Carbon fiber reinforced polymer surface pure aluminum powder cold spraying deposition method

Abstract

The invention provides a carbon fiber reinforced polymer surface pure aluminum powder cold spraying deposition method. The method belongs to the field of nonmetal material surface metallization and comprises the steps that S1, the surface of a carbon fiber reinforced polymer is cleaned, it is guaranteed that the surface of the carbon fiber reinforced polymer is smooth and clean, and adhesion of a coating is facilitated; s2, spraying aluminum powder on the surface of the carbon fiber reinforced polymer by using a cold spraying technology; and S3, the deposited aluminum powder is subjected to curing treatment, so that firm combination of the coating and the matrix is ensured, and the heat conduction performance and the corrosion resistance of the carbon fiber reinforced polymer are effectively improved through the pure aluminum coating. The method has the advantages that the plasma surface cleaning technology is adopted for cleaning the surface of the carbon fiber reinforced polymer, and deposition of metal powder is better facilitated; the shot blasting treatment has a very obvious effect on an aluminum powder deposition carbon fiber reinforced polymer matrix; and the adopted deposition particles are pure aluminum powder, and the selected spraying gas is N2, so that the cost is low, and the deposition particles are easy to purchase.

Description

Technical Field

[0001] The invention provides a method for cold spraying and depositing pure aluminum powder on the surface of a carbon fiber reinforced polymer, and relates to the field of surface metallization of non-metallic materials. Background Art

[0002] Carbon fiber reinforced polymer is a lightweight, high-strength composite material with a wide range of applications in aerospace, automobiles, sports equipment and other fields. However, due to its low thermal conductivity and mechanical properties, its application is subject to certain limitations.

[0003] In order to improve the thermal conductivity and wear resistance of carbon fiber reinforced polymers, metal coatings can be applied on their surfaces. Metal coatings can improve the thermal conductivity of carbon fiber reinforced polymers, increase their strength and hardness, and improve their wear resistance and corrosion resistance, thereby expanding the application range of carbon fiber reinforced polymers in aerospace, automobiles, energy and other fields. Therefore, the technology of applying metal coatings is of great significance for improving the performance of carbon fiber reinforced polymers and expanding their application fields.

[0004] At present, there are many commonly used methods for surface metallization of carbon fiber reinforced polymer substrates, such as vacuum evaporation, vacuum ion plating, electroplating, chemical plating, electroforming, and direct surface metal spraying. These methods have their own advantages and disadvantages: for example, the coating thickness of vacuum evaporation and vacuum ion plating is uniform, but the required equipment is expensive and the size of the product is limited by the size of the equipment, the coating is thin and the preparation cost is high. The electroplating process is complicated and the coating adhesion is relatively low; chemical plating is a must in most electroplating processes, usually as a pre-treatment process for electroplating of plastic products, its advantages are dense coating, low porosity, a wide range of applicable substrate materials, and can be deposited on metals, inorganic non-metals and organic matter; the disadvantages are short plating solution life, poor stability, slow plating speed, difficulty in preparing thick coatings, and environmental pollution. Electroforming can produce parts with high finish, high conductivity, high precision, and complex inner cavity structure, but each part requires a mold, the mold cost is high, and the production cycle is long. Thermal spraying is a method of heating metal particles to a molten state and then depositing them onto the surface of a substrate or workpiece to form a coating. However, the melting point of polymer substrate materials is very low. During thermal spraying, molten metal particles and high-temperature flame flow will cause serious damage to the surface of the polymer substrate material. In addition, due to the high heating temperature of thermal spraying, the prepared metal coating is difficult to meet the use requirements due to oxidation and the generation of pores.

[0005] In recent years, cold spray technology has emerged as a new material surface modification technology and additive manufacturing technology that has attracted much attention. Cold spray refers to a spraying technology that uses supersonic airflow to spray solid powder onto the surface of a workpiece to form a dense coating at a low temperature or room temperature. It has significant advantages such as economic and environmental protection, energy saving and consumption reduction, safety and efficiency, and easy operation. Therefore, metal powder cold spray deposition technology is considered to be an effective method to enhance the performance of carbon fiber reinforced polymer materials. Summary of the invention

[0006] The purpose of the present invention is to provide a method for cold spraying and depositing pure aluminum powder on the surface of a carbon fiber reinforced polymer, so as to achieve surface metallization of the carbon fiber reinforced polymer and improve the thermal conductivity and corrosion resistance of the carbon fiber reinforced polymer material.

