Preparation method of rare earth yttrium-neodymium co-doped reinforced copper-based composite material

Abstract

The invention discloses a preparation method of a rare earth yttrium-neodymium co-doped reinforced copper-based composite material. The preparation method comprises the following steps: a, providing copper powder, titanium carbide powder, yttrium powder and neodymium powder; b, mixing the following components in percentage by mass: 95.0%-98.5% of copper powder, 1.0%-3.0% of titanium carbide powder, 0.2%-1.0% of yttrium powder and 0.3%-1.0% of neodymium powder, and the sum of the contents of all the components is 100%; c, carrying out mechanical alloying pretreatment on the mixed powder in the step b; and d, the pretreated composite powder is placed in a microwave sintering furnace, microwave sintering is conducted under the protective atmosphere or vacuum, the temperature ranges from 750 DEG C to 850 DEG C, the pressure ranges from 20 MPa to 35 MPa, heat preservation is conducted for 10 min to 30 min, and then cooling is conducted to obtain the copper-based composite material. According to the method, a Y-Nd synergistic modification and titanium carbide TiