Electrogalvanized stainless steel lattice reinforced aluminum-based composite material and preparation method thereof

Abstract

The invention belongs to the technical field of aluminum-based composite material reinforcement, and discloses an electro-galvanized stainless steel lattice reinforced aluminum-based composite material and a preparation method thereof.The preparation method comprises the steps that firstly, a stainless steel lattice lattice structure is prepared; secondly, after the stainless steel lattice structure is cleaned, activating treatment is conducted; thirdly, the activated stainless steel lattice structure is galvanized; uniformly mixing aluminum-based powder, copper powder, magnesium powder and AlSi10Mg powder to obtain aluminum-based mixed powder, and paving the aluminum-based mixed powder into a graphite mold; the aluminum-based powder is aluminum powder or aluminum alloy powder; fourthly, the galvanized stainless steel lattice lattice structure is placed in the aluminum-based mixed powder laid in the graphite mold, the aluminum-based mixed powder continues to be injected into the graphite mold, and the aluminum-based mixed powder is made to be higher than the galvanized stainless steel lattice lattice structure; and fifthly, after the galvanized stainless steel lattice structure injected with the aluminum-based mixed powder is subjected to vacuum hot pressing sintering, cooling is conducted, and the electro-galvanized stainless steel lattice reinforced aluminum-based composite material is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of aluminum matrix composite material reinforcement, and particularly relates to an electro-galvanized stainless steel lattice reinforced aluminum matrix composite material and a preparation method thereof. Background Art

[0002] Due to its excellent mechanical properties, good corrosion resistance and thermal stability, aluminum matrix composites have a wide range of application prospects in the fields of aerospace, automotive, construction, electronics, etc. Aluminum matrix composites are often enhanced by adding one or more reinforcing materials (such as ceramic particles, short fibers, long fibers, etc.) to improve their strength and stiffness. Usually, ceramic particles are used as the reinforcing phase of aluminum matrix composites [such as ceramic particles of alumina (Al2O3), silicon carbide (SiC), silicon nitride (Si3N4), TiB2, boron carbide, etc.]. Due to the uneven distribution and discontinuity of ceramic particles, it is difficult to control their morphology and size. The discontinuity and aggregation of the reinforcement will lead to stress concentration, reducing the plasticity and toughness of aluminum matrix composites. Although the strength of the material can be improved by introducing ceramic particles, the ductility will be severely reduced, which limits the widespread application of aluminum matrix composites. In addition, the wettability between ceramic particles and the aluminum matrix is poor, and the bonding force is weak, resulting in poor plasticity at the interface and reducing the plasticity and load-bearing capacity of the material. The interface between the ceramic reinforcement phase, fiber reinforcement phase and the aluminum matrix is often mechanical interlocking, with a low interfacial bonding force. Under a large load, peeling and failure will occur at the interface, reducing the overall strength of the aluminum matrix composite. In addition, the thermal expansion systems of ceramic and glass fiber reinforcement phases are quite different from that of the aluminum alloy matrix. When the temperature changes, the thermal expansion coefficients do not match, causing internal stress and affecting the reliability and performance of the material.

[0003] The existing ceramic particle / fiber reinforced aluminum matrix composites have the following bottlenecks:

[0004] (1) The interface between the reinforcement phase and the matrix is mechanical interlocking, with a low bonding strength (usually <50 MPa), and interface peeling is likely to occur.

[0005] (2) The difference in thermal expansion coefficients between the ceramic / fiber and the aluminum matrix (such as ΔCTE≥8×10-6 / K) results in high residual stress (≥200 MPa).

[0006] (3) The random distribution of the reinforcement phase causes significant anisotropy, and the transverse strength loss is ≥30%.

[0007] (4) The reaction between the reinforcement phase and the matrix generates brittle intermetallic compounds, resulting in a reduction in toughness of more than 50%.

