Aluminum-tungsten-copper multi-component alloy and preparation method thereof

Abstract

The invention discloses an aluminum-tungsten-copper multi-component alloy and a preparation method thereof, and belongs to the technical field of metal materials and sintering manufacturing thereof. The aluminum-tungsten-copper multi-component alloy comprises the following components in parts by mass: 13.5 to 17.6 parts of aluminum, 70.0 to 77.0 parts of tungsten, 9.0 to 12.0 parts of copper, 0.3 to 2.5 parts of nickel, 0.1 to 2.0 parts of molybdenum, 0.05 to 1.2 parts of titanium, 0.02 to 0.90 part of zirconium, 0.02 to 0.65 part of boron and 0.1 to 0.3 part of impurity elements. Wherein the impurity elements comprise oxygen, nitrogen, carbon and hydrogen. According to the aluminum-tungsten-copper multi-component alloy and the preparation method thereof provided by the invention, by optimizing the component design, the prepared aluminum-tungsten-copper multi-component alloy has the advantages of high density, uniform structure and excellent specific strength; a novel material solution is provided for the fields such as aerospace and electronic devices which have strict requirements on the specific strength and the comprehensive performance of the material.

Description

Technical Field

[0001] The present invention relates to the technical field of metal materials and sintering manufacturing thereof, and in particular to an aluminum-tungsten-copper multi-element alloy and a preparation method thereof. Background Art

[0002] Aluminum and its alloys are widely used in aerospace, automotive, and other fields due to their lightweight and excellent mechanical properties, and are particularly suitable for applications requiring high relative strength. However, pure aluminum and simple alloys have limitations in terms of high-temperature strength and wear resistance. Tungsten, as a high-melting-point metal, offers excellent mechanical strength and high-temperature resistance, but its high density limits its applications. Copper, known for its excellent electrical and thermal conductivity, can enhance the overall performance of alloys.

[0003] In recent years, aluminum-tungsten-copper (Al-W-Cu) alloys, as novel composite materials, have demonstrated unique advantages in high-strength-to-weight ratio applications by combining the lightweight of aluminum, the high strength of tungsten, and the electrical and thermal conductivity of copper. However, when subjected to high tungsten content, the smelting method, due to tungsten's high melting point and density differences, leads to severe elemental segregation and uneven microstructure. The mechanical alloying process is prone to impurity contamination and significant grain refinement, affecting alloy properties. Traditional press-sintering processes, however, struggle to achieve ideal density and interfacial bonding due to insufficient sintering activity. These technical challenges severely restrict the preparation of high-performance Al-W-Cu alloys. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an aluminum-tungsten-copper multi-element alloy and a preparation method thereof. By optimizing the composition design, the prepared aluminum-tungsten-copper multi-element alloy has the advantages of high density, uniform structure and excellent specific strength, providing a new material solution for fields such as aerospace and electronic devices that have strict requirements on material specific strength and comprehensive performance.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] In one aspect, the present invention provides an aluminum-tungsten-copper multi-element alloy comprising the following components in parts by mass: 13.5 to 17.6 parts of aluminum, 70.0 to 77.0 parts of tungsten, 9.0 to 12.0 parts of copper, 0.3 to 2.5 parts of nickel, 0.1 to 2.0 parts of molybdenum, 0.05 to 1.2 parts of titanium, 0.02 to 0.90 parts of zirconium, 0.02 to 0.65 parts of boron, and 0.1 to 0.3 parts of impurity elements;

[0007] The impurity elements include oxygen, nitrogen, carbon and hydrogen.

[0008] In another aspect, the present invention provides a method for preparing the aluminum-tungsten-copper multi-element alloy, comprising:

[0009] Weigh raw material powders of aluminum, tungsten, copper, nickel, molybdenum, titanium, zirconium and boron in parts by mass, and perform mechanical alloying treatment on the raw material powders;

[0010] Screening the mechanically alloyed powder to obtain powder with a particle size within a preset particle size range;

[0011] The powder with a particle size within a preset range is sintered to obtain an aluminum-tungsten-copper multi-element alloy.

[0012] Furthermore, the particle sizes of the aluminum, tungsten and copper powders in the raw material powders are all less than 100 μm.

[0013] Furthermore, the preset particle size range is 10~90μm.

[0014] Furthermore, the mechanical alloying treatment is a wet ball milling treatment, comprising:

[0015] The weighed raw material powder, zirconium oxide balls, medium and dispersant are placed in a ball mill at a mass ratio of 1:5:(2-3):0.01 and ball milled at a speed of 200-300 rpm for 0.5-2 hours to obtain a ball-milled powder, wherein the medium is anhydrous ethanol and the dispersant is polyethylene glycol PEG;

[0016] The ball-milled powder was placed in a vacuum drying oven and dried at 60-80°C for 4 hours to obtain the final mechanically alloyed powder.