[0007] In order to achieve the above objectives, the present invention provides a method for cold spraying and depositing metal powder on the surface of a carbon fiber reinforced polymer, comprising the following steps:

[0008] S1. Clean the surface of the carbon fiber reinforced polymer to ensure that the surface of the carbon fiber reinforced polymer is smooth and clean, which is conducive to the adhesion of the coating;

[0009] S2. Use cold spraying technology to spray aluminum powder on the surface of carbon fiber reinforced polymer. During the cold spraying process, pure aluminum powder enters the accelerating airflow through the powder feeding gas N2, is accelerated to supersonic speed by the high-speed airflow, impacts and adheres to the surface of the substrate, and forms a uniform metal coating.

[0010] S3. The deposited aluminum powder is cured to ensure a firm bond between the coating and the substrate and to improve its thermal conductivity and corrosion resistance.

[0011] Preferably, the carbon fiber reinforced polymer is a composite material of carbon fiber reinforced epoxy resin. Epoxy resin is an adhesive, so there is no need to coat the adhesive on the surface of the substrate.

[0012] Preferably, the volume fraction of carbon fiber in the carbon fiber reinforced polymer is 50-57%.

[0013] Preferably, in step S1, the surface of the carbon fiber reinforced polymer is cleaned using plasma surface cleaning technology, which effectively solves the problems of rough surface caused by grinding, difficult operation and distance and time control of the flame method, and damage to the material by the chemical reagent wiping method.

[0014] Preferably, in step S2, the main technical parameters adopted in the cold spraying process are: aluminum powder particle size: 15-40μm; spraying distance: 180-220mm; spraying pressure: 1.6-1.8MPa; spraying temperature: 330-370℃; powder feeding speed: 0.5-0.9g / s; and spraying thickness is 0.5-1.0mm.

[0015] Preferably, in step S3, the deposited aluminum powder is solidified. Since it is difficult for pure aluminum powder to be deposited on the surface of carbon fiber reinforced polymer, it is necessary to perform solidification to ensure that the coating is firmly bonded to the substrate and improve its thermal conductivity and corrosion resistance. Preferably, the solidification method is mainly shot peening, that is, copper particles or stainless steel particles with a larger particle size (greater than 40 μm) are used as spraying particles, and the coating is impacted at a relatively low speed (the spraying speed of the spraying particles is 500-600 m / s) to achieve a firm coating effect without copper particles being deposited on the substrate. Since the deposition process involved in the present invention has a relatively small spraying thickness, and the coating is pure aluminum powder, which is a soft material, shot peening is very effective for aluminum powder deposition on a carbon fiber reinforced polymer substrate.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The difficulty of this technology is that the substrate is a carbon fiber reinforced polymer, which has high hardness, high elasticity and poor deformation ability at room temperature. When sprayed at room temperature, it is difficult for particles to deposit on the substrate, which mainly causes erosion of the substrate. This organic substrate material will soften as the temperature rises, and the impact of high-speed sprayed particles will easily cause serious distortion of the substrate surface, making it difficult to ensure the coating quality. Therefore, the present invention uses cold spraying technology to effectively overcome the above difficulties.

[0018] The present invention uses plasma surface cleaning technology to clean the surface of carbon fiber reinforced polymer, overcoming the problems of rough surface caused by grinding, difficult operation and distance and time control of flame method, and material damage caused by chemical reagent wiping method.

[0019] The carbon fiber reinforced polymer involved in the present invention is a carbon fiber reinforced epoxy resin composite material. The epoxy resin is an adhesive, so there is no need to coat the adhesive on the surface of the substrate.

[0020] Since the spraying thickness of the deposition process involved in the present invention is relatively small and the coating is pure aluminum powder, which is a soft material, shot peening is very effective in depositing the carbon fiber reinforced polymer matrix on aluminum powder.