[0008] The above problems seriously restrict the engineering applications of aluminum matrix composites in high-load and variable-temperature environments. Summary of the Invention

[0009] The object of the present invention is to provide a preparation method of an electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material, which can improve the interfacial bonding strength between the reinforcement and the matrix, maintain the integrity of the lattice structure, and improve the mechanical properties of the composite material.

[0010] The present invention also provides an electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material.

[0011] The technical solution provided by the present invention is as follows:

[0012] A preparation method of an electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material, comprising the following steps:

[0013] Step 1, prepare a stainless steel lattice structure;

[0014] Step 2, after cleaning the stainless steel lattice structure, perform an activation treatment;

[0015] Step 3, galvanize the activated stainless steel lattice structure; mix aluminum matrix powder, copper powder, magnesium powder and AlSi10Mg powder to obtain an aluminum matrix mixed powder, and spread it into a graphite mold with boron nitride sprayed in the inner cavity;

[0016] Wherein, the aluminum matrix powder is aluminum powder or aluminum alloy powder;

[0017] Step 4, place the galvanized stainless steel lattice structure in the aluminum matrix mixed powder laid in the graphite mold, and continue to inject the aluminum matrix mixed powder into the graphite mold so that the aluminum matrix mixed powder is higher than the galvanized stainless steel lattice structure;

[0018] Step 5, perform vacuum hot pressing and sintering on the galvanized stainless steel lattice structure injected with the aluminum matrix mixed powder, and then cool it with the furnace to obtain an electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material.

[0019] Preferably, in the step 1, the stainless steel lattice structure adopts a 304 stainless steel lattice structure;

[0020] The preparation method of the stainless steel lattice structure is as follows:

[0021] Dry the 304 stainless steel metal powder, and under the protection of nitrogen, use a metal 3D printer to print to obtain a 304 stainless steel lattice structure.

[0022] Preferably, the stainless steel lattice structure is a face-centered cubic lattice structure.

[0023] Preferably, the edge length of the unit cell of the face-centered cubic lattice structure is 3 mm to 10 mm, the lattice rod diameter is 0.25 mm to 2 mm, and the porosity is 70% to 92%.

[0024] Preferably, in the second step, the method for cleaning the stainless - steel lattice structure is as follows:

[0025] Pickle the stainless - steel lattice structure, with the pickling temperature being 40°C to 60°C and the time being 5 min to 10 min;

[0026] Ultrasonically clean the pickled stainless - steel lattice structure with alcohol.

[0027] Preferably, in the second step, activate the stainless - steel lattice structure with hydrochloric acid;

[0028] Among them, the concentration of hydrochloric acid is 100 g to 150 g / L, and the activation treatment time is 45 s to 60 s.

[0029] Preferably, the thickness of the galvanized layer of the stainless - steel lattice structure is 5 μm to 30 μm.

[0030] Preferably, in the third step, the mass ratio of aluminum - based powder, copper powder, magnesium powder and AlSi10Mg powder is 70 - 90:1 - 5:1 - 2.5:10 - 15.

[0031] Preferably, in the fifth step, the process of vacuum hot - pressing sintering includes:

[0032] The first stage: heat up to 350°C to 450°C at a rate of 5°C / min to 10°C / min and hold for 20 min to 30 min;

[0033] The second stage: heat up to 550°C at a rate of 10°C / min and hold for 10 min to 20 min;

[0034] The third stage: heat up to 580°C at a rate of 5°C / min, apply a load of 10 KN to 40 KN, and hold for 0.5 h to 2 h.

[0035] An electro - galvanized stainless - steel lattice - reinforced aluminum - matrix composite material is prepared by using the preparation method of the electro - galvanized stainless - steel lattice - reinforced aluminum - matrix composite material described above.

[0036] The beneficial effects of the present invention are as follows:

[0037] The electro - galvanized stainless - steel lattice - reinforced aluminum - matrix composite material provided by the present invention has excellent performance, can break through the limitations of traditional ceramic / fiber reinforcement, and meet the requirements of engineering applications under high - load and variable - temperature environments.