[0017] Furthermore, the sintering process includes:

[0018] Filling powder with a particle size within a preset range into a sintering mold and assembling the sintering mold;

[0019] Place the assembled sintered abrasive tool in a vacuum environment and pre-press it at a pressure of 20-25 MPa;

[0020] The temperature was raised to 600-670°C at 100°C / min, the pressure was increased to 40-50 MPa, maintained for 6-12 minutes, and then cooled to room temperature to complete sintering.

[0021] Furthermore, carbon paper is laid on the bottom of the sintering mold, powder with a particle size within a preset range is filled into the sintering mold to form a powder layer, a layer of carbon paper is placed above the powder layer, and finally the sintering mold is assembled.

[0022] Furthermore, after the aluminum-tungsten-copper multi-element alloy is obtained through sintering, the aluminum-tungsten-copper multi-element alloy is subjected to mechanical processing.

[0023] Furthermore, the mechanical processing includes:

[0024] Removal of carbon paper from the surface of aluminum-tungsten-copper alloy;

[0025] Polishing the surface of the aluminum-tungsten-copper multi-element alloy;

[0026] Processing of aluminum-tungsten-copper multi-element alloys according to preset drawings.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention provides an aluminum-tungsten-copper multi-element alloy and a preparation method thereof. The aluminum-tungsten-copper multi-element alloy comprises the following components by weight: 13.5 to 17.6 parts aluminum, 70.0 to 77.0 parts tungsten, 9.0 to 12.0 parts copper, 0.3 to 2.5 parts nickel, 0.1 to 2.0 parts molybdenum, 0.05 to 1.2 parts titanium, 0.02 to 0.90 parts zirconium, 0.02 to 0.65 parts boron, and 0.1 to 0.3 parts impurity elements. The impurity elements include oxygen, nitrogen, carbon, and hydrogen. Through optimized composition design, the aluminum-tungsten-copper multi-element alloy prepared has the advantages of high density, uniform structure, and excellent specific strength, providing a new material solution for fields such as aerospace and electronic devices, which have strict requirements on material specific strength and comprehensive performance. DETAILED DESCRIPTION

[0029] The present invention will be further described below. The following examples are only used to more clearly illustrate the technical solution of the present invention and are not intended to limit the scope of protection of the present invention.

[0030] Example 1

[0031] This embodiment provides an aluminum-tungsten-copper multi-element alloy and a preparation method thereof, the preparation method comprising:

[0032] S1. Raw material weighing

[0033] Weigh 15.0 g of aluminum powder (Al), 75.0 g of tungsten powder (W), 10.0 g of copper powder (Cu), 1.0 g of nickel powder (Ni), 1.0 g of molybdenum powder (Mo), 0.5 g of titanium powder (Ti), 0.3 g of zirconium powder (Zr), and 0.2 g of boron powder (B). The purity of all raw materials used should be no less than 99.5%. The particle size of the aluminum, tungsten, and copper powders should be less than 100 μm. The particle size of the other additive element powders (nickel powder, molybdenum powder, titanium powder, zirconium powder, and boron powder) should be less than 75 μm.

[0034] S2.1 Mixed powder

[0035] Weighed powder and zirconia balls were placed in a stainless steel ball mill at a ball-to-material ratio of 5:1. Wet milling was performed using anhydrous ethanol as the medium. The solvent addition amount was twice the powder mass. Polyethylene glycol (PEG) was used as a dispersant (1 wt% of the total powder mass). The milling speed was set at 300 rpm for 1 hour. Pause stirring every 0.5 hours and check the powder mix for uniformity to prevent agglomeration or excessive fragmentation. After ball milling, the wet powder was placed in a vacuum drying oven and dried at 70°C for 4 hours. After completion, the powder particle distribution and surface morphology were inspected to ensure uniform mixing.

[0036] S2.2. Detection of particle size

[0037] The powder particle size is tested by a particle size analyzer to ensure that it reaches the required size, i.e. 10~90μm.

[0038] S3, screening

[0039] A sieve with a mesh size of 200-500 was selected to sieve the powder after mechanical alloying to collect qualified powder with a particle size of 10-90 μm.

