Method for preparing Al-SiC composite coating through electro-deposition

Abstract

And the Al-SiC composite coating is prepared by using SiC as second-phase particles through an electro-deposition technology. The preparation method comprises the following steps: putting anhydrous AlCl3, LiAlH4 and SiC particles into a glove box filled with argon, weighing 4g of anhydrous AlCl3 and 0.28 g of anhydrous LiAlH4 by using a balance, putting into a beaker, and then weighing a certain amount of SiC particles (20g / L-80g / L) and putting into the beaker; and the beaker is sealed, taken out and put into a fuming cupboard. The method comprises the following steps: measuring 20ml of benzene by using a measuring cylinder, pouring the benzene into a sealed beaker by using a guide tube, and then putting the beaker into a magnetic stirrer under an ice bath condition; 5 ml of tetrahydrofuran is measured and slowly poured into the beaker through the guide tube, and in order to prevent the tetrahydrofuran from deteriorating, the process needs to be carried out under an ice bath condition. And adding tetrahydrofuran, sealing the beaker, stirring for 2-3 hours, and carrying out ultrasonic dispersion for 30 minutes. And an aluminum sheet is used as an anode, a copper sheet is used as a cathode, the current density is controlled to be 30-50 mA / cm < 2 >, the temperature of the plating solution is 20-40 DEG C, the electro-deposition time is 30-75 min, and the Al-SiC composite coating with the compact surface and uniform particle distribution can be obtained, and the Al-SiC composite coating mainly comprises Al and SiC.

Description

Technical Field

[0001] The invention belongs to the field of electrochemical deposition, and in particular relates to a method for preparing a metal composite material Al-SiC composite coating. Background Art

[0002] With the development of modern science and technology, the performance requirements for basic materials are getting higher and higher, especially in the fields of aerospace and military industry. Aluminum and its alloys have excellent properties such as light weight, corrosion resistance, good electrical and thermal conductivity. However, with the continuous improvement of the comprehensive performance requirements of basic materials under modern service conditions, traditional aluminum alloy materials are difficult to meet the requirements. Aluminum-based composites (AMCs) with aluminum and its alloys as the matrix have become an indispensable component of aerospace materials due to their good comprehensive mechanical, physical and chemical properties.

[0003] Aluminum-based composite materials are materials that improve the wear resistance, corrosion resistance, fatigue resistance and other properties of the material by adding second-phase particles to aluminum or aluminum alloys. Some second-phase particles have the advantages of wear resistance, low thermal expansion coefficient and good thermal conductivity. Representative particles include silicon carbide (SiC), yttrium oxide (Y2O3), molybdenum disulfide (MoS2), etc. Silicon carbide particles are a kind of superhard ceramic. The composite material obtained by using them as reinforcement has high strength and good corrosion resistance. At present, there are many methods for preparing aluminum-based composite coating materials, mainly including mechanical alloying method, powder metallurgy method, in-situ synthesis method, etc. These methods have the disadvantages of high equipment cost and complex process. The present invention is a technology for enhancing the material performance by depositing aluminum-second-phase particle coating on the surface of copper substrate by electrochemical deposition. This method has low cost and simple process control compared with other preparation methods. By adding silicon carbide particles to the electrodeposition solution, a composite coating with a high silicon carbide particle content and a relatively uniform distribution of second-phase particles on the surface can be obtained. Summary of the invention

[0004] The purpose of the present invention is to prepare a new aluminum-based composite coating Al-SiC composite coating. The method uses aluminum sheets as anodes, copper as cathodes, and an AlCl3-LiAlH4-benzene-THF organic solvent system with aluminum chloride as the main salt and SiC as reinforcing particles for electrodeposition. The system does not need to add other dispersants. AlCl3 and LiAlH4 can form a stable solvation complex in a mixed solvent of benzene and tetrahydrofuran (THF), and the complex helps to improve the dispersibility of powders in organic solvents. Benzene and THF, as non-polar or weakly polar solvents, can reduce the interaction between powders, thereby improving dispersibility. The addition of silicon carbide particles can refine alloy grains, increase the density of the coating, and thus improve the mechanical properties of the coating. The method has low cost, simple process control, and is convenient for large-scale industrial production.

