阅读说明：本技术 基于冷喷涂与强流脉冲电子束辐照的防护涂层制备方法 (Preparation method of protective coating based on cold spraying and high-current pulse electron beam irradiation ) 是由 解志文 高旭 郭锋 陈永君 燕峰 胡素影 冯博 吴迪 于 2020-07-20 设计创作，主要内容包括：本发明的目的是针对于现有冷喷涂制备防护涂层技术存在的缺陷,提供一种基于冷喷涂与强流脉冲电子束辐照的防护涂层制备方法,属于合金表面处理领域。本发明首先在基体表面设置冷喷涂金属或金属-氧化物复合涂层,再使用HCPEB辐照对涂层表面进行封孔处理。该方法利用HCPEB辐照处理的能量集中、高效率、易控制等特点,对冷喷涂涂层进行表面强化处理,降低涂层表面的孔隙率,实现冷喷涂涂层的表层致密化,从而提高其耐磨防腐蚀性能,具有重要的实际工程应用价值。(The invention aims to overcome the defects of the existing technology for preparing a protective coating by cold spraying, provides a method for preparing the protective coating based on cold spraying and high-current pulse electron beam irradiation, and belongs to the field of alloy surface treatment. The method comprises the steps of firstly arranging a cold spraying metal or metal-oxide composite coating on the surface of a matrix, and then carrying out hole sealing treatment on the surface of the coating by using HCPEB irradiation. The method utilizes the characteristics of energy concentration, high efficiency, easy control and the like of HCPEB irradiation treatment to carry out surface strengthening treatment on the cold spraying coating, reduces the porosity of the surface of the coating and realizes the surface layer densification of the cold spraying coating, thereby improving the wear-resisting and corrosion-resisting properties of the cold spraying coating and having important practical engineering application value.)

1. A method for preparing a protective coating based on cold spraying and high-current pulse electron beam irradiation is characterized in that a cold spraying metal or metal-oxide composite coating is arranged on the surface of a matrix, and then hole sealing treatment is carried out on the surface of the cold spraying coating by HCPEB irradiation.

2. The method for preparing a protective coating based on cold spraying and high current pulsed electron beam irradiation according to claim 1, comprising the following steps:

1) in-situ preparation of cold sprayed metal or metal-oxide composite coating on surface of substrate

a) Preparing a base material: taking a base material, grinding and polishing, removing oil stains and impurities on the surface of a test piece, and then drying a sample after ultrasonic cleaning;

b) sand blasting treatment: SiO for base material before spraying₂Carrying out sand blasting treatment;

c) cold spraying: the coating is prepared by adopting low-pressure supersonic spraying equipment, the temperature of the matrix is not more than 150 ℃, and the cold spraying parameters are as follows: the granularity of the metal or metal-oxide powder is 15-45 μm, the voltage is 210-230V, and the pressure is 0.75-0.85 MPa;

d) polishing and flattening the cold spraying coating;

2) clamping a sample on a target table, putting the sample into a vacuum chamber, and performing HCPEB irradiation treatment on the cold spraying coating; the irradiation technical parameters are as follows: the degree of vacuum pumping is 4-5 x 10^-4Pa, introducing argon gas, 5.0-6.0 × 10^-2Pa, electron beam voltage of the electron gun is 20 kV-30 kV, and energy density is 3J/cm²～9.1J/cm²The pulse number is 30-100, and the working distance is 80-120 mm.

3. The method for preparing a protective coating based on cold spraying and high-current pulsed electron beam irradiation as claimed in claim 1, wherein the cold spraying metal coating is a single-component metal coating or a multi-component alloy coating, and the metal-oxide coating is a single-component metal-oxide coating or a multi-component alloy-oxide coating.

4. The method for preparing a protective coating based on cold spraying and high-current pulsed electron beam irradiation as claimed in claim 1, wherein the thickness of the cold spray coating in step 1) is 50-500 μm.

5. The method for preparing a protective coating based on cold spraying and high-current pulsed electron beam irradiation as claimed in claim 1, wherein the thickness of the coating modified layer obtained by HCPEB irradiation treatment in step 2) is 30-100 μm.

Technical Field

The invention belongs to the field of alloy surface treatment, and particularly relates to a high-current pulse electron beam irradiation modification method of a cold spraying coating.

Background

Cold spraying is a new spraying technology, the temperature of a heat source is far lower than that of hot spraying, solid particles are heated at low temperature, and high-pressure gas (He, Ar and N) is used₂Air or a mixture thereof) is a carrier supersonic spray. Because the temperature in the process of spraying particle deposition is far less than the melting point, the particles are not melted in the whole process, the particles are kept in a solid state, the powder is not seriously melted and changed in phase, the problems of serious oxidation, substrate material damage and the like are not caused in the deposition process, and the prepared coating has better quality, thereby being very suitable for materials sensitive to heat or oxidation, such as magnesium alloy and the like. Most of metal coatings, ceramic coatings and organic coatings can be prepared by the current cold spraying technology, and the applicable field relates to numerous fields such as aerospace, ocean, mechanical engineering and the like.

Although the porosity of the protective coating prepared by the cold spraying technology is obviously lower than that of the thermal spraying coating, a certain amount of pores still exist on the surface and inside of the protective coating due to the limitation of the principle of the spraying technology. In the service process of the protective coating, the pores are easy to become channels for corrosive media to invade into the coating, and are easy to invade by the corrosive media to generate galvanic corrosion, so that the corrosion resistance effect of the protective coating is reduced, and the protective coating fails.

