A wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material and a preparation method thereof

Abstract

This invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material and its preparation method, belonging to the technical field of ultra-low expansion alloy materials. The aluminum-based composite material is formed by mixing and sintering at least two phases of negative thermal expansion particles and aluminum matrix powder. The negative thermal expansion particles are La... 1‑z C z (Fe 1‑x‑y A x B y ) 13 The series comprises A, a transition metal, B, a metal or half-metal element in the p-block, and C, a lanthanide metal, with a concentration of 0 ≤ x < 0.2, 0.05 < y < 0.25, and 0 ≤ z < 1. The volume percentage of the aluminum matrix is ​​55%–75%. Aluminum is combined with metal-based negative thermal expansion particles. Since metal-based negative thermal expansion materials have higher thermal conductivity than ceramic-based materials, combining them with the aluminum matrix achieves high thermal conductivity. Furthermore, this invention employs at least two phases of negative thermal expansion particles, with the expansion ranges of the two negative thermal expansion particles overlapping to achieve a low expansion effect over a wide temperature range.

Description

Technical Field

[0001] This invention belongs to the field of ultra-low expansion alloy materials technology, and specifically relates to a wide-temperature-range multiphase low expansion lightweight aluminum-based composite material and its preparation method. Background Technology

[0002] In recent years, with the rapid development of high-end technology fields such as aerospace and electronic communications, the requirements for material precision, namely thermal stability, have become increasingly stringent. Traditional materials can no longer meet these requirements due to thermal expansion and contraction and mismatched coefficients of thermal expansion. The emergence of zero thermal expansion materials has attracted widespread attention because their dimensions remain almost unchanged when the external ambient temperature changes. This thermal and mechanical stability makes them promising for applications in aerospace, precision instruments, thermal management, and other fields.

[0003] The emergence of negative thermal expansion materials has attracted widespread attention. They can serve as thermal expansion compensators in metals and even achieve zero thermal expansion composites. Zero thermal expansion composites combine the advantages of both negative thermal expansion materials and metal matrices to achieve good overall performance, but they also have some limitations. First, the zero-expansion temperature range is narrow, which does not meet practical needs. Second, they have poor mechanical properties and high density, which is unsuitable for specific application scenarios. Therefore, developing a wide-temperature-range zero-expansion lightweight composite material and applying it to aerospace and precision instruments will overcome many practical problems in some application areas. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material and its preparation method, which combines aluminum with C(Fe) 1-x-y A x B y ) 13 The negative thermal expansion particles are bonded together due to C(Fe) 1-x-y A x B y ) 13 It belongs to the category of metal-based negative thermal expansion materials, which have stronger thermal conductivity than ceramic-based materials. When combined with an aluminum matrix, it achieves high thermal conductivity. At the same time, this invention uses at least two-phase negative thermal expansion particles, and the expansion ranges of the two negative thermal expansion particles overlap to achieve a low expansion effect over a wide temperature range.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] On one hand, the present invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, wherein the aluminum-based composite material is formed by mixing and sintering at least two phases of negative thermal expansion particles and aluminum matrix powder, wherein the negative thermal expansion particles are La 1-z C z (Fe 1-x-yA x B y ) 13 The series consists of A being a transition metal, B being a metal or half-metal element in the P-block, and C being a lanthanide metal, with 0 ≤ x < 0.2, 0.05 < y < 0.25, and 0 ≤ z < 1, and the volume percentage content of the aluminum matrix is ​​55%-75%.

[0007] Furthermore, A includes any one or more metallic elements selected from Cr, Mn, Co, Ni, Cu, and Zn.

[0008] Furthermore, B includes any one or more metallic elements selected from Si, Ga, Al, and Ge.

[0009] Furthermore, the aluminum matrix includes aluminum alloys and pure aluminum, wherein the aluminum alloy is composed of any one or more alloys selected from Al-Si alloys, Al-Cu alloys, Al-Mg alloys, Al-Zn alloys, and Al-Mn alloys.

[0010] On the other hand, the present invention discloses a method for preparing the above-mentioned wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, comprising the following steps: preparing the negative thermal expansion particles; weighing the negative thermal expansion particles and aluminum matrix powder according to the volume ratio; mixing the weighed negative thermal expansion particles with the aluminum matrix and sintering to obtain the final product.

[0011] Furthermore, the preparation of the negative thermal expansion particles includes: taking the corresponding alloy or element according to the preset phase of the negative thermal expansion particles, mixing the alloy or element required for each component of the negative thermal expansion particles, and preparing the required alloy ingots of each component through multiple high-temperature meltings, and annealing them in a vacuum environment; turning the ingot over once after each melting, and melting more than 4 times; the annealing temperature is 700-1300℃, and the annealing time is at least 4 days; and crushing, grinding, and sieving the annealed alloy ingots.

[0012] Furthermore, the grinding process includes: ball milling the pulverized alloy ingot using a ball mill, wherein the ball milling process is as follows: ball milling at a speed of 200-300 r / min for 10-30 min; ball milling at a speed of 100-150 r / min for 40-50 min; the material-to-ball ratio is 0.8-1.0; and sieving the ball-milled powder to obtain negative thermal expansion particles with a size range of 2-100 μm.

[0013] Furthermore, the aluminum matrix powder has a particle size of 5-100 μm and a D10 of 10-15 μm.

[0014] Furthermore, the weighed negative thermal expansion particles are mixed with the aluminum matrix by ball milling. The ball milling process is as follows: rotation speed 100-250 r / min, ball milling for 30-120 min, material-to-ball ratio of 1.0-1.25, including zirconia or alumina balls with a diameter of 5-20 mm, of which 5 mm zirconia or alumina balls account for 30-50% by mass.

[0015] Furthermore, sintering is carried out using spark plasma sintering under vacuum conditions. The sintering temperature is 50–300°C below the melting point of the aluminum matrix, the applied pressure is not less than 20 MPa, the heating rate is 50–200°C / min, and the holding time is 1–100 min.

[0016] Compared with the prior art, the technical solution provided by the present invention brings the following beneficial effects:

[0017] This invention combines two-phase negative thermal expansion particles with an aluminum matrix. The aluminum matrix has a high thermal conductivity, and the negative thermal expansion particles exhibit significantly improved thermal conductivity compared to ceramic-phase negative thermal expansion materials. Furthermore, in this application, C(Fe) 1-x-y A x B y ) 13 The thermal properties are matched with those of aluminum to prevent large internal stresses between the two phases; secondly, this application uses C(Fe) 1-x-y A x B y ) 13 The series contains at least two types of negative thermal expansion particles. Different materials have different negative thermal expansion ranges. The negative thermal expansion ranges of at least two types of negative thermal expansion particles are superimposed to achieve a low expansion effect over a wide temperature range. When the volume percentage content of the aluminum matrix is ​​55%-75%, the linear expansion coefficient is within 2ppm / K in the range of -50-50℃, and a zero expansion effect with a linear expansion coefficient of less than 1ppm / K is achieved in the temperature range of 100℃. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 LaFe provided in Embodiment 1 of the present invention 11.5-x Co x Si 1.5 Series of material linear expansion curves;

[0020] Figure 2 LaFe provided in Embodiment 1 of the present invention 11.5-x Co x Si 1.5 Linear expansion curve of Al composite material;

[0021] Figure 3 LaFe provided in Embodiment 1 of the present invention 11.5-x Co x Si 1.5 SEM image of Al composite material. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The specific embodiments of this invention are not limited to those given herein, and those skilled in the art can make similar improvements without departing from the spirit of this invention. Therefore, this invention is not limited to the disclosed specific embodiments.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used is for describing particular embodiments only and does not limit the scope of the invention.

