel substrate with a dense nanofiber mesh and extends the dense nanofiber mesh through the internal pores of the nickel substrate. This allows the dense nanofiber mesh to be uniformly and tightly distributed on the surface of the nickel substrate, so that it has good hydrophobicity. Compared with nickel substrates without dense nanofiber mesh coverage, the nickel composite material has better sound absorption performance, damping performance and mechanical properties.
[0007] Another aspect of this application provides a method for preparing the aforementioned nickel composite material suitable for improving vibration reduction and noise reduction performance, which includes the following steps: S10: preparing a spinning solution; S20: heating and stirring the solution obtained in step S10 in a water bath; S30: removing undissolved solid particles and impurities from the solution obtained in step S20; S40: spinning the solution onto the surface of a nickel substrate through a spinning process to obtain a nickel composite material; wherein, in step S40, the needle extrusion speed, spinning voltage, and distance between the needle and the spinning plate are set to enable the nickel composite material to obtain a predetermined sound absorption coefficient within a predetermined time.
[0008] The aforementioned method for preparing nickel composite materials suitable for improving vibration reduction and noise reduction performance, provided in the embodiments of this application, allows for better control of fiber diameter, uniformity, porosity, fiber web thickness, areal density, and coverage uniformity by setting the needle extrusion speed, spinning voltage, and distance between the needle and the spinning plate. This enables precise control of the microstructure of the fiber web and, consequently, the improvement in sound absorption coefficient. By controlling the spinning voltage and the distance between the needle and the spinning plate, fibers can be uniformly coated on the surface of the nickel substrate and embedded in the pores, forming a strong interfacial bond. By setting predetermined spinning time and predetermined spinning parameters, batch processing of the nickel substrate can be achieved, and the deposition thickness of the fiber web can be controlled, thereby improving the production efficiency of nickel composite materials. Attached Figure Description
[0009] To further illustrate the above and other advantages and features of this application, the specific embodiments of this application will be described in more detail below with reference to the accompanying drawings. The drawings, together with the following detailed description, are included in and form a part of this specification. Elements having the same function and structure are indicated by the same reference numerals. It should be understood that these drawings only depict typical examples of this application and should not be considered as limiting the scope of this application.
[0010] Figure 1 This is a schematic diagram of a nickel-based substrate. Figure 2 This is a schematic diagram of the structure of the nickel composite material provided in the embodiments of this application; Figure 3 This is a schematic diagram showing the relationship between the sound absorption coefficient and frequency of the nickel composite material prepared by the preparation method provided in the embodiments of this application; Figure 4 This is a schematic diagram comparing the noise reduction coefficients of the nickel composite material prepared by the preparation method provided in the embodiments of this application with those of a nickel substrate of the same thickness; Figure 5 This is a schematic diagram comparing the stress and strain of nickel composite materials and nickel substrates prepared by the preparation method provided in the embodiments of this application at different spinning times; Figure 6This is a schematic diagram comparing the impact acceleration versus time of the nickel composite material and the nickel substrate obtained by the preparation method provided in the embodiments of this application. Detailed Implementation
[0011] Exemplary embodiments of this application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the development of any such actual embodiment to achieve the developer's specific goals, such as complying with constraints related to the system and business, and these constraints may vary depending on the implementation. Furthermore, it should be understood that while development work can be very complex and time-consuming, such development work is merely a routine task for those skilled in the art who benefit from the content of this application.
[0012] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the equipment structure and / or processing steps closely related to the solution according to this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.
[0013] The following disclosure provides several different implementations or examples for carrying out this application. To simplify the disclosure of this application, specific examples of components and methods are described below. Of course, these are merely examples and are not intended to limit this application. In the description of the embodiments of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0014] One embodiment of this application provides a nickel composite material suitable for improving vibration reduction and noise reduction performance, comprising: a nickel substrate with a foam-like porous structure, and a dense nanofiber mesh composed of a spinnable polymer covering the surface of the nickel substrate, the dense nanofiber mesh extending through the internal pores of the nickel substrate.