[0038] The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite provided by the present invention realizes interfacial metallurgical bonding (strength 120-150 MPa) through topological optimization design of the metal lattice reinforcement, preparation of a stainless steel lattice reinforcement with a porosity of 70% to 92% by laser powder bed fusion, and coordination of Zn plating layer interface transition regulation and vacuum hot pressing sintering process parameters, breaks through the accumulation of thermal stress and interfacial brittle failure, realizes the continuous spatial distribution of the reinforcement, and overcomes the technical bottleneck of inhibiting the generation of brittle phases, thus achieving the integrated manufacturing of high-strength and high-toughness aluminum matrix composites. Brief Description of the Drawings

[0039] Figure 1 It is the SEM image at the interface between the stainless steel lattice point structure and the aluminum matrix in the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite prepared in Example 1 of the present invention.

[0040] Figure 2 It is the enlarged SEM macro-morphology image of the stainless steel lattice point structure prepared in Example 2 of the present invention.

[0041] Figure 3 It is the cross-sectional view of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite prepared in Example 2 of the present invention.

[0042] Figure 4 It is the SEM image at the interface between the stainless steel lattice point structure and the aluminum matrix in the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite prepared in Example 2 of the present invention.

[0043] Figure 5 It is the cross-sectional view of the reinforced aluminum matrix composite prepared in Comparative Example 2 of the present invention. Detailed Description of the Invention

[0044] The following further elaborates on the present invention in detail in conjunction with specific examples and drawings, so that those skilled in the art can implement it according to the description in the specification.

[0045] The present invention provides an electro-galvanized stainless steel lattice-reinforced aluminum matrix composite and a preparation method thereof. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite is as follows.

[0046] I. Dry the 304 stainless steel powder.

[0047] The 304 stainless steel powder is spherical or near-spherical particles, the diameter of the powder is distributed in the range of 15 μm to 53 μm, and the tapped density of the powder is 3 cm 3 ~4.7 g / cm 3, the component mass percentages of the 304 stainless steel powder are as follows: 16.51% of Cr, 11.21% of Ni, 2.74% of Mo, 1.06% of Mn, 0.25% of Si, 0.01% of C, 0.003% of S, 0.1% of P, and the balance is iron.

[0048] Other types of stainless steel powder can also be used to replace the 304 stainless steel powder.

[0049] II. Preparation of stainless steel lattice structure

[0050] The stainless steel lattice structure reinforcement has the advantages of low cost, high specific stiffness, strong designability, continuous topological distribution, and strong energy absorption capacity. By regulating the geometric parameters of the lattice structure, such as the unit cell type, relative density, and volume porosity, the required mechanical properties can be achieved. Traditional processing techniques such as machining, casting, and welding are suitable for manufacturing regular lattice structures, but when faced with complex or customized designs, there are problems such as high manufacturing difficulty, material waste, and low efficiency.

[0051] As a preference, the present invention uses 3D printing technology to prepare the stainless steel lattice structure, which can precisely control the micro and macro characteristics of the structure, quickly manufacture complex-shaped, high-performance lattice structure reinforcements, and improve the mechanical properties and energy absorption capacity of the composite material. The specific preparation method is as follows.

[0052] The dried 304 stainless steel powder is printed with a lattice structure using an LPBF metal 3D printer under the protection of a nitrogen atmosphere as the protective gas. When printing, the laser power used is 380W, the laser spot size is 70μm, the scanning pitch is 70μm, the layer thickness is 20μm, and the scanning speed is 2000mm / s. The lattice part is formed by using a "strip" scanning strategy, and each scanning layer is deflected by 45° relative to the previous layer, so as to increase the interlayer bonding force, make the stress distribution uniform, and reduce anisotropy and thermal stress.