[0024] This invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, which is formed by mixing and sintering at least two phases of negative thermal expansion particles and aluminum matrix powder, wherein the negative thermal expansion particles are La 1-z C z (Fe 1-x-y A x B y ) 13 The series consists of A being a transition metal, B being a metal or half-metal element in the P-block, and C being a lanthanide metal, with 0 ≤ x < 0.2, 0.05 < y < 0.25, and 0 ≤ z < 1, and the volume percentage content of the aluminum matrix is ​​55%-75%.

[0025] This invention combines two-phase negative thermal expansion particles with an aluminum matrix. The aluminum matrix has a high thermal conductivity, and the negative thermal expansion particles exhibit significantly improved thermal conductivity compared to ceramic-phase negative thermal expansion materials. Furthermore, the La in this application... 1-z C z (Fe 1-x-y A x B y ) 13 The thermal properties are matched with those of aluminum to prevent large internal stresses between the two phases; secondly, this application uses La 1-z C z (Fe 1-x-y Ax B y ) 13 The series contains at least two types of negative thermal expansion particles. Different materials have different negative thermal expansion ranges. The negative thermal expansion ranges of at least two types of negative thermal expansion particles are superimposed to achieve a low expansion effect over a wide temperature range. When the volume percentage content of the aluminum matrix is ​​55%-75%, the linear expansion coefficient is within 2ppm / K in the range of -50-50℃, and a zero expansion effect with a linear expansion coefficient of less than 1ppm / K is achieved in the temperature range of 100℃.

[0026] C is a lanthanide metal, preferably, C is any one or more of Ce, Pr, Nd, and Y.

[0027] Specifically, the aluminum matrix in this invention is an aluminum alloy and pure aluminum, wherein the aluminum alloy is composed of any one or more alloys selected from Al-Si alloy, Al-Cu alloy, Al-Mg alloy, Al-Zn alloy, and Al-Mn alloy. The metallic elements in the above-mentioned aluminum alloys are related to La. 1-z C z (Fe 1-x-y A x B y ) 13 The generation of intermediate phases between elements is controllable.

[0028] In this embodiment of the invention, La(Fe) is used. 1-x-y Co x Si y ) 13 Please provide an explanation.

[0029] To prepare the above-mentioned aluminum-based composite material, this invention provides a preparation method comprising the following steps:

[0030] S1. Prepare the negative thermal expansion particles.

[0031] According to the preset negative thermal expansion particles, appropriate alloys or elements are selected. These alloys or elements are chemically pure or analytically pure. The required alloys or elements for each component of the negative thermal expansion particles are mixed and subjected to multiple high-temperature melting processes to prepare alloy ingots of the required components. The ingots are then annealed in a vacuum environment. After each melting process, the ingots are turned over, and the melting is repeated at least four times. The annealing temperature is 700-1300℃, and the annealing time is at least four days. The annealed alloy ingots are then crushed, ground, and sieved. The grinding process includes: ball milling the crushed alloy ingots using a ball mill. The ball milling process is as follows: ball milling at a speed of 200-300 r / min for 10-30 min, and then at a speed of 100-150 r / min for 40-50 min; the material-to-ball ratio is 0.8-1.0. The ball-milled powder is then sieved to obtain negative thermal expansion particles with a size range of 2-100 μm.

[0032] Due to La(Fe 1-x-y A x B y ) 13 As an intermetallic compound, La(Fe) exhibits negative thermal expansion compared to porous ceramic phase particles. 1-x-y A x B y ) 13 The surface is relatively smooth, but when the composite material is heated, the aluminum matrix expands, while La(Fe)... 1-x-y A x B y ) 13 contraction, La(Fe) 1-x-y A x B y ) 13 Sufficient tensile force needs to be generated between the surface and the aluminum substrate to restrict the expansion of the aluminum substrate and achieve low or even zero expansion. Based on the above considerations, this invention proposes to use a specific ball milling process to improve the tensile force between the surface of the negative thermal expansion particles and the aluminum substrate. First, a higher rotation speed and a shorter time are used to crush large alloy particles into angular particles. Second, a lower rotation speed and a longer time are used to allow collisions between the edges and planes of the particles, which increases the randomness of the collisions and increases the mechanical bonding strength between the surface of the negative thermal expansion particles and the aluminum substrate.