[0015] The nickel composite material provided in the embodiments of this application, which is suitable for improving vibration reduction and noise reduction performance, covers the surface of a nickel substrate with a dense nanofiber mesh and extends the dense nanofiber mesh through the internal pores of the nickel substrate. This allows the dense nanofiber mesh to be uniformly and tightly distributed on the surface of the nickel substrate, so that it has good hydrophobicity. Compared with nickel substrates without dense nanofiber mesh coverage, the nickel composite material has better sound absorption performance, damping performance and mechanical properties.
[0016] Figure 1 This is a schematic diagram of a nickel-based substrate. Figure 2 This is a schematic diagram of the structure of the nickel composite material obtained by preparing a nickel substrate according to the embodiments of this application. In some embodiments, such as Figure 1and Figure 2 As shown, in the case of Figure 1 After the nickel substrate is coated with a dense nanofiber mesh, the dense nanofiber mesh can be tightly distributed in the nickel-based material, and the dense nanofiber mesh extends through the material. Figure 1 Internal pores of the medium-nickel substrate.
[0017] In some embodiments, the spinnable polymer is one or more of polyacrylonitrile (PAN), thermoplastic polyurethane (TPU), polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyethylene terephthalate (PET), polyvinyl alcohol (PVA), polylactic acid (PLA), and polymethyl methacrylate (PMMA). These polymers, as mature spinnable polymers, exhibit good solubility in common solvents, and their solution viscosity and conductivity are easily controlled, enabling the stable spinning of bead-free, continuous nanofibers, which is beneficial for forming high-porosity sound-absorbing / damping structures. Furthermore, these polymers have good compatibility with nickel substrates, and their polar groups readily form hydrogen bonds / coordinate bonds with the nickel surface oxide layer, resulting in strong adhesion without the need for complex pretreatment.
[0018] Another embodiment of this application provides a method for preparing the aforementioned nickel composite material suitable for improving vibration reduction and noise reduction performance, which includes the following steps: S10: preparing a spinning solution; S20: heating and stirring the solution obtained in step S10 in a water bath; S30: removing undissolved solid particles and impurities from the solution obtained in step S20; S40: spinning the solution onto the surface of a nickel substrate through a spinning process to obtain a nickel composite material; wherein, in step S40, the needle extrusion speed, spinning voltage, and distance between the needle and the spinning plate are set to enable the nickel composite material to obtain a predetermined sound absorption coefficient within a predetermined time.
[0019] The aforementioned method for preparing nickel composite materials suitable for improving vibration reduction and noise reduction performance, provided in the embodiments of this application, allows for better control of fiber diameter, uniformity, porosity, fiber web thickness, areal density, and coverage uniformity by setting the needle extrusion speed, spinning voltage, and distance between the needle and the spinning plate. This enables precise control of the microstructure of the fiber web and, consequently, the improvement in sound absorption coefficient. By controlling the spinning voltage and the distance between the needle and the spinning plate, fibers can be uniformly coated on the surface of the nickel substrate and embedded in the pores, forming a strong interfacial bond. By setting predetermined spinning time and predetermined spinning parameters, batch processing of the nickel substrate can be achieved, and the deposition thickness of the fiber web can be controlled, thereby improving the production efficiency of nickel composite materials.
[0020] In some embodiments, in step S10, the composition of the solution is set as follows: the solute is 12-18 wt% polyacrylonitrile, and the solvent is 82-88 wt% N,N-dimethylformamide (DMF); or the solute is 22-28 wt% thermoplastic polyurethane, and the solvent is 72-78 wt% N,N-dimethylformamide and acetone, wherein the mass ratio of N,N-dimethylformamide to acetone is 5:8; or the solute is a mixture of 24.2-24.8 wt% thermoplastic polyurethane and 0.2-0.8 wt% polyethylene oxide, and the solvent is 72-78 wt% N,N-dimethylformamide and acetone, wherein the mass ratio of N,N-dimethylformamide to acetone is 5:8. The spinning solution formulated with the above-mentioned components can produce fibers with better morphology and significantly improve the sound absorption coefficient. The components allow for precise matching of the solution's viscosity, conductivity, and surface tension. DMF provides polarity and solubility, while acetone regulates volatility and fluidity. This enables stable and continuous spraying of the Taylor cone, preventing fiber breakage and needle blockage during subsequent spinning processes. It also allows for precise deposition of predetermined fiber areal density and thickness within a fixed spinning time (0.5-2 min), making the spinning process more stable and repeatable.