[0053] Before the start of the laser powder bed fusion forming process, the oxygen content in the forming chamber is accurately controlled at ≤0.1% with the help of a dynamic gas displacement system, and at the same time, a stripe variable angle scanning strategy is used to prepare a stainless steel lattice reinforcement with a face-centered cubic (FCC) composite topological configuration with a thin-walled barrel. The edge length of the unit cell of the FCC lattice is 3mm - 10mm, the lattice rod diameter is 0.25mm - 2mm, and the porosity is controlled at 70% - 92%, forming a three-dimensional through-network, increasing the powder fluidity, and realizing the synergistic effect of powder fluidity optimization and sintering densification. The design of the edge length of the unit cell being 3mm - 10mm balances the requirement of the stiffness of the structure; the lattice rod diameter is between 0.25mm - 2mm, which can not only ensure the powder fluidity but also guarantee the realization of the forming quality, mechanical properties, and lightweight target.

[0054] III. Cleaning the stainless steel lattice point structure

[0055] First, pickle the printed lattice point structure reinforcement to remove the residual powder, scale, and unfused particles on the surface. The composition of the pickling solution is: 5-15% nitric acid, 10-20% hydrofluoric acid, and the balance is water. The pickling temperature is 40°C - 60°C, and the pickling time is 5 min - 10 min.

[0056] After pickling, ultrasonically clean the printed lattice point structure with alcohol to remove the residual acid solution and the products after pickling, and improve the surface cleanliness.

[0057] IV. Activate the pickled lattice point structure reinforcement to enhance the wettability between the aluminum-based mixed powder and the lattice point structure, promote element diffusion, and improve the interfacial bonding strength.

[0058] The activation liquid used for activation treatment is hydrochloric acid, with a concentration of 100 g / L - 150 g / L, and the activation treatment time is 45 s - 60 s. After activation treatment, then ultrasonically clean with alcohol to remove the residual acid solution and surface impurities on the surface.

[0059] V. Electroplate the stainless steel lattice point structure

[0060] Prepare the electroplating solution. The solvent of the electroplating solution is water, and the content of each component in the electroplating solution is: 30 g / L - 65 g / L zinc chloride, 150 g / L - 260 g / L potassium chloride, 28 g / L - 55 g / L boric acid, 5 g / L - 10 g / L sodium silicate, 2 g / L - 5 g / L aluminum sulfate, and 0.0334 g / L - 0.0446 g / L brightening agent. The pH value of the electroplating solution is 5.6, and the temperature is 45°C.

[0061] Place the prepared electroplating solution in an electrolytic cell, connect the positive electrode to a pure zinc plate, and the negative electrode to the stainless steel lattice point structure reinforcement. Connect the power supply and perform electroplating treatment under ultrasonic conditions. The cathode current density is 2 A / dm 2 , the electroplating time is 10 s - 30 s, and the thickness of the zinc plating layer is 5 μm - 30 μm.

[0062] Performing Zn layer plating treatment on the 304 stainless steel lattice point structure can promote the Al-Zn diffusion reaction, form a metallurgical bond, solve the problem of non-wetting between the reinforcement and aluminum, and improve the interfacial bonding strength between the reinforcement and the matrix.

[0063] VI. Prepare the aluminum-based mixed powder

[0064] Load the atomized spherical aluminum-based powder, pure copper powder, pure magnesium powder, and AlSi10Mg powder into a planetary mixer. After mixing evenly, an aluminum-based mixed powder is obtained. Among them, the mass ratio of the aluminum-based powder, pure copper powder, pure magnesium powder, and AlSi10Mg powder is (70-90):(1-5):(1-2.5):(10-15), and the particle size range is 15μm-53μm.

[0065] Among them, the aluminum-based powder is made of pure aluminum powder or aluminum alloy powder. The aluminum alloy powder is any one of the 1XXX series, 2XXX series, 3XXX series, 4XXX series, 5XXX series, 6XXX series, 7XXX series aluminum alloy spherical powders.