The high-current pulse electron beam (HCPEB) irradiation technology is a new surface modification method in recent years, and high-energy-density electron beams are used for impacting the surface of a material in a vacuum environment and remelting the surface layer of the material at a certain temperature in a very short time, so that the surface properties of the coating material, such as hardness, wear resistance, corrosion resistance and the like, are improved, and the porosity of the coating material is reduced. Compared with other surface modification technologies, HCPEB has the advantages of high energy utilization rate, small material deformation and the like. However, this method is not suitable for treating surfaces of materials sensitive to heat or oxidation.

Disclosure of Invention

The invention aims to overcome the defects of the existing technology for preparing a protective coating by cold spraying, and provides a method for preparing the protective coating based on cold spraying and high-current pulse electron beam irradiation. The method comprises the steps of firstly arranging a cold spraying metal or metal-oxide composite coating on the surface of a matrix, and then carrying out hole sealing treatment on the surface of the coating by using HCPEB irradiation. The method utilizes the characteristics of energy concentration, high efficiency, easy control and the like of HCPEB irradiation treatment to carry out surface strengthening treatment on the cold spraying coating, reduces the porosity of the surface of the coating and realizes the surface layer densification of the cold spraying coating, thereby improving the wear-resisting and corrosion-resisting properties of the cold spraying coating and having important practical engineering application value.

In order to achieve the purpose, the invention provides the following technical scheme:

a method for preparing a protective coating based on cold spraying and high-current pulse electron beam irradiation comprises the steps of firstly arranging a cold spraying metal or metal-oxide composite coating on the surface of a substrate, and then carrying out hole sealing treatment on the surface of the cold spraying coating by using HCPEB irradiation.

Further, the preparation method of the protective coating comprises the following steps:

1) in-situ preparation of cold sprayed metal or metal-oxide composite coating on surface of substrate

a) Preparing a base material: taking a base material, grinding and polishing, removing oil stains and impurities on the surface of a test piece, and then drying a sample after ultrasonic cleaning;

b) sand blasting treatment: SiO for base material before spraying₂Carrying out sand blasting treatment;

c) cold spraying: the coating is prepared by adopting low-pressure supersonic spraying equipment, the temperature of the matrix is not more than 150 ℃, and the cold spraying parameters are as follows: the granularity of the metal or metal-oxide powder is 15-45 μm, the voltage is 210-230V, and the pressure is 0.75-0.85 MPa;

d) polishing and flattening the cold spraying coating;

2) clamping a sample on a target table, putting the sample into a vacuum chamber, and performing HCPEB irradiation treatment on the cold spraying coating; the irradiation technical parameters are as follows: the degree of vacuum pumping is 4-5 x 10^-4pa, introducing argon gas, 5.0-6.0X 10^-2Pa, electron beam voltage of the electron gun is 20 kV-30 kV, and energy density is 3J/cm²～9.1J/cm²The pulse number is 30-100, and the working distance is 80-120 mm.

Further, in the preparation method of the protective coating, the cold spraying metal coating is a single-component metal coating or a multi-component alloy coating, and the metal-oxide coating is a single-component metal-oxide coating or a multi-component alloy-oxide coating.

Further, in the preparation method of the protective coating, in the step 1), the thickness of the cold spray coating is 50-500 μm.

Further, in the preparation method of the protective coating, in the step 2), the thickness of the coating modified layer obtained by HCPEB irradiation treatment is 30-100 μm.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention solves the problems of high porosity and poor wear-resistant and corrosion-resistant performance of cold spraying metal or metal-oxide coatings, and can obviously improve the wear-resistant and corrosion-resistant performance of materials.

2. The coating obtained by the invention has smooth and flat surface, high density, high bonding strength with a matrix and no environmental pollution; the coating preparation steps are simple, economical and practical, and can be used for industrial production.

3. The coating disclosed by the invention has excellent bearing capacity, friction resistance and corrosion resistance, provides a new idea for designing a high-performance protective coating on the surface of the alloy sensitive to heat or oxidation, and has an important promotion effect on engineering application of alloy material parts sensitive to heat or oxidation.

Drawings

FIG. 1, surface topography and cross-sectional topography of the non-irradiated coating.

(a) SEM picture, and (b) optical microscope picture.

FIG. 2, surface topography and cross-sectional topography of the coating after 30 exposures to HCPEB.

(a) SEM picture; (b) optical microscopy images.

Fig. 3 XRD patterns of non-irradiated and irradiated coatings.

FIG. 4 residual stress of the non-irradiated coating and the irradiated coating.

Fig. 5 microhardness of non-irradiated and irradiated coatings.

FIG. 6 shows (a) friction curve and (b) wear track profile profiles for non-irradiated and irradiated coatings.

FIG. 7, wear rates of non-irradiated coating and irradiated coating.

FIG. 8, potential versus dynamic polarization curves for unirradiated and irradiated coatings.

Detailed Description

The examples are provided for the purpose of better illustration of the present invention and are not intended to limit the present invention to the examples. Therefore, those skilled in the art should make insubstantial modifications and adaptations to the embodiments of the present invention in light of the above teachings and remain within the scope of the invention.

The following examples will disclose a method for preparing a protective coating based on cold spray and high current pulsed electron beam irradiation. Preferred embodiments of the present invention will now be described in more complete detail with reference being made to the accompanying drawings.