A lightweight metal-based composite material and a preparation method thereof

Abstract

A lightweight metal-based composite material and its preparation method include the following components, calculated by mass ratio: inorganic aerogel powder: metal alloy powder = (4-6):1, wherein the metal alloy powder is any of iron-based, titanium-based, aluminum-based, cobalt-based, and nickel-based, and the inorganic aerogel powder is any of oxide aerogel, fluoride aerogel, carbide aerogel, and nitride aerogel. The lightweight metal-based composite material can be prepared using the laser powder bed fusion method using these materials. The present invention introduces inorganic aerogel powder into metal powder. The resulting metal-based composite material combines the advantages of both metal and aerogel, facilitating lightweighting of the metal-based composite material and improving the performance of the composite material.

Description

Technical Field

[0001] The present invention relates to the field of metal materials, and in particular to a lightweight metal-based composite material and a preparation method thereof. Background Art

[0002] Aircraft engines are highly complex and sophisticated thermodynamic machines. As the heart of an aircraft, they not only provide power for flight but also play a vital role in driving the development of aviation. To meet the demands for faster speeds, longer range, and longer lifespans, there is an increasing demand for reducing the weight of aircraft engines and their components. Traditional alloys have limited potential for weight reduction, and some new lightweight alloys have poor high-temperature mechanical properties, failing to meet these requirements. Lightweight metal structural materials, such as titanium, aluminum, and magnesium, offer low density and high specific strength, promising broad applications in aerospace, marine, automotive, and rail transportation. With the advancement and development of science and technology in my country and the continuous improvement of people's living standards, the transportation industry is facing increasingly stringent requirements for energy conservation and emission reduction, and the demand for weight reduction is growing stronger. Lightweight metal structural materials play a crucial role in lightweighting transportation vehicles. However, increasingly complex operating conditions and environments are placing higher demands and challenges on the service performance of lightweight metal materials. Particle-reinforced metal matrix composites (PMCs) are composites made by adding or in-situ generating a particle reinforcement phase to a metal or alloy matrix. These composites can achieve further lightweighting of lightweight metals to a certain extent. Existing research has used various alloy powders, including iron-, aluminum-, titanium-, and nickel-based, as matrix materials, and ceramic particles, such as carbides and nitrides, as reinforcements. However, the weight reduction achieved by these composite materials still falls short of meeting the requirements for use in components such as aircraft engines. Summary of the Invention

[0003] The purpose of the present invention is to solve the above-mentioned problems in the prior art and provide a lightweight metal-based composite material and a preparation method thereof. Inorganic aerogel powder is introduced into metal powder. The prepared metal-based composite material combines the advantages of metal and aerogel, which is conducive to achieving lightweight metal-based composite materials and improving the performance of composite materials.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A lightweight metal-based composite material comprises the following components, measured by mass ratio: inorganic aerogel powder: metal alloy powder = (4-6):1, wherein the metal alloy powder is any one of iron-based, titanium-based, aluminum-based, cobalt-based, and nickel-based, and the inorganic aerogel powder is any one of oxide aerogel, fluoride aerogel, carbide aerogel, and nitride aerogel.

[0006] The iron-based metal is austenitic, duplex, martensitic, precipitation hardening stainless steel, TRIP / TWIP steel, maraging steel, tool steel or ODS steel, preferably 316L stainless steel, 304 austenitic stainless steel, 17-4PH and 15-5PH maraging stainless steel, 18Ni300 maraging steel and H13 tool steel.

[0007] The titanium-based metal is Ti6Al4V (Ti64) alloy; the aluminum-based metal is AlSi12 alloy or AlSi10Mg alloy.

[0008] The cobalt-based metal is a cobalt-chromium alloy; the nickel-based metal is an Inconel 738 alloy, a Hastelloy X alloy, an Inconel 625 alloy, an Inconel 713 alloy or an Inconel 718 alloy.

[0009] The particle size of the metal alloy powder is 50-150 μm, the D50 of the powder is 70-120 μm, and the sphericity of the powder is ≥90%.

[0010] The particle size of the inorganic aerogel powder is 10-50 nm, and the D50 of the powder is 20-30 nm.

[0011] The method for preparing the lightweight metal-based composite material comprises the following steps:

[0012] 1) Mixing metal alloy powder and inorganic aerogel powder in a ball mill according to a proportion;

[0013] 2) After the mixed powder is dried, it is placed in a powder feeding tube of a laser powder bed melting process equipment for laser melting to obtain a lightweight metal matrix composite material.

[0014] In step 1), the ball milling speed is 20-30 r / min, the ball milling time is 4-5 h, and the ball-to-material weight ratio is 3:1.

[0015] The process parameters of laser melting include: laser power of 140 to 180 W, spot diameter of 0.5 to 1 mm, powder feeding rate of 4 to 8 kg / h, and laser scanning rate of 20 to 300 m / min.