[0066] VII. Inject the aluminum-based mixed powder into the galvanized stainless steel lattice structure

[0067] Lay the aluminum-based mixed powder into a graphite mold with boron nitride sprayed on the inner cavity. The powder laying height is 5mm-10mm. Place the face-centered cubic (FCC) lattice structure reinforcement after electroplating Zn at the center of the powder laying. Under atmospheric pressure conditions, continue to inject the aluminum-based mixed powder into the graphite mold by gravity until the injected aluminum-based mixed powder is 10mm-15mm higher than the reinforcement. After assembly, wait for sintering.

[0068] The face-centered cubic (FCC) lattice structure has high specific stiffness and specific strength, can reduce the structural weight, and also has excellent compressive properties. Using this structure as a reinforcement for preparing aluminum-based composites can effectively improve the compressive capacity of the materials. In addition, the FCC lattice structure performs excellently in energy absorption and dispersion, and can efficiently absorb and dissipate energy.

[0069] VIII. Vacuum hot pressing sintering

[0070] (1) Infiltration casting is a common reinforcement method for aluminum-based composites. However, it has been found through research that using the preparation method of infiltration casting, the 304 stainless steel lattice structure will react with aluminum and aluminum alloys at high temperatures, reducing the mechanical properties of the lattice structure, and the prepared 304 lattice / aluminum composite lacks good interfacial bonding. The present invention uses the method of vacuum hot pressing sintering to reinforce aluminum-based composites. By using the vacuum hot pressing sintering method and controlling the sintering temperature and time, it is possible to avoid the 304 stainless steel lattice structure from contacting aluminum alloy for a long time at high temperatures, prevent the lattice structure from dissolving and the size from becoming smaller, and at the same time reduce the precipitation of Al-Fe intermetallic compounds at the interface and in the matrix. The specific method is as follows.

[0071] Vacuum degree is pumped to 6×10 -4Pa, and then argon is filled for protection. A three-stage heating process is adopted: in the first stage, the temperature is raised from room temperature to 350 - 450 °C, held for 20 - 30 min, and the heating rate is 5 - 10 °C / min; in the second stage, the temperature is raised to 550 °C, held for 10 - 20 min, and the heating rate is 10 °C / min; in the third stage, the temperature is raised to the set value of 580 °C, and the heating rate is 5 °C / min. A load of 10 - 40 KN is applied, the holding time is 0.5 - 2 h, the pressure is unloaded after pressing is completed, and it is cooled in the furnace, then the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material is obtained.

[0072] In this invention, 304 stainless steel is selected as the reinforcement material because it has excellent mechanical properties, heat resistance and good corrosion resistance, and the linear expansion coefficient difference from aluminum alloy is small (304 stainless steel CTE ≈ 17×10-6 / K, aluminum alloy CTE ≈ 23×10-6 / K), which can effectively reduce the residual stress. The Zn coating treatment is carried out on the lattice point structure of 304 stainless steel to promote the Al-Zn diffusion reaction and form a metallurgical bond, which can improve the interfacial bonding strength between the reinforcement and the matrix. The 3D printing technology is used to manufacture the 304 stainless steel lattice point structure, which has the characteristics of strong designability and good processability, and can realize the preparation of complex topological structures. The reinforcement of the aluminum matrix composite material adopted in this invention is a face-centered cubic lattice point structure, which has a high compressive specific stiffness, good compression performance and excellent collapse resistance. The vacuum hot pressing sintering process is adopted, and the sintering temperature and time are effectively controlled to avoid the long-term contact between the 304 stainless steel lattice point structure and aluminum alloy at high temperature, prevent the dissolution and size reduction of the lattice point structure, and at the same time reduce the precipitation of Al-Fe intermetallic compounds in the interface and matrix. In addition, the vacuum hot pressing sintering process can effectively reduce defects such as voids and pores, and further improve the mechanical properties of the aluminum matrix composite material.