[0021] The present invention performs cold spraying on a carbon fiber reinforced polymer matrix. The deposited particles used are pure aluminum powders and the spraying gas selected is N2, which is low in cost and easy to purchase. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is the technical roadmap of the present invention. DETAILED DESCRIPTION

[0023] The following non-limiting embodiments may enable a person skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0024] Example 1

[0025] The method for cold spraying and depositing pure aluminum powder on the surface of a carbon fiber reinforced polymer according to the present invention comprises the following steps:

[0026] S1: The carbon fiber in the carbon fiber reinforced polymer is Toray T700s, and the polymer matrix uses epoxy resin with model CAS No. 25085-99-8. The prepreg of the carbon fiber reinforced polymer is produced by Tianjin Anglin Maofeng High-tech Materials Co., Ltd., and the volume fraction of the carbon fiber is 50%. The carbon fiber reinforced polymer is prepared by hot pressing molding process. For details, please refer to the literature [Liu Yanpeng, Han Yuze, Ren Zhongjie, Ren Mingfa. Study on tensile and compression failure behavior of ultra-thin single-layer carbon fiber reinforced composite plates [J]. Composite Materials Science and Engineering, 2024.]. Then the surface of the carbon fiber reinforced polymer is cleaned to ensure that the surface of the carbon fiber reinforced polymer is smooth and clean, which is conducive to the adhesion of the coating.

[0027] S2: Aluminum powder is sprayed on the surface of carbon fiber reinforced polymer using cold spraying technology. During the cold spraying process, pure aluminum powder enters the accelerating airflow through the powder feeding gas N2 at a powder feeding speed of 0.5-0.9g / s, is accelerated to supersonic speed by the high-speed airflow, impacts and adheres to the surface of the substrate, and forms a uniform metal coating; wherein, the aluminum powder particle size is 15-40μm, the spraying distance is 200mm, the spraying pressure is 1.7Mpa, the spraying temperature is about 350℃, the spraying thickness is about 0.5mm, and the spraying angle is 90°.

[0028] S3: solidifying the deposited aluminum powder, that is, after the aluminum powder is sprayed, copper particles with a particle size of 45 μm are used as spray particles, and the deposited substrate is solidified at a spraying speed of 600 m / s to ensure that the coating is firmly bonded to the substrate and improve its thermal conductivity and corrosion resistance.

[0029] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A method for cold spraying and depositing pure aluminum powder on the surface of a carbon fiber reinforced polymer, characterized in that: The steps include: S1. Clean the surface of the carbon fiber reinforced polymer to ensure that the surface of the carbon fiber reinforced polymer is smooth and clean; S2, using cold spraying technology to spray aluminum powder on the surface of carbon fiber reinforced polymer to obtain a metal coating; During the cold spraying process, the powder feeding gas is N2; S3. The deposited aluminum powder is solidified.

2. The method for cold spraying and depositing pure aluminum powder on the surface of carbon fiber reinforced polymer according to claim 1, characterized in that: The volume fraction of carbon fiber in the carbon fiber reinforced polymer is 50-57%.

3. The method for cold spraying and depositing pure aluminum powder on the surface of carbon fiber reinforced polymer according to claim 1, characterized in that: The carbon fiber reinforced polymer is a composite material of carbon fiber reinforced epoxy resin.

4. The method for cold spraying and depositing pure aluminum powder on the surface of carbon fiber reinforced polymer according to claim 1, characterized in that: In step S1, the surface of the carbon fiber reinforced polymer is cleaned by plasma surface cleaning technology.

5. The method for cold spraying and depositing pure aluminum powder on the surface of carbon fiber reinforced polymer according to claim 1, characterized in that: In step S2, the main technical parameters used in the cold spraying process are: aluminum powder particle size: 15-40μm; spraying distance: 180-220mm; spraying pressure: 1.6-1.8MPa; spraying temperature: 330-370℃; powder feeding speed: 0.5-0.9g / s; and spraying thickness is 0.5-1.2mm.

6. The method for cold spraying and depositing pure aluminum powder on the surface of carbon fiber reinforced polymer according to claim 1, characterized in that: In step S3, the curing treatment method is mainly shot peening, that is, using spray particles with larger particle sizes to impact the coating.

7. The method for cold spraying and depositing pure aluminum powder on the surface of carbon fiber reinforced polymer according to claim 6, characterized in that: The particle size of the sprayed particles is greater than 40 μm, the sprayed particles are copper particles or stainless steel particles, and the spraying speed of the sprayed particles is 500-600 m / s.

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