[0033] S2. Weigh the negative thermal expansion particles and aluminum matrix powder according to the volume ratio.

[0034] Weigh the aforementioned negative thermal expansion particles and aluminum matrix powder, wherein the particle size of the aluminum matrix powder is 5-100 μm and the D10 is 10-15 μm. Sieving ensures the particle size of the aluminum matrix powder is within the range of 5-100 μm. By limiting the particle size and D10 range of the aluminum matrix powder, during subsequent mixing, the aluminum matrix powder mechanically coats the surface of the negative thermal expansion particles. In particular, smaller aluminum matrix powder particles interlock with the tiny grooves on the surface of the negative thermal expansion particles, preventing the settling of powders of different sizes during sintering. This avoids the problem of larger particles mainly depositing at the top of the mold, while smaller particles deposit at the bottom, resulting in uneven product performance.

[0035] S3. After weighing the negative thermal expansion particles, mix them with the aluminum matrix and sinter them to obtain the final product.

[0036] The weighed negative thermal expansion particles are mixed with an aluminum matrix using ball milling. The ball milling process is as follows: rotation speed 100-250 r / min, milling time 30-120 min, material-to-ball ratio 1.0-1.25, including zirconia or alumina balls with a diameter of 5-20 mm, of which 5 mm zirconia or alumina balls account for 30-50% by mass. The lower rotation speed and longer time allow sufficient time for the aluminum matrix powder to coat the surface of the negative thermal expansion particles. However, the ball milling time and rotation speed should not be too long or too high, otherwise a large proportion of the negative thermal expansion particles will be crushed, reducing the mechanical coating of the negative thermal expansion particles by the aluminum matrix powder.

[0037] Sintering was performed using spark plasma sintering under vacuum conditions. The sintering temperature was 50–300°C below the melting point of the aluminum matrix, with a pressure of not less than 20 MPa, a heating rate of 50–200°C / min, and a holding time of 1–100 min. Spark plasma sintering allows for effective bonding between multiphase negative thermal expansion particles and the aluminum matrix in a short time and at a relatively low temperature, minimizing the formation of excessive intermediate phases, such as Al. 13 Fe4, along with the above process, can generate an intermediate phase with a thickness of 10-50 nm. This intermediate phase can be used to metallurgically bond negative thermal expansion particles to the aluminum matrix. Furthermore, this intermediate phase can coordinate the interface between the negative thermal expansion particles and the aluminum matrix, avoiding problems such as cracking when the strain between them exceeds the maximum strain at that point.

[0038] To further illustrate the present invention, the following detailed description of a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material provided by the present invention is provided in conjunction with embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0039] Example 1

[0040] This invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, the preparation method of which includes:

[0041] S1. Prepare the negative thermal expansion particles.

[0042] Based on a stoichiometric ratio of 1:11.5-m:m:1.5, where m = 0.4, 0.6, 0.8, 1.0, and 1.2, elemental metals La, Fe, Co, and Si (purity ≥ 99.5%) were weighed out and placed sequentially in an electric arc furnace for high-temperature melting under a high-purity argon atmosphere. After each melting cycle, the alloy ingot was turned over to ensure homogeneity, for a total of four melting cycles. The prepared alloy ingot was then annealed in a vacuum environment at 700℃ for four days. Figure 1 As shown, it can be seen that the alloy type LaFe 11.5-x Co x Si 1.5The negative thermal expansion temperature ranges of the series of materials are different but continuous.

[0043] After annealing, the alloy ingot is crushed with alcohol and ground into powder. The powder is then sieved to achieve a particle size range of 5-100μm. The ball milling process is as follows: ball milling at 200r / min for 10min, and then ball milling at 100r / min for 40min; the material-to-ball ratio is 0.8.