[0073] Example 1

[0074] Prepare a face-centered cubic (FCC) 304 stainless steel lattice point structure-reinforced pure aluminum matrix composite material. The face-centered cubic (FCC) stainless steel lattice point structure reinforcement is prepared by 3D printing technology. The unit cell side length is 5 mm, the lattice rod diameter is 0.25 mm, and the porosity is 90.34%. The pickling solution is prepared according to 10% nitric acid, 15% hydrofluoric acid, and the balance is water. The pickling temperature is 55 °C and the pickling time is 10 min. Then, the pickled lattice point structure reinforcement is subjected to an activation treatment. The activation liquid is hydrochloric acid with a concentration of 125 g / L, and the activation treatment time is 50 s. Subsequently, the lattice point structure is subjected to an electro-galvanized coating treatment. The electro-galvanized plating solution formula is: zinc chloride 60 g / L, potassium chloride 200 g / L, boric acid 30 g / L, sodium silicate 5 g / L, aluminum sulfate 2 g / L, brightener 0.0334, pH value 5.6, temperature 45 °C. The cathode current density is 2 A / dm2 , the electroplating time is 20 s, and the thickness of the galvanized layer is 25 μm. Aluminum powder, pure copper powder, pure magnesium powder and AlSi10Mg powder (mass ratio 86:2.5:1.5:10) are loaded into a planetary mixer and mixed evenly to obtain aluminum-based mixed powder with a particle size range of 15 μm to 53 μm. The aluminum-based mixed powder is injected into the center of a graphite mold with boron nitride sprayed on the inner cavity, and the powder laying height is 5 mm. Then, the face-centered cubic (FCC) lattice structure reinforcement of the electroplated coating is placed at the center of the laid powder. Under atmospheric pressure conditions, the aluminum-based mixed powder is continuously injected into the graphite mold by gravity until the injected aluminum-based mixed powder is 10 mm higher than the reinforcement, and after assembly, it is ready for sintering. The vacuum degree is pumped down to 6×10 -4 Pa, and then argon gas is filled for protection. A three-stage heating process is adopted: in the first stage, the temperature is raised from room temperature to 350 °C, held for 20 min, and the heating rate is 5 °C / min; in the second stage, the temperature is raised to 550 °C, held for 20 min, and the heating rate is 10 °C / min; in the third stage, the temperature is raised to 580 °C, and the heating rate is 5 °C / min. A load of 20 KN is applied, and the holding time is 2 h. After the pressing is completed, the pressure is unloaded and cooled with the furnace to obtain the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material. As Figure 1 shown, the stainless steel reinforcement does not dissolve, and the galvanized coating on the surface of the lattice structure effectively hinders the formation of aluminum-iron intermetallic compounds, ensuring good interfacial bonding between the reinforcement and the aluminum matrix.

[0075] Compressive experiment tests are carried out on pure aluminum, the face-centered cubic (FCC) lattice structure of 304 stainless steel, and the 304 stainless steel lattice structure-reinforced aluminum matrix composite material:

[0076] The room temperature compression experiment is carried out according to GB / T7314-2017 at room temperature with a compression rate of 0.05 mm / min. The compression strength of the 304 stainless steel lattice structure-reinforced aluminum matrix composite material is 397 Mpa.