[0040] S4.1. Equipment initialization

[0041] Ensure that the spark plasma sintering system is in normal working condition and perform necessary calibration and maintenance

[0042] S4.2. Powder filling

[0043] Choose a graphite mold and ensure it is clean inside and out, free of residual impurities. The contact surfaces between the lower punch, the graphite mold cavity, and the upper punch must be smooth. Use high-quality graphite paper (0.2 mm thick). Cut a piece of carbon paper to the appropriate size based on the inner dimensions of the mold cavity, ensuring that the paper completely covers the mold walls and the contact surfaces between the upper and lower punches to prevent direct contact between the powder and the mold. First, place a layer of cut carbon paper at the bottom of the mold. Slowly pour the mixed Al-W-Cu powder into the mold, avoiding vibrating the powder and causing it to separate. Then, use a vibrating tool or tap the mold gently to ensure a dense distribution of the powder while avoiding excessive accumulation that could cause uneven distribution. Place a layer of cut carbon paper on top of the powder, ensuring even coverage and compaction. Finally, place the upper punch on top of the carbon paper, ensuring close contact between the punch and the paper. Assemble the mold (including the upper and lower punches) and confirm that all components are securely connected.

[0044] S4.3 Sintering process

[0045] After assembly, the mold was placed in the vacuum chamber of the SPS equipment and the vacuum pump was turned on to achieve a high vacuum (residual pressure was controlled below 10 Pa) to prevent oxidation of the aluminum powder at high temperatures. Pre-pressing was then performed at a pressure of 27.5 MPa to ensure close contact between the powder particles and reduce porosity. The heating phase began with a heating rate of 100°C / min and a target temperature of 650°C. During the heating process, the pressure was gradually increased to 45 MPa. Once the temperature reached 650°C, it was held at that temperature for 8 minutes to complete sintering. After sintering, the mold was allowed to cool naturally to room temperature within the equipment.

[0046] S5.1. Remove the contaminated carbon paper coating:

[0047] Use appropriate tools and methods to remove the carbon paper coating used in the sintering process;

[0048] S5.2. Surface polishing

[0049] Polish the parts to ensure that the surface finish meets the design requirements

[0050] S5.3, Dimensional finishing:

[0051] According to the design drawings, the parts are fine-machined to ensure that the size and shape of the parts meet the requirements.

[0052] Example 2

[0053] This embodiment provides an aluminum-tungsten-copper multi-element alloy and a preparation method thereof. The preparation method is different from that of embodiment 1 in that step S1 is:

[0054] S1. Raw material weighing

[0055] Accurately weigh 14.0 g of aluminum powder (Al), 76.5 g of tungsten powder (W), 11.0 g of copper powder (Cu), 2.0 g of nickel powder (Ni), 1.5 g of molybdenum powder (Mo), 0.8 g of titanium powder (Ti), 0.6 g of zirconium powder (Zr), and 0.4 g of boron powder (B). The purity of all raw materials used should be no less than 99.5%. The particle size of the aluminum, tungsten, and copper powders should be less than 100 μm. The particle size of the other additive element powders (nickel powder, molybdenum powder, titanium powder, zirconium powder, and boron powder) should be less than 75 μm.

[0056] The remaining steps are consistent with those in Example 1.

[0057] The aluminum-tungsten-copper multi-element alloys provided in Examples 1 and 2 were tested to evaluate mechanical properties and performance under actual service conditions. The testing methods included:

[0058] (1) Sample preparation: The aluminum-tungsten-copper multi-element alloys provided in Example 1 and Example 2 were prepared into test samples using a spark plasma sintering process (SPS).

[0059] (2) Mechanical properties test: Perform hardness test on the test samples and measure the Vickers hardness of each group of samples.

[0060] (3) Density test: Conduct density test on the test samples to determine the density of each group of samples.

[0061] The density is measured by the Archimedes drainage method, and the medium is deionized water.

[0062] The final test results are shown in Table 1 and Table 2.

[0063] Table 1

[0064] sample Vickers hardness (HV) Example 1 570 HV Example 2 635 - 665 HV

[0065] Table 2

[0066] sample Theoretical density Actual density density Example 1 9.356 g / cm³ 9.12 g / cm³ 97.4% Example 2 9.547 g / cm³ 9.38 g / cm³ 97.4%

[0067] Table 3 shows the Vickers hardness ranges for standard aluminum alloys (2024, 2219, 2618, 2124, and 7075). These values are typical values reported in literature or referenced in material handbooks under common heat treatment conditions (usually T6 or T4, depending on the alloy grade).

[0068] Table 3

[0069] Alloy model Best Vickers hardness (HV) 2024 aluminum alloy 150-160 HV 2219 aluminum alloy 135-145 HV 2618 aluminum alloy 140-150 HV 2124 aluminum alloy 145-155 HV 7075 aluminum alloy 170-190 HV

[0070] By comparing Table 1 and Table 3, it can be seen that the Vickers hardness of the samples prepared by the aluminum-tungsten-copper multi-element alloys provided in Example 1 and Example 2 is much higher than the Vickers hardness of the conventional aluminum alloy. As can be seen from Table 2, the samples prepared by the aluminum-tungsten-copper multi-element alloys provided in Example 1 and Example 2 also have extremely high density.