[0044] S2. Weigh the negative thermal expansion particles and aluminum matrix powder according to the volume ratio.

[0045] Weigh out equal amounts of the five alloy powders mentioned above, and weigh out multiphase alloy powder and pure aluminum powder in a volume ratio of 40:60. The aluminum powder has a particle size range of 5 to 100 μm and a D10 of 10 μm.

[0046] S3. After weighing the negative thermal expansion particles, mix them with the aluminum matrix and sinter them to obtain the final product.

[0047] The above-mentioned negative thermal expansion particles were mixed with an aluminum matrix and then ball-milled in alcohol. The ball milling process was as follows: rotation speed 100 r / min, ball milling for 30 min, material-to-ball ratio of 1.0, using zirconia balls, including zirconia balls with diameters of 5 mm and 10 mm, of which the 5 mm zirconia balls accounted for 30% by mass.

[0048] Sintering was carried out using spark plasma sintering under vacuum conditions at a temperature of 550±10℃ and a pressure of 50±0.5MPa. The temperature was increased at a uniform rate for 7 minutes and held for 7 minutes.

[0049] Figure 2 For La(Fe, Co, Si) 13 The linear expansion curve of the Al composite material shows that, between -50℃ and 30℃, the negative coefficient of thermal expansion of the composite material is 0.88 × 10⁻⁶. -6 / ℃, indicating that multiphase LaFe 11.5-x Co x Si 1.5 When the series of particles are combined with pure aluminum, zero expansion over a wide temperature range can be achieved.

[0050] Figure 3 For La(Fe, Co, Si) 13 SEM images of La(Fe, Co, Si) composite materials. 13 The aluminum is evenly distributed and the structure is dense, so the prepared composite material has excellent mechanical properties and high strength and plasticity.

[0051] Example 2

[0052] This invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, the preparation method of which includes:

[0053] S1. Prepare the negative thermal expansion particles.

[0054] Based on a stoichiometric ratio of 1:11.5-m:m:1.5, where m = 0.4, 0.6, 0.8, 1.0, and 1.2, elemental metals La, Fe, Co, and Si (purity ≥ 99.5%) were weighed out and placed sequentially in an electric arc furnace for high-temperature melting under a high-purity argon atmosphere. After each melting cycle, the alloy ingot was turned over to ensure homogeneity, for a total of 5 melting cycles. The prepared alloy ingot was then annealed in a vacuum environment at 1000℃ for 4 days.

[0055] After annealing, the alloy ingot is crushed with alcohol and ground into powder. The powder is then sieved to achieve a particle size range of 5-100μm. The ball milling process is as follows: ball milling at 200r / min for 10min, and then ball milling at 100r / min for 40min; the material-to-ball ratio is 0.8.

[0056] S2. Weigh the negative thermal expansion particles and aluminum matrix powder according to the volume ratio.

[0057] Weigh out equal amounts of the five alloy powders mentioned above, and weigh out multiphase alloy powder and pure aluminum powder at a volume ratio of 40:55. The aluminum powder has a particle size range of 5 to 100 μm and a D10 of 12 μm.

[0058] S3. After weighing the negative thermal expansion particles, mix them with the aluminum matrix and sinter them to obtain the final product.

[0059] The above-mentioned negative thermal expansion particles were mixed with an aluminum matrix and then ball-milled in alcohol. The ball milling process was as follows: rotation speed 100 r / min, ball milling for 40 min, material-to-ball ratio of 1.0, using alumina balls, including alumina balls with diameters of 5 mm and 10 mm, of which the mass proportion of 5 mm alumina balls was 30%.

[0060] Sintering was carried out using spark plasma sintering under vacuum conditions at a temperature of 550±10℃, a pressure of 20±0.5MPa, a heating rate of 50℃ / min, and a holding time of 1min.