[0077] Example 2

[0078] Prepare a face-centered cubic (FCC) 304 stainless steel lattice structure-reinforced pure aluminum matrix composite material. A face-centered cubic (FCC) stainless steel lattice structure reinforcement is prepared by 3D printing technology, as Figure 2As shown, the side length of the unit cell is 3.3 mm, the lattice rod diameter is 0.5 mm, and the porosity is 87.18%. Prepare a pickling solution with 8% nitric acid, 10% hydrofluoric acid, and the balance being water. The pickling temperature is 45 °C and the pickling time is 8 min. Then, perform an activation treatment on the lattice point structure reinforcement after pickling. The activation liquid is hydrochloric acid with a concentration of 100 g / L, and the activation treatment time is 45 s. Subsequently, perform an electrogalvanized coating treatment on the lattice point structure. The electrogalvanized plating solution formula is: zinc chloride 45 g / L, potassium chloride 160 g / L, boric acid 30 g / L, sodium silicate 5 g / L, aluminum sulfate 2.5 g / L, brightener 0.0339, pH value 5.6, and temperature 45 °C. The cathode current density is 2 A / dm 2 , the electroplating time is 15 s, and the thickness of the galvanized layer is 18 μm. Load 7075 aluminum alloy powder, pure copper powder, pure magnesium powder, and AlSi10Mg powder (mass ratio 89:1.5:1.5:10) into a planetary mixer. After mixing evenly, obtain aluminum-based mixed powder with a particle size range of 15 μm to 53 μm. Inject the aluminum-based mixed powder into the center of a graphite mold with boron nitride sprayed on the inner cavity. The powder laying height is 10 mm, and then place the face-centered cubic (FCC) lattice point structure reinforcement with an electroplated coating at the center of the powder laying. Under atmospheric pressure conditions, continue to inject the aluminum-based mixed powder into the graphite mold by gravity until the injected aluminum-based mixed powder is 10 mm higher than the reinforcement, and wait for sintering after assembly. Evacuate to a vacuum of 6×10 -4 Pa, and then fill with argon for protection. Use a three-stage heating process: In the first stage, heat from room temperature to 450 °C, hold for 30 min, and the heating rate is 5 °C / min; in the second stage, heat to 550 °C, hold for 20 min, and the heating rate is 10 °C / min; in the third stage, heat to the set temperature of 580 °C, and the heating rate is 5 °C / min. Apply a load of 40 KN, hold for 1.5 h, unload the pressure after pressing, and cool with the furnace, then obtain the electrogalvanized 304 stainless steel lattice-reinforced aluminum matrix composite material as shown in Figure 3 . The room temperature compression experiment shows that the average compression strength of the composite material is 730 Mpa.

[0079] The microscopic structure analysis results of the composite material are as shown in Figure 4 . As can be seen from Figure 4 , a metallurgical bond is formed between the electrogalvanized 304 stainless steel reinforcement and the aluminum alloy matrix.

[0080] Comparative Example 1

[0081] Use the same 304 stainless steel lattice point structure as in Example 1, but do not perform the electrogalvanized layer treatment on the lattice point structure. The rest of the preparation process is the same as in Example 1, and a 304 stainless steel lattice point structure-reinforced aluminum matrix composite material is prepared.

[0082] In the room-temperature compression experiment, the compression strength of the 304 stainless steel lattice-reinforced aluminum matrix composite without electro-galvanized coating treatment is 214 Mpa.

[0083] By comparing Example 1 and Comparative Example 1, it can be seen that the galvanizing treatment can enhance the compression strength of the 304 stainless steel lattice structure-reinforced aluminum matrix composite.

[0084] Comparative Example 2

[0085] The 304 stainless steel lattice structure with the same electro-galvanized coating as in Example 2 is used, but instead of the vacuum hot pressing sintering method, the infiltration casting method is adopted to prepare the 304 stainless steel lattice structure-reinforced 7075 aluminum matrix composite. Due to the infiltration casting method, the aluminum liquid needs to be heated above its droplet temperature and is in a superheated state, with a temperature of about 750 °C or higher. At high temperatures, there will be Figure 5 the dissolution phenomenon of the 3D-printed 304 stainless steel lattice structure as shown, the lattice rod diameter becomes smaller, and the compression performance deteriorates. At the same time, there will also be incomplete infiltration, resulting in defects such as voids and pores, leading to a reduction in the mechanical properties of the aluminum matrix composite. The room-temperature compression experiment shows that the average compression strength of the composite prepared by the infiltration casting method is 383 Mpa.