[0005] The specific embodiments of the present invention are as follows: Preparation of plating solution Place anhydrous AlCl3, LiAlH4 and SiC particles in a glove box, take out the beaker with the rotor and the medicine spoon from the drying box and place them on the tray, then place the tray in the glove box, seal the glove box and fill it with argon. When the argon fills the entire glove box, weigh the drugs. Use a balance to weigh 4g of anhydrous AlCl3 and 0.28g of anhydrous LiAlH4, put them in a beaker, and then measure a certain amount of SiC particles (20g / L~80g / L) and put them in the beaker. Seal the weighed beaker, take it out of the glove box and put it in a fume hood. Use a measuring cylinder to measure 20ml of benzene, pour it into the sealed beaker with a guide tube, and then put the beaker into a magnetic stirrer under ice bath conditions. Measure 5ml of tetrahydrofuran and slowly pour it into the beaker through the guide tube. To prevent tetrahydrofuran from deteriorating, the beaker needs to be placed in an ice bath during this process. After the tetrahydrofuran is completely added, the beaker is sealed, the stirring rate is adjusted to an appropriate value, and the mixture is stirred for 2-3 hours, followed by ultrasonic dispersion for 30 minutes to allow the drug to be fully dissolved and the particles to be evenly dispersed.

[0006] Aluminum substrate treatment The aluminum sheet was polished smooth with 400, 800 and 1200 mesh sandpaper in turn, then chemically degreased to remove oil stains on the surface of the aluminum sheet, and then pre-etched and weakly corroded with dilute hydrochloric acid to remove the oxide film, and then washed with deionized water, and dried in a vacuum drying oven for standby use.

[0007] Copper substrate treatment The copper sheet was polished smooth with 400, 800 and 1200 mesh sandpaper in turn, then chemically degreased to remove oil stains on the surface of the copper sheet, and then pre-etched and weakly corroded with dilute hydrochloric acid to remove the oxide film, and then washed with water, and then placed in a vacuum drying oven to dry for standby use.

[0008] Constant current electrodeposition Using aluminum sheet as anode and copper sheet as cathode, controlling the current density to 30-50 mA / cm2, controlling the plating solution temperature to 20-40°C for electrodeposition, and controlling the electrodeposition time to 30-75 min, an Al-SiC composite coating with a dense surface and uniform particle distribution can be obtained.

[0009] The present invention utilizes the electrodeposition preparation technology with low preparation cost and simple process control, and adopts SiC particles as the second phase particles to prepare the Al-SiC composite coating. The SiC particles provide a large number of nucleation sites to refine the grains and improve the coating morphology. The aluminum-based composite coating has high hardness, wear resistance and corrosion resistance. The problems of high preparation cost and complex operation process of aluminum-based composite materials are solved, and the surface of the obtained Al-SiC composite coating is dense and the SiC particles are evenly distributed. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a SEM image of the composite coating obtained by the present invention; Figure 2 This is an EDS spectrum diagram of the composite coating obtained by the present invention; Figure 3 The XRD spectrum of the composite coating obtained in the present invention is shown in FIG. DETAILED DESCRIPTION

[0011] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0012] The present invention specifically relates to a method for preparing an Al-SiC composite coating by electrodeposition on a copper substrate, which is described in detail below through specific examples. The following examples are only part of the examples of the present invention, not all. Example 1

[0013] (1) Preparation of plating solution Place anhydrous AlCl3, LiAlH4 and SiC particles in a glove box, take out the beaker with the rotor and the medicine spoon from the drying box and place them on the tray, then place the tray in the glove box, seal the glove box and fill it with argon. When the argon fills the entire glove box, weigh the drugs. Use a balance to weigh 4g of anhydrous AlCl3 and 0.28g of anhydrous LiAlH4 and put them in a beaker, then measure a certain amount of SiC particles (40g / L) and put them in the beaker. Seal the weighed beaker, take it out of the glove box and put it in a fume hood. Use a measuring cylinder to measure 20ml of benzene, pour it into the sealed beaker with a guide tube, and then put the beaker into a magnetic stirrer under ice bath conditions. Measure 5ml of tetrahydrofuran and slowly pour it into the beaker through the guide tube. To prevent tetrahydrofuran from deteriorating, the beaker needs to be placed in an ice bath during this process. After the tetrahydrofuran is completely added, the beaker is sealed, the stirring rate is adjusted to an appropriate value, and the mixture is stirred for 2-3 hours, and then ultrasonically dispersed for 30 minutes to fully dissolve the drug and evenly disperse the particles; (2) Aluminum substrate treatment The aluminum sheet was polished with 400, 800 and 1200 mesh sandpaper in turn, and then chemically degreased to remove the oil stains on the surface of the aluminum sheet, and then pre-etched and weakly etched with dilute hydrochloric acid to remove the oxide film, and then washed with deionized water, and then dried in a vacuum drying oven for standby use; (3) Copper substrate treatment The copper sheet was polished with 400, 800 and 1200 mesh sandpaper in turn, and then chemically degreased to remove the oil stains on the surface of the copper sheet, and then pre-etched and weakly etched with dilute hydrochloric acid to remove the oxide film, and then washed with deionized water, and then dried in a vacuum drying oven for standby use; (4) Constant current electrodeposition With aluminum sheet as anode and copper sheet as cathode, the current density is controlled to be 50 mA / cm2, the bath temperature is 30°C, and the electrodeposition time is 45 min, an Al-SiC composite coating with a dense surface and uniform particle distribution can be obtained, and its main components are Al and SiC. The SEM image, EDS spectrum and XRD spectrum of the sample are shown in Figure 1 , Figure 2 and Figure 3 . Example 2