[0021] The classic solvent system of polyacrylonitrile (PAN) and DMF can make the solution have moderate viscosity and conductivity, which makes it easy to obtain continuous, beadless, uniform fibers with a diameter in the range of 100-500nm in subsequent spinning steps. PAN / DMF is often used for sound absorption, and the fibers have a very large specific surface area.
[0022] By setting the mass ratio of DMF to acetone to 5:8, the solution viscosity can be significantly reduced and the evaporation can be accelerated, which is conducive to the formation of a smooth, dense fiber network with a porosity of >85-95%. Furthermore, DMF can ensure the complete dissolution of thermoplastic polyurethane (TPU) and the stability of the Taylor cone.
[0023] Polyethylene oxide (PEO) can be used as a spinning aid to further improve the conductivity of the solution and reduce its viscosity, which is beneficial for obtaining finer and more uniform fibers. At the same time, it imparts a certain degree of hydrophilicity to assist the entry of sound waves.
[0024] The -CN groups of PAN, the urethane groups of TPU, and the ether bonds of PEO, combined with the high polarity of DMF, enable the formation of strong hydrogen bonds / coordination bonds with the nickel oxide layer. This allows the fibers to uniformly coat and embed themselves in the porous structure of nickel without clogging the substrate pores. The elasticity of TPU or a mixture of TPU and PEO enhances vibration damping. Simultaneously, the fibers can increase the tensile strength from approximately 2.3 MPa for pure nickel to 3.6 MPa. Through these configurations, the interfacial bonding between the fiber web and the nickel substrate is strengthened, resulting in enhanced damping and mechanical properties.
[0025] In some embodiments, in step S40, the spinning process can be set to electrospinning. By electrospinning the nickel composite material made of the above-mentioned polymer, the mid-to-low frequency sound absorption performance, vibration damping performance, and mechanical properties of the nickel composite material can be improved, and it can be made lightweight, flexible, and durable.
[0026] Figure 3 This is a schematic diagram showing the relationship between the sound absorption coefficient and frequency of the nickel composite material prepared by the preparation method provided in the embodiments of this application. In some embodiments, such as... Figure 3 As shown in the figure, the dotted lines represent the sound absorption coefficient of the nickel substrate as a function of frequency. The nickel substrate has a low sound absorption coefficient and poor sound absorption performance. The triangular lines represent the sound absorption coefficient of the nickel composite material obtained with a spinning time of 0.5 min as a function of frequency, the square lines represent the sound absorption coefficient of the nickel composite material obtained with a spinning time of 1 min as a function of frequency, and the diamond lines represent the sound absorption coefficient of the nickel composite material obtained with a spinning time of 2 min as a function of frequency. This shows that the sound absorption capacity of the nickel substrate is greatly improved after spinning, and the longer the spinning time, the more obvious the improvement in low and mid-frequency sound absorption. This proves that electrospun nanofiber mesh can improve the sound absorption performance of metal-based porous materials, and the spinning time parameter has a significant impact on optimizing low and mid-frequency sound absorption.
[0027] Figure 4 This is a schematic diagram comparing the noise reduction coefficients of the nickel composite material prepared by the preparation method provided in the embodiments of this application with those of a nickel substrate of the same thickness. In some embodiments, such as Figure 4 As shown in the bar chart, bars of the same color represent nickel substrate and nickel composite material with the same thickness. For the same thickness, bars with lower noise reduction coefficient values correspond to nickel substrate, while higher values correspond to nickel composite material obtained by spinning for 2 minutes. Figure 4 It can be shown that, with the same thickness of nickel substrate and nickel composite material, the noise reduction coefficient (NRC) of nickel composite material treated by spinning for 2 minutes is significantly improved, and the improvement in noise reduction coefficient is greater with increasing thickness (e.g., Figure 4 When the thickness is 12-16mm, the noise reduction coefficient reaches 0.19. Since the noise reduction coefficient reflects the low-frequency sound absorption performance of the material, Figure 4 This demonstrates that nickel composite materials can achieve lightweight properties and good low-frequency sound absorption performance.
[0028] Figure 5 This is a schematic diagram comparing the stress and strain of nickel composite materials and nickel substrates prepared by the preparation method provided in the embodiments of this application at different spinning times. In some embodiments, such as Figure 5As shown in the figure, the line connecting the dots represents the stress-strain curve of the nickel substrate, the line connecting the triangles represents the stress-strain curve of the nickel composite material obtained with a spinning time of 0.5 min, the line connecting the squares represents the stress-strain curve of the nickel composite material obtained with a spinning time of 1 min, and the line connecting the diamonds represents the stress-strain curve of the nickel composite material obtained with a spinning time of 2 min. It can be seen that electrospun nanofiber webs on the surface of the nickel substrate can improve the tensile strength of the material, and the nickel composite material obtained with a spinning time of 1 min has the highest tensile strength. This indicates that the optimal spinning time in this embodiment is 1 min. If the spinning time is too long, the tensile properties will slightly decrease, while the ductility of the material will not be affected.
[0029] Figure 6 This is a schematic diagram comparing the impact acceleration versus time of the nickel composite material and the nickel substrate obtained by the preparation method provided in the embodiments of this application. In some embodiments, such as Figure 6 As shown in the figure, the red dashed line represents the impact acceleration of the nickel substrate as a function of time, and the purple line represents the impact acceleration of the nickel composite material obtained by spinning for 2 minutes as a function of time. After electrospinning a fiber web on the surface of the nickel substrate for 2 minutes, the impact acceleration oscillation of the nickel composite material decays rapidly, and the decay time is shortened from >0.2s to <0.1s. The residual vibration almost disappears, indicating that the vibration damping performance of the material is significantly enhanced. This proves that the electrospun fiber web can effectively improve the transient vibration suppression capability of the metal substrate.
[0030] In some embodiments, in step S40, the predetermined time, needle extrusion speed, spinning voltage, and distance between the needle and the spinning plate conform to the following relationship: ;in, Fiber areal density, For the scheduled time, The speed at which the needle is squeezed. The spinning voltage, This is the distance between the needle and the spinning plate. This represents the mass fraction of the solution. This is a reference voltage for the spinning voltage, with a value ranging from 18-22kV. The reference distance between the needle and the spinning plate is 12-18cm. By using the above method, a more accurate fiber areal density can be obtained, and the predetermined sound absorption coefficient can be improved within the predetermined spinning time. This improves material utilization and the lightweight effect of the material, avoiding material waste or insufficient performance.
[0031] In some embodiments, the sound absorption coefficient is determined as follows: the target acoustic frequency of the nickel composite material in the applicable scenario is determined; the dynamic viscosity of the air in the applicable scenario of the nickel composite material is determined; the viscous boundary layer thickness in the applicable scenario of the nickel composite material is determined; multiple measurement positions are selected on the surface of the prepared nickel composite material, and each position is cut into a sample of a predetermined size; the average fiber diameter and nanofiber layer porosity of the nanofiber mesh of the sample of the predetermined size are determined; the effective pore area factor of the nickel composite material is determined; and the sound absorption coefficient is determined based on the target acoustic frequency, dynamic viscosity of air, viscous boundary layer thickness, nanofiber layer porosity, average fiber diameter, effective pore area factor, and fiber areal density.
[0032] By selecting multiple measurement locations, cutting samples, and measuring the average fiber diameter and nanofiber layer porosity, the non-uniformity of the nickel substrate surface is fully considered, reducing the deposition differences caused by the uneven pore distribution of porous nickel foam, improving the uniformity and consistency of nickel composite materials, and helping to improve the performance stability between batches in mass production.
[0033] In some embodiments, the improvement of sound absorption coefficient, target sound frequency, air dynamic viscosity, viscous boundary layer thickness, nanofiber layer porosity, average fiber diameter, effective pore area factor, and fiber areal density conforms to the following relationship: ;in, To improve the sound absorption coefficient, Fiber areal density, For the target sound wave frequency, The dynamic viscosity of air. The thickness of the viscous boundary layer. The average fiber diameter, The porosity of the nanofiber layer, The effective pore area factor of nickel composite materials is used to accurately determine the sound absorption coefficient of nickel composite materials through the above method, thereby improving the design efficiency of materials and enabling them to be extended to different application scenarios.