[0016] Since the laser energy in the laser powder bed melting method mainly acts on the powder, the mixed powder used in the melting process has a crucial influence on the melting effect. The following indicators are mainly used to characterize the powder: (1) Powder particle size: the size of the powder. Spherical powder is usually characterized by diameter; (2) Sphericity: the degree to which the shape of the powder is similar to that of a sphere; (3) D50: the median value of the powder particle size.

[0017] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0018] 1. The particle size of aerogel powder is at the nanometer level, which can be densely and tightly combined with the metal matrix to improve the performance of the metal matrix composite material. The present invention uses aerogel and metal alloy powder to composite, which can effectively reduce the density of the metal matrix composite material and increase the hardness of the metal matrix composite material, thereby obtaining a lightweight and high-hardness metal matrix composite material.

[0019] 2. Laser Powder Bed Fusion (LPBF) utilizes a high-energy laser beam to irradiate metal powder, completely melting it under the heat of the laser beam, forming a molten pool that solidifies and directly forms the composite. This process is primarily used to prepare particle-reinforced metal matrix composites. Compared to other preparation methods, laser powder bed fusion offers a wider range of substrate materials, a simple preparation process, convenient operation, and easy forming, allowing for the direct production of metal matrix composites of the desired size. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Macroscopic photograph, density and porosity of the composite material prepared in Example 1.

[0021] Figure 2 This is the XRD pattern of the composite material prepared in Example 1.

[0022] Figure 3 This is the hardness of the composite material prepared in Example 1. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0024] Example 1

[0025] In this embodiment, a lightweight metal-based composite material is composed of silicon oxide aerogel powder and 316L stainless steel powder and is produced by laser powder bed fusion.

[0026] The particle size of the silica aerogel powder is 10 to 50 nm, and the D50 of the powder is 24 nm.

[0027] The particle size distribution of 316L stainless steel powder is 50-150 μm, and the D50 of the powder is 87 μm.

[0028] The two powders were uniformly mixed in a ball mill at a mass ratio of silica aerogel: 316L stainless steel = 0:1, 1:1, 2:1, 3:1...9:1. Silica aerogel powder reinforced 316L stainless steel composites were prepared by laser powder bed fusion method and named S0:S1:S2:...S9, respectively.

[0029] Among them, the ball milling speed is 25r / min, the ball milling time is 4h, the ball-to-material weight ratio is 3:1; the laser power is 160W, the spot diameter is 0.8mm, the powder feeding rate is 6kg / h, and the laser scanning rate is 100m / min.

[0030] The macroscopic photos, density and porosity photos of the prepared composite materials are as follows: Figure 1 As shown. Figure 1 (a) to (j) are macroscopic photos of S0:S1:S2:...S9, and (K) is the density and porosity results. Figure 1 It can be seen from the results that the surface density of the composite material becomes worse with the increase of the aerogel content. It can also be seen from the density and porosity results that the density of the SiO2 / 316L stainless steel composite material gradually decreases with the increase of SiO2 content. The SiO2 aerogel (about 0.02~0.25g / cm 3 ) has a density much lower than that of 316L stainless steel (about 7.98g / cm 3 The porosity of SiO2 / 316L stainless steel composites with different ratios of SiO2 aerogel and 316L powder ranged from 18.3% to 37.0%. Overall, the density of the composite material decreased sharply with the increase of SiO2 aerogel (samples S0 to S1), and the decreasing trend slowed with the increase of SiO2 aerogel content (samples S1 to S4). When the particle content increased to a certain level, the decreasing trend further increased (samples S4 to S9).

[0031] The XRD results of the prepared composite materials are as follows: Figure 2 As shown, Figure 2 (a) is the XRD pattern at 20 to 80 degrees. Figure 2 (b) Figure 2 (a) XRD pattern of the local angle. 316L stainless steel is mainly composed of austenite (γ) and secondary martensite (α). With the increase of SiO2 aerogel content, the γ(111) peak intensity gradually weakens, while the α(110) peak intensity gradually increases, indicating that the γ phase transforms to the α phase after the addition of SiO2 aerogel. According to the Bragg equation, the diffraction peak shift is mainly caused by residual stress. Because the thermal expansion coefficient mismatch between SiO2 aerogel and 316L stainless steel significantly increases the residual thermal stress, the peak position shift increases with the addition of SiO2 aerogel.

[0032] The hardness of the prepared composite material is as follows Figure 3 As shown in the figure, the hardness of S0 is 2.72 GPa, and the average hardness of S1 to S9 first increases and then gradually decreases with the increase of SiO2 aerogel. In particular, the hardness drops to about 2.17 GPa in S1, gradually increases to 3.7 GPa in S4, and then gradually decreases to 2.1 GPa in S9.

[0033] A composite material made of silica aerogel powder and 316L stainless steel powder. 316L stainless steel is mainly composed of austenite and a small amount of martensite. When the ratio of silica aerogel to 316L stainless steel is 4:1, austenite transforms into martensite, which increases the hardness of the stainless steel. The comprehensive performance of the composite material is the best at this time. At this time, the hardness is 3.7GPa and the density is 5.67g / cm 3 , the porosity is 21%.