[0061] La(Fe, Co, Si) 13 The aluminum is evenly distributed and the structure is dense, so the prepared composite material has excellent mechanical properties and high strength and plasticity.

[0062] Example 3

[0063] This invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, the preparation method of which includes:

[0064] S1. Prepare the negative thermal expansion particles.

[0065] Based on a stoichiometric ratio of 1:11.5-m:m:1.5, where m = 0.4, 0.6, 0.8, 1.0, and 1.2, elemental metals La, Fe, Co, and Si (purity ≥ 99.5%) were weighed out and placed sequentially in an electric arc furnace for high-temperature melting under a high-purity argon atmosphere. After each melting cycle, the alloy ingot was turned over to ensure homogeneity, for a total of 5 melting cycles. The prepared alloy ingot was then annealed in a vacuum environment at 1000℃ for 4 days.

[0066] After annealing, the alloy ingot is crushed with alcohol and ground into powder. The powder is then sieved to achieve a particle size range of 5-100μm. The ball milling process is as follows: ball milling at 250r / min for 20min, and then ball milling at 100r / min for 45min; the material-to-ball ratio is 0.9.

[0067] S2. Weigh the negative thermal expansion particles and aluminum matrix powder according to the volume ratio.

[0068] Weigh out equal amounts of the five alloy powders mentioned above, and weigh out multiphase alloy powder and pure aluminum powder at a volume ratio of 40:70. The aluminum powder has a particle size range of 5 to 100 μm and a D10 of 12.2 μm.

[0069] S3. After weighing the negative thermal expansion particles, mix them with the aluminum matrix and sinter them to obtain the final product.

[0070] The above-mentioned negative thermal expansion particles were mixed with an aluminum matrix and then ball-milled in alcohol. The ball milling process was as follows: rotation speed 150 r / min, ball milling for 60 min, material-to-ball ratio of 1.1, using zirconia balls, including zirconia balls with diameters of 5 mm and 10 mm, of which the 5 mm zirconia balls accounted for 40% by mass.

[0071] Sintering was carried out using spark plasma sintering under vacuum conditions at a temperature of 550±10℃, a pressure of 20±0.5MPa, a heating rate of 50℃ / min, and a holding time of 1min.

[0072] La(Fe, Co, Si) 13 The aluminum is evenly distributed and the structure is dense, so the prepared composite material has excellent mechanical properties and high strength and plasticity.

[0073] Example 4

[0074] This invention provides a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, the preparation method of which includes:

[0075] S1. Prepare the negative thermal expansion particles.

[0076] Based on a stoichiometric ratio of 1:11.5-m:m:1.5, where m = 0.4, 0.6, 0.8, 1.0, and 1.2, elemental metals La, Fe, Co, and Si (purity ≥ 99.5%) were weighed out and placed sequentially in an electric arc furnace for high-temperature melting under a high-purity argon atmosphere. After each melting cycle, the alloy ingot was turned over to ensure homogeneity, for a total of four melting cycles. The prepared alloy ingot was then annealed in a vacuum environment at 1300℃ for four days.

[0077] The annealed alloy ingot was crushed with alcohol and ground into powder. The powder was then sieved to achieve a particle size range of 5-100μm. The ball milling process was as follows: ball milling at 300r / min for 30min and then at 150r / min for 50min; the material-to-ball ratio was 1.0.

[0078] S2. Weigh the negative thermal expansion particles and aluminum matrix powder according to the volume ratio.

[0079] Weigh out equal amounts of the five alloy powders mentioned above, and weigh out multiphase alloy powder and pure aluminum powder at a volume ratio of 40:75. The aluminum powder has a particle size range of 5 to 100 μm and a D10 of 14.8 μm.

[0080] S3. After weighing the negative thermal expansion particles, mix them with the aluminum matrix and sinter them to obtain the final product.