[0034] In some embodiments, the target acoustic frequency is determined as follows: the maximum frequency value of the target acoustic frequency range targeted by the nickel composite material in the applicable scenario is determined. Determine the minimum frequency value of the target acoustic frequency range for the nickel composite material in the applicable scenario. Based on the maximum and minimum frequency values, the target acoustic frequency for the nickel composite material in the applicable scenario is determined. By determining the target acoustic frequency according to the maximum and minimum frequency values of the target acoustic frequency range in the applicable scenario, the corresponding viscous boundary layer thickness range can be accurately determined, thereby obtaining the optimal fiber areal density / porosity. This avoids selecting a single high frequency, which may lead to low-frequency path blockage, or selecting a low frequency, which may lead to high-frequency sound leakage, resulting in a high degree of adaptability to different application scenarios.
[0035] In some embodiments, the maximum frequency value, the minimum frequency value, and the target acoustic frequency of the nickel composite material in the applicable scenario conform to the following relationship: ;in, The maximum frequency value, The minimum frequency value, This refers to the target acoustic frequency of the nickel composite material in its applicable scenarios.
[0036] In porous / fiber materials, the sound absorption peak or effective dissipation region is often related to the logarithmic scale of frequency, and the dissipation capacity changes logarithmically with frequency. By determining the target sound wave frequency through the geometric mean method described above, it can be aligned with the center of the logarithmic frequency scale. After optimizing the fiber spacing / pore size, the peak window of viscous friction and heat dissipation uniformly covers the entire target range, rather than being biased to one end. This conforms to the physical nature of acoustic dissipation mechanisms and achieves optimal alignment of broadband sound absorption peaks. Furthermore, the geometric mean can lower the center frequency compared to the arithmetic mean, making the optimization more biased towards lower frequencies. This is more suitable for scenarios with long low-frequency wavelengths, thick boundary layers, and the need for larger dissipation paths (e.g., automotive cabins, building sound insulation, and industrial equipment), thus compensating for the shortcomings of metal substrates.
[0037] In some embodiments, the dynamic viscosity of air can be determined as follows: determine the experimental temperature for testing the nickel composite material in the applicable scenario; determine a reference temperature based on the experimental temperature; determine a reference dynamic viscosity at the reference temperature; and determine the dynamic viscosity of air based on the reference dynamic viscosity. This eliminates calculation errors caused by temperature fluctuations, thereby accurately determining the thickness of the viscous boundary layer and improving the accuracy of increasing the sound absorption coefficient.
[0038] In some embodiments, the experimental temperature, reference temperature, reference dynamic viscosity, and air dynamic viscosity conform to the following relationship: ;in, The experimental temperature, For reference temperature, For reference dynamic viscosity, The dynamic viscosity of air. is Sutherland's constant. This term can reflect the change in average molecular kinetic energy with increasing temperature. This method can correct intermolecular attraction and, combined with the Sutherland constant, which characterizes the temperature dependence of the effective collision diameter, can perform reliable temperature-dependent corrections, thereby improving the accuracy of air dynamic viscosity.
[0039] In some embodiments, the viscous boundary layer thickness is determined by: determining the dynamic viscosity of air for the applicable scenario of the nickel composite material; determining the standard air density; determining the angular frequency of the measuring device; and determining the viscous boundary layer thickness based on the dynamic viscosity of air, the standard air density, and the angular frequency. This method enables a more accurate match between the viscous boundary layer thickness and the actual sound wave dissipation mechanism.
[0040] In some embodiments, the dynamic viscosity of air, standard air density, angular frequency, and viscous boundary layer thickness conform to the following relationship: ;in, The dynamic viscosity of air. Standard air density, Angular frequency, The thickness of the viscous boundary layer is related to the inverse square root of the angular frequency. At low frequencies, the viscous boundary layer is thicker, requiring a larger pore / sparser fiber network to capture the dissipative layer of long-wavelength sound waves. At high frequencies, the viscous boundary layer is thinner, requiring finer fibers to match the thinner boundary layer. This allows for targeted optimization at different frequencies to maximize the sound absorption performance in the mid and low frequencies.