[0014] (1) Preparation of plating solution Place anhydrous AlCl3, LiAlH4 and SiC particles in a glove box, take out the beaker with the rotor and the medicine spoon from the drying box and place them on the tray, then place the tray in the glove box, seal the glove box and fill it with argon. When the argon fills the entire glove box, weigh the drugs. Use a balance to weigh 4g of anhydrous AlCl3 and 0.28g of anhydrous LiAlH4, put them in a beaker, and then measure a certain amount of SiC particles (40g / L) and put them in the beaker. Seal the weighed beaker, take it out of the glove box and put it in a fume hood. Use a measuring cylinder to measure 20ml of benzene, pour it into the sealed beaker with a guide tube, and then put the beaker into a magnetic stirrer under ice bath conditions. Measure 5ml of tetrahydrofuran and slowly pour it into the beaker through the guide tube. To prevent tetrahydrofuran from deteriorating, the beaker needs to be placed in an ice bath during this process. After the tetrahydrofuran is completely added, the beaker is sealed, the stirring rate is adjusted to an appropriate value, and the mixture is stirred for 2-3 hours, followed by ultrasonic dispersion for 30 minutes to fully dissolve the drug and evenly disperse the particles; (2) Aluminum substrate treatment The aluminum sheet was polished with 400, 800 and 1200 mesh sandpaper in turn, and then chemically degreased to remove the oil stains on the surface of the aluminum sheet, and then pre-etched and weakly etched with dilute hydrochloric acid to remove the oxide film, and then washed with deionized water, and then dried in a vacuum drying oven for standby use; (3) Copper substrate treatment The copper sheet was polished with 400, 800 and 1200 mesh sandpaper in turn, and then chemically degreased to remove the oil stains on the surface of the copper sheet, and then pre-etched and weakly etched with dilute hydrochloric acid to remove the oxide film, and then washed with deionized water, and then dried in a vacuum drying oven for standby use; (4) Constant current electrodeposition Using aluminum sheet as anode and copper sheet as cathode, controlling the current density to 30 mA / cm2, the plating solution temperature to 30°C, and the electrodeposition time to 45 min, an Al-SiC composite coating with a dense surface and uniform particle distribution can be obtained.

Claims

1. Preparation of plating solution: put anhydrous AlCl3, LiAlH4 and SiC particles into a glove box, take out the beaker with the rotor and the medicine spoon from the drying box and put them on the tray, then put the tray into the glove box, seal the glove box and fill it with argon. When the argon fills the entire glove box, weigh the drugs, weigh 4g of anhydrous AlCl3 and 0.28g of anhydrous LiAlH4 on a balance, put them into a beaker, then weigh a certain amount of SiC particles (20g / L~80g / L) and put them into the beaker, and put the weighed drugs into the beaker. The beaker was sealed, taken out from the glove box and placed in a fume hood. 20 ml of benzene was measured with a measuring cylinder, and poured into the sealed beaker through a guide tube. Then the beaker was placed in a magnetic stirrer under ice bath conditions. 5 ml of tetrahydrofuran was measured and slowly poured into the beaker through a guide tube. To prevent the tetrahydrofuran from deteriorating, the beaker was placed in an ice bath during this process. After the tetrahydrofuran was completely added, the beaker was sealed, the stirring rate was adjusted to an appropriate value, stirred for 2-3 hours, and then ultrasonically dispersed for 30 minutes to fully dissolve the drug and evenly disperse the particles.

2. Aluminum substrate treatment: Polish the aluminum sheet with 400, 800 and 1200 mesh sandpaper in turn, then perform chemical degreasing to remove oil stains on the surface of the aluminum sheet, and then use dilute hydrochloric acid for pre-etching and weak etching to remove the oxide film, and then use deionized water to wash, and then put it in a vacuum drying oven to dry for standby use.

3. Copper substrate treatment: Polish the copper sheet with 400, 800 and 1200 mesh sandpaper in turn, then perform chemical degreasing to remove oil stains on the surface of the copper sheet, and then use dilute hydrochloric acid for pre-corrosion and weak corrosion to remove the oxide film, and then use deionized water to wash, put it in a vacuum drying oven to dry after washing, and set aside.

4. Constant current electrodeposition: Use aluminum sheet as anode and copper sheet as cathode, control the current density to 30-50 mA / cm2, control the plating solution temperature to 20-40℃ for electrodeposition, and control the electrodeposition time to 30-75min to obtain an Al-SiC composite coating with a dense surface and uniform particle distribution.

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