[0081] The above-mentioned negative thermal expansion particles were mixed with an aluminum matrix and then ball-milled in alcohol. The ball milling process was as follows: rotation speed 250 r / min, ball milling for 120 min, material-to-ball ratio of 1.25, using zirconia balls, including zirconia balls with diameters of 5 mm and 10 mm, of which the 5 mm zirconia balls accounted for 50% by mass.

[0082] Sintering was carried out using spark plasma sintering under vacuum conditions at a temperature of 550±10℃, a pressure of 40±0.5MPa, a heating rate of 200℃ / min, and a holding time of 100min.

[0083] La(Fe, Co, Si) 13 The aluminum is evenly distributed and the structure is dense, so the prepared composite material has excellent mechanical properties and high strength and plasticity.

[0084] Comparative Example 1

[0085] Unlike Example 1, in this comparative example, the ball milling process in step S1 is as follows: ball milling at a speed of 200 r / min for 50 min.

[0086] Comparative Example 2

[0087] Unlike Example 1, in this comparative example, the ball milling process in step S1 is as follows: ball milling at a speed of 150 r / min for 50 min.

[0088] Comparative Example 3

[0089] Unlike Example 1, in this comparative example, the D10 of the aluminum matrix powder is 8 μm.

[0090] Comparative Example 4

[0091] Unlike Example 1, in this comparative example, the D10 of the aluminum matrix powder is 17 μm.

[0092] Comparative Example 5

[0093] Unlike Example 1, in this comparative example, the ball milling process in step S3 is as follows: rotation speed 90 r / min, ball milling for 130 min.

[0094] Comparative Example 6

[0095] Unlike Example 1, in this comparative example, the ball milling process in step S3 is as follows: rotation speed 260 r / min, ball milling for 28 min.

[0096] Comparative Example 7

[0097] Unlike Example 1, the holding time for the spark plasma sintering process in this comparative example is 105 min.

[0098] Comparative Example 8

[0099] Unlike Example 1, the holding time for the spark plasma sintering process in this comparative example is 0.5 min.

[0100] The samples prepared in the above embodiments and comparative examples were tested, and the data obtained are shown in Table 1.

[0101] Methods for determining compressive strength and elongation: The compressive strength of the material is measured using a WDW-200D electronic universal testing machine. The sample is clamped in the indenter, and pressure is applied at a specified rate. The measuring system collects the applied pressure value and deformation. Before starting, the area of ​​the compression surface is measured, and the ratio of pressure to area is the pressure. A compressive stress-strain curve is then plotted. The dimensions of the compression sample are determined according to GBT7314-2005 standard; the aspect ratio of cylindrical samples is 2.5 to 3.5.

[0102] Durability test: The sample is repeatedly heated and cooled at a rate of 20℃ / min between -100℃ and 100℃. After 1000 cycles, the grain boundaries of the sample are inspected by SEM to check for cracks. If a crack is found, it is considered to have been found.

[0103] Uniformity: For the prepared sample, samples are taken from the top, bottom, left, right, front, back and center, and the area occupied by the aluminum substrate at different locations is detected. If the deviation of the area occupied by the aluminum substrate at different locations does not exceed 5%, the uniformity is good; if it is greater than 5%, the uniformity is poor.

[0104] Table 1. Test results of samples from each embodiment and comparative example.

[0105]

[0106] Examples 1, 1, and 2 demonstrate that ball milling improves the physical properties of the surface of the negative thermal expansion particles and enhances the bonding strength between the particles and the aluminum matrix. High-speed or low-speed ball milling alone cannot achieve the bonding strength required in this application. Examples 1, 3, and 4 show that the particle size and distribution of different aluminum matrix powders significantly impact the quality of the subsequent product. A suitable particle size allows for matching with the surface of the negative thermal expansion particles after processing, facilitating mechanical bonding and preventing uneven distribution of aluminum matrix powders of different sizes during subsequent preparation, which could lead to inconsistent product properties. Examples 1, 5, and 6 show that rotation speed and time are crucial in the subsequent mixing process. Too low a speed results in insufficient impact force during ball milling, hindering effective mechanical bonding between the aluminum matrix powder and the negative thermal expansion particle surface. Conversely, too high a speed leads to excessive impact force, easily pulverizing the negative thermal expansion particles and creating a new smooth surface, increasing the difficulty of bonding with the aluminum matrix. Through Example 1, Comparative Examples 7 and 8, it can be seen that in Comparative Example 8, less intermediate phase is generated, so the deformation between the negative thermal expansion particles and the aluminum matrix cannot be effectively coordinated. In Comparative Example 7, more intermediate phase is generated, so the negative thermal expansion effect of the negative thermal expansion phase is weakened.