[0041] In some embodiments, the effective pore area factor of the nickel composite material can be determined as follows: determining the porosity of the nickel substrate; determining the pore coverage of the nickel composite material surface; and determining the effective pore area factor of the nickel composite material based on the porosity of the nickel substrate and the pore coverage of the nickel composite material surface. Determining the effective pore area factor in this way more accurately reflects the actual pore area that sound waves can enter or dissipate, further improving the accuracy of increasing the sound absorption coefficient.
[0042] In some embodiments, the porosity of the nickel substrate, the pore coverage of the nickel composite material surface, and the effective pore area factor of the nickel composite material conform to the following relationship: ;in, Porosity of nickel substrate The surface pore coverage of the nickel composite material, This represents the effective pore area factor for nickel composites. By distinguishing between the original porosity of the nickel substrate (the ratio of the volume of interconnected pores inside the substrate to the total volume; the original porosity of nickel foam substrates is typically 70–90%) and the surface pore coverage (the proportion of exposed / unblocked pores on the substrate surface after electrospun fiber web coverage, typically <100%, depending on spinning time / density), it quantifies and corrects the effective pore area (rather than the nominal total pores) that allows acoustic waves to truly penetrate and generate viscosity or heat dissipation within the nickel composite. This ensures that the optimized fiber density just partially penetrates or bridges the pores without completely blocking them.
[0043] Regarding the embodiments of this application, it should also be noted that, without conflict, the embodiments of this application and the features in the embodiments can be combined with each other to obtain new embodiments.
[0044] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. The scope of protection of this application shall be determined by the scope of the claims.
Claims
1. A nickel composite material suitable for improving vibration reduction and noise reduction performance, characterized in that, It includes: Nickel substrate with a foam-like porous structure, The nickel substrate surface is covered with a dense nanofiber web composed of spinnable polymer. The dense nanofiber mesh extends through the internal pores of the nickel substrate.
2. The nickel composite material according to claim 1, characterized in that, The spinnable polymer is one or more of the following: polyacrylonitrile, thermoplastic polyurethane, polyethylene oxide, polyvinylidene fluoride, polyethylene terephthalate, polyvinyl alcohol, polylactic acid, and polymethyl methacrylate.
3. A method for preparing the nickel composite material as described in claim 1 or 2, suitable for improving vibration reduction and noise reduction performance, characterized in that, It includes the following steps: S10: Prepare the spinning solution; S20: Heat the solution obtained in step S10 in a water bath and stir; S30: Remove undissolved solid particles and impurities from the solution obtained in step S20; S40: The solution is spun onto the surface of the nickel substrate by a spinning process to obtain the nickel composite material; In step S40, the needle extrusion speed, spinning voltage, and distance between the needle and the spinning plate are set to enable the nickel composite material to achieve a predetermined increase in sound absorption coefficient within a predetermined time.
4. The method according to claim 3, characterized in that: In step S10, the composition of the solution is set as follows: The solute is 12-18 wt% polyacrylonitrile, and the solvent is 82-88 wt% N,N-dimethylformamide; Alternatively, the solute may be 22-28 wt% thermoplastic polyurethane, and the solvent may be 72-78 wt% N,N-dimethylformamide and acetone, wherein the mass ratio of N,N-dimethylformamide to acetone is 5:
8. Alternatively, the solute may be a mixture of 24.2-24.8 wt% thermoplastic polyurethane and 0.2-0.8 wt% polyethylene oxide, and the solvent may be 72-78 wt% N,N-dimethylformamide and acetone, wherein the mass ratio of N,N-dimethylformamide to acetone is 5:
8.
5. The method according to claim 3, characterized in that, In step S40, The predetermined time, the needle extrusion speed, the spinning voltage, and the distance between the needle and the spinning plate conform to the following relationship: ； in, Fiber areal density, For the predetermined time, The needle extrusion speed, The spinning voltage, The distance between the needle and the spinning plate. This represents the mass fraction of the solution. The reference voltage for the spinning voltage is 18-22kV. The reference distance between the needle and the spinning plate is 12-18cm.