[0071] This is because the aluminum-tungsten-copper multi-element alloys provided in Examples 1 and 2 contain up to 70-77 parts by mass of tungsten, making them essentially metal-matrix composites with high-hardness, high-modulus tungsten particles as the primary reinforcement phase. The tungsten phase bears the primary load and hinders matrix deformation, which is the primary source of the high hardness. Secondly, the copper, along with various trace elements such as nickel, molybdenum, titanium, zirconium, and boron, in the alloy further strengthen the aluminum-copper matrix through solid solution strengthening, the formation of dispersed secondary phases (such as intermetallic compounds and borides), and grain refinement. Finally, the fabrication processes employed—mechanical alloying (MA) and spark plasma sintering (SPS)—play a key role: the MA process introduces significant work hardening and refines the grains to ultrafine levels, while the SPS technique achieves rapid densification (achieving a high density of ~97.4%) while effectively suppressing grain growth, thereby maintaining an ultrafine grain structure and ensuring a good bond between the reinforcement phase and the matrix. The combined effect of these factors (high volume fraction hard phase reinforcement, multi-element alloying synergistic strengthening, ultrafine grains and high density) gives the Al-W-Cu alloy a hardness level far exceeding that of traditional precipitation-strengthened aluminum alloys.

[0072] The embodiments of the present invention are described above, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which are all protected by the present invention.

Claims

1. An aluminum-tungsten-copper multi-element alloy, characterized in that: The invention comprises the following components in parts by mass: 13.5 to 17.6 parts of aluminum, 70.0 to 77.0 parts of tungsten, 9.0 to 12.0 parts of copper, 0.3 to 2.5 parts of nickel, 0.1 to 2.0 parts of molybdenum, 0.05 to 1.2 parts of titanium, 0.02 to 0.90 parts of zirconium, 0.02 to 0.65 parts of boron and 0.1 to 0.3 parts of impurity elements; The impurity elements include oxygen, nitrogen, carbon and hydrogen.

2. A method for preparing an aluminum-tungsten-copper multi-element alloy as claimed in claim 1, characterized in that: include: Weigh raw material powders of aluminum, tungsten, copper, nickel, molybdenum, titanium, zirconium and boron in parts by mass, and perform mechanical alloying treatment on the raw material powders; Screening the mechanically alloyed powder to obtain powder with a particle size within a preset particle size range; The powder with a particle size within a preset range is sintered to obtain an aluminum-tungsten-copper multi-element alloy.

3. The aluminum-tungsten-copper multi-element alloy according to claim 2, characterized in that: The particle sizes of the aluminum, tungsten and copper powders in the raw material powders are all less than 100 μm.

4. The aluminum-tungsten-copper multi-element alloy according to claim 2, wherein: The preset particle size range is 10~90μm.

5. The aluminum-tungsten-copper multi-element alloy according to claim 2, characterized in that: The mechanical alloying process is a wet ball milling process, comprising: The weighed raw material powder, zirconium oxide balls, medium and dispersant are placed in a ball mill at a mass ratio of 1:5:(2-3):0.01 and ball milled at a speed of 200-300 rpm for 0.5-2 hours to obtain a ball-milled powder, wherein the medium is anhydrous ethanol and the dispersant is polyethylene glycol PEG; The ball-milled powder was placed in a vacuum drying oven and dried at 60-80°C for 4 hours to obtain the final mechanically alloyed powder.

6. The aluminum-tungsten-copper multi-element alloy according to claim 2, characterized in that: The sintering process includes: Filling powder with a particle size within a preset range into a sintering mold and assembling the sintering mold; Place the assembled sintered abrasive tool in a vacuum environment and pre-press it at a pressure of 20-25 MPa; The temperature was raised to 600-670°C at 100°C / min, the pressure was increased to 40-50 MPa, maintained for 6-12 minutes, and then cooled to room temperature to complete sintering.

7. The aluminum-tungsten-copper multi-element alloy according to claim 6, characterized in that: Carbon paper is laid on the bottom of the sintering mold, and powder with a particle size within a preset range is filled into the sintering mold to form a powder layer. A layer of carbon paper is placed on top of the powder layer, and finally the sintering mold is assembled.

8. The aluminum-tungsten-copper multi-element alloy according to claim 7, characterized in that: After the aluminum-tungsten-copper multi-element alloy is obtained through sintering, the aluminum-tungsten-copper multi-element alloy is subjected to mechanical processing.

9. The aluminum-tungsten-copper multi-element alloy according to claim 8, characterized in that: The mechanical processing includes: Removal of carbon paper from the surface of aluminum-tungsten-copper alloy; Polishing the surface of the aluminum-tungsten-copper multi-element alloy; Processing of aluminum-tungsten-copper multi-element alloys according to preset drawings.