[0107] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, characterized in that, The aluminum-based composite material is formed by mixing and sintering at least two phases of negative thermal expansion particles and aluminum matrix powder, wherein the negative thermal expansion particles are La 1-z C z (Fe 1-x-y A x B y ) 13 The series includes A, B, and C, where A is a transition metal, B is a metal or half-metal element in the P-block, and C is a lanthanide metal. The aluminum content is 0 ≤ x < 0.2, 0.05 < y < 0.25, and 0 ≤ z < 1. The volume percentage content of the aluminum matrix is ​​55%-75%. The aluminum matrix powder has a particle size of 5μm-100μm and a D10 of 10μm-15μm; The weighed negative thermal expansion particles were mixed with aluminum matrix powder by ball milling. The ball milling process was as follows: rotation speed 100 r / min - 250 r / min, ball milling for 30 min - 120 min, material-to-ball ratio 1.0-1.25, including zirconia or alumina balls with a diameter of 5 mm to 20 mm, of which 5 mm zirconia or alumina balls accounted for 30%-50% by mass. Sintering was carried out using spark plasma sintering under vacuum conditions. The sintering temperature was 50℃~300℃ below the melting point of the aluminum matrix, the applied pressure was not less than 20MPa, the heating rate was 50℃ / min - 200℃ / min, and the holding time was 1 min - 100 min.

2. The wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material according to claim 1, characterized in that, The A includes any one or more metallic elements selected from Cr, Mn, Co, Ni, Cu, and Zn.

3. The wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material according to claim 1, characterized in that, B includes any one or more metallic elements selected from Si, Ga, Al, and Ge.

4. The wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material according to claim 1, characterized in that, The aluminum matrix includes aluminum alloys and pure aluminum, wherein the aluminum alloy is composed of any one or more alloys selected from Al-Si alloy, Al-Cu alloy, Al-Mg alloy, Al-Zn alloy, and Al-Mn alloy.

5. A method for preparing a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material, characterized in that, The preparation method is used to prepare a wide-temperature-range multiphase low-expansion lightweight aluminum-based composite material according to any one of claims 1-4, comprising the following steps: Prepare the negative thermal expansion particles; Weigh the negative thermal expansion particles and aluminum matrix powder according to the volume ratio; The weighed negative thermal expansion particles are mixed with the aluminum matrix and then sintered to obtain the final product.

6. The preparation method according to claim 5, characterized in that, The preparation of the negative thermal expansion particles includes: According to the preset negative thermal expansion particles, take the corresponding alloy or element, mix the alloy or element required for each component of negative thermal expansion particles, and prepare the required alloy ingots of each component after multiple high-temperature meltings and anneal in a vacuum environment; after each melting, turn the ingot over once, and melt more than 4 times; the annealing temperature is 700℃-1300℃, and the annealing time is at least 4 days. The annealed alloy ingots are crushed, ground, and sieved.

7. The preparation method according to claim 6, characterized in that, The grinding process includes: grinding the pulverized alloy ingots using a ball mill, wherein the ball milling process is as follows: ball milling at a speed of 200r / min-300r / min for 10 min-30 min; and ball milling at a speed of 100r / min-150r / min for 40 min-50 min. The material-to-ball ratio is 0.8-1.0; The ball-milled powder was sieved to obtain negative thermal expansion particles with a size range of 2μm-100μm.

Images