6. The method according to claim 5, characterized in that, The improved sound absorption coefficient is determined using the following method: Determine the target acoustic frequency of the nickel composite material in the applicable scenario; Determine the dynamic air viscosity for the applicable scenarios of the nickel composite material; Determine the viscous boundary layer thickness for the applicable scenarios of the nickel composite material; Multiple measurement locations were selected on the surface of the prepared nickel composite material, and each location was cut into a sample of a predetermined size; Determine the average fiber diameter and nanofiber layer porosity of the nanofiber mesh of the sample of the predetermined size; Determine the effective pore area factor of nickel composite materials; The enhanced sound absorption coefficient is determined based on the target sound wave frequency, the dynamic viscosity of air, the thickness of the viscous boundary layer, the porosity of the nanofiber layer, the average fiber diameter, the effective pore area factor, and the fiber surface density.
7. The method according to claim 6, characterized in that, The improved sound absorption coefficient, the target sound wave frequency, the air dynamic viscosity, the viscous boundary layer thickness, the nanofiber layer porosity, the average fiber diameter, the effective pore area factor, and the fiber areal density conform to the following relationship: ； in, To improve the sound absorption coefficient, The fiber areal density, The target sound wave frequency, The dynamic viscosity of air. The thickness of the viscous boundary layer is [missing information]. The average fiber diameter is... The porosity of the nanofiber layer is... The effective pore area factor of the nickel composite material is given.
8. The method according to claim 6, characterized in that, The target acoustic wave frequency is determined as follows: Determine the maximum frequency value of the target acoustic frequency range for the nickel composite material in the applicable scenario. ; Determine the minimum frequency value of the target acoustic frequency range for the nickel composite material in the applicable scenario. ; Based on the maximum frequency value and the minimum frequency value, the target acoustic frequency of the nickel composite material in the applicable scenario is determined.
9. The method according to claim 8, characterized in that, The maximum frequency value, the minimum frequency value, and the target acoustic frequency of the nickel composite material in the applicable scenario conform to the following relationship: ； in, The maximum frequency value, The minimum frequency value, The target acoustic frequency of the nickel composite material in the applicable scenario.
10. The method according to claim 6, characterized in that, The dynamic viscosity of air was determined as follows: Determine the experimental temperature for conducting experiments on the nickel composite material in the applicable scenario; Determine the reference temperature based on the experimental temperature; Determine the reference dynamic viscosity at the reference temperature; The air dynamic viscosity is determined based on the reference dynamic viscosity.
11. The method according to claim 10, characterized in that, The experimental temperature, the reference temperature, the reference dynamic viscosity, and the air dynamic viscosity conform to the following relationship: ； in, The experimental temperature is [temperature value missing]. The reference temperature is... The reference dynamic viscosity, The dynamic viscosity is... is Sutherland's constant.
12. The method according to claim 6, characterized in that, The thickness of the viscous boundary layer is determined as follows: Determine the dynamic air viscosity for the applicable scenarios of the nickel composite material; Determine the standard air density; Determine the angular frequency of the device used for measurement; The thickness of the viscous boundary layer is determined based on the dynamic viscosity of the air, the standard air density, and the angular frequency.
13. The method according to claim 12, characterized in that, The dynamic viscosity of air, the standard air density, the angular frequency, and the viscous boundary layer thickness conform to the following relationship: ； in, The dynamic viscosity of air. The standard air density is... The angular frequency is... The thickness of the viscous boundary layer is given.
14. The method according to claim 6, characterized in that, The effective pore area factor of the nickel composite material was determined as follows: Determine the porosity of the nickel substrate; Determine the surface pore coverage of the nickel composite material; The effective pore area factor of the nickel composite material is determined based on the porosity of the nickel substrate and the pore coverage of the nickel composite material surface.
15. The method according to claim 14, characterized in that, The porosity of the nickel substrate, the pore coverage of the nickel composite material surface, and the effective pore area factor of the nickel composite material conform to the following relationship: ； in, The porosity of the nickel substrate is... The surface pore coverage of the nickel composite material. The effective pore area factor of the nickel composite material is given.