[0034] Example 2

[0035] In this embodiment, a lightweight metal-based composite material is composed of zirconia aerogel powder and aluminum alloy AlSi10Mg powder, and is produced by laser powder bed fusion.

[0036] The particle size of the zirconia aerogel powder is 10 to 50 nm, and the D50 of the powder is 23 nm.

[0037] The particle size distribution of the aluminum alloy powder is 50 to 150 μm, and the D50 of the powder is 89 μm.

[0038] The two powders were uniformly mixed in a ball mill at a mass ratio of zirconium oxide to aluminum alloy powder = 4:1, and a composite material was prepared by laser powder bed fusion.

[0039] Among them, the ball milling speed is 25r / min, the ball milling time is 4h, the ball-to-material weight ratio is 3:1; the laser power is 160W, the spot diameter is 0.8mm, the powder feeding rate is 6kg / h, and the laser scanning rate is 100m / min.

[0040] The composite material in Example 2 was measured to have a hardness of 2.09 GPa and a density of 1.86 g / cm 3 , the porosity is 10%.

[0041] Example 3

[0042] In this embodiment, a lightweight metal-based composite material is composed of alumina aerogel powder and cobalt-chromium alloy powder and is produced by laser powder bed fusion.

[0043] The particle size of the alumina aerogel powder is 10 to 50 nm, and the D50 of the powder is 26 nm.

[0044] The particle size distribution of the cobalt alloy powder is 50 to 150 μm, and the D50 of the powder is 91 μm.

[0045] The two powders were uniformly mixed in a ball mill at a mass ratio of aluminum oxide to cobalt alloy powder = 4:1, and a composite material was prepared by laser powder bed fusion.

[0046] Among them, the ball milling speed is 25r / min, the ball milling time is 4h, the ball-to-material weight ratio is 3:1; the laser power is 160W, the spot diameter is 0.8mm, the powder feeding rate is 6kg / h, and the laser scanning rate is 100m / min.

[0047] The composite material in Example 3 was measured to have a hardness of 4.03 GPa and a density of 6.25 g / cm 3 , the porosity is 15%.

[0048] Aerogel is a novel, lightweight solid material with a micro-nanoporous network structure, with air dispersion media filling the pores. It features extremely low apparent density, high porosity, and a high specific surface area, resulting in excellent barrier properties, extremely low thermal conductivity, and high adsorption, catalytic, and load-bearing capacities. The present invention utilizes aerogel and metal alloy powder to prepare a composite material, effectively reducing the density and increasing the hardness of the metal-based composite.

Claims

1. A method for preparing a lightweight metal-based composite material, characterized in that The following steps are involved: 1) Mix the metal alloy powder and the inorganic aerogel powder in a ball mill according to the ratio; 2) After drying the mixed powder, the mixed powder is placed in a powder feeding tube of a laser powder bed melting process equipment for laser melting to obtain a lightweight metal matrix composite material; The lightweight metal-based composite material comprises the following components, calculated by mass ratio: inorganic aerogel powder: metal alloy powder = (4-6):1, the metal alloy powder is any one of iron-based, titanium-based, aluminum-based, cobalt-based, and nickel-based, and the inorganic aerogel powder is any one of oxide aerogel, fluoride aerogel, carbide aerogel, and nitride aerogel; The metal alloy powder has a particle size of 50 to 150 μm, a D50 of 70 to 120 μm, and a sphericity of 90% or higher. The particle size of the inorganic aerogel powder is 10-50 nm, and the D50 of the powder is 20-30 nm; In step 1), the ball milling speed is 20-30 r / min, the ball milling time is 4-5 h, and the ball-to-material weight ratio is 3:1; The process parameters of laser melting include: laser power of 140~180 W, spot diameter of 0.5~1 mm, powder feeding rate of 4~8 kg / h, and laser scanning rate of 20~300 m / min.

2. The method for preparing a lightweight metal-based composite material according to claim 1, wherein: The iron-based metal is austenitic stainless steel, duplex stainless steel, martensitic stainless steel, precipitation hardening stainless steel, TRIP steel, TWIP steel, maraging steel, tool steel or ODS steel.

3. The method for preparing a lightweight metal-based composite material according to claim 1, wherein: The iron-based metal is 316L stainless steel, 304 austenitic stainless steel, 17-4PH martensitic precipitation hardening stainless steel, 15-5PH martensitic precipitation hardening stainless steel, 18Ni300 maraging steel or H13 tool steel.

4. The method for preparing a lightweight metal-based composite material according to claim 1, wherein: The titanium-based metal is Ti6Al4V (Ti64) alloy; the aluminum-based metal is AlSi12 alloy or AlSi10Mg alloy.

5. The method for preparing a lightweight metal-based composite material according to claim 1, wherein: The cobalt-based metal is a cobalt-chromium alloy; the nickel-based metal is an Inconel 738 alloy, a Hastelloy X alloy, an Inconel 625 alloy, an Inconel 713 alloy or an Inconel 718 alloy.

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