[0086] By comparing Example 2 and Comparative Example 2, it can be seen that, compared with the infiltration casting method, the vacuum hot pressing sintering method can significantly enhance the compression strength of the 304 stainless steel lattice structure-reinforced aluminum matrix composite.

[0087] Although the embodiments of the present invention have been disclosed as above, it is not limited to only the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to specific details and the illustrations shown and described herein.

Claims

1. A preparation method of an electroplated zinc stainless steel lattice reinforced aluminum matrix composite material, characterized in that It includes the following steps: Step 1, prepare a stainless steel lattice structure; Step 2, after cleaning the stainless steel lattice structure, perform an activation treatment; Step 3, galvanize the activated stainless steel lattice structure; mix aluminum-based powder, copper powder, magnesium powder, and AlSi10Mg powder to obtain an aluminum-based mixed powder, and spread it into a graphite mold with boron nitride sprayed in the inner cavity; Among them, the aluminum-based powder is aluminum powder or aluminum alloy powder; Step 4, place the galvanized stainless steel lattice structure in the aluminum-based mixed powder laid in the graphite mold, and continue to inject the aluminum-based mixed powder into the graphite mold so that the aluminum-based mixed powder is higher than the galvanized stainless steel lattice structure; Step 5, perform vacuum hot pressing sintering on the galvanized stainless steel lattice structure injected with the aluminum-based mixed powder, and then cool it with the furnace to obtain an electro-galvanized stainless steel lattice reinforced aluminum matrix composite material.

2. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to claim 1, characterized in that, In the said Step 1, the stainless steel lattice structure adopts a 304 stainless steel lattice structure; The preparation method of the stainless steel lattice structure is: Dry the 304 stainless steel metal powder, and under the protection of nitrogen, use a metal 3D printer to print to obtain a 304 stainless steel lattice structure.

3. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to claim 2, characterized in that The stainless steel lattice structure is a face-centered cubic lattice structure.

4. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to claim 3, characterized in that, The edge length of the unit cell of the face-centered cubic lattice structure is 3 mm to 10 mm, the lattice rod diameter is 0.25 mm to 2 mm, and the porosity is 70% to 92%.

5. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to any one of claims 1-4, characterized in that, In the said Step 2, the method for cleaning the stainless steel lattice structure is: Pickle the stainless steel lattice structure, the pickling temperature is 40°C to 60°C, and the time is 5 min to 10 min; Use alcohol ultrasonic cleaning for the pickled stainless steel lattice structure.

6. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to claim 5, characterized in that, In the said Step 2, use hydrochloric acid to perform an activation treatment on the stainless steel lattice structure; Among them, the concentration of hydrochloric acid is 100 g to 150 g / L, and the activation treatment time is 45 s to 60 s.

7. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to any one of claims 6, characterized in that, The thickness of the galvanized layer of the stainless steel lattice structure is 5 μm to 30 μm.

8. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to claim 7, wherein, In the said Step 3, the mass ratio of the aluminum-based powder, copper powder, magnesium powder, and AlSi10Mg powder is 70 to 90:1 to 5:1 to 2.5:10 to 15.

9. The preparation method of the electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material according to claim 8, characterized in that, In the said Step 5, the process of vacuum hot pressing sintering includes: The first stage, heat up to 350°C to 450°C at a speed of 5°C / min to 10°C / min, and keep warm for 20 min to 30 min; The second stage, heat up to 550°C at a speed of 10°C / min, and keep warm for 10 min to 20 min; The third stage, heat up to 580°C at a speed of 5°C / min, apply a load of 10 KN to 40 KN, and keep warm for 0.5 h to 2 h.

10. An electro-galvanized stainless steel lattice-reinforced aluminum matrix composite material, characterized in that, Prepare by using the preparation method of the electro-galvanized stainless steel lattice reinforced aluminum matrix composite material described in any one of claims 1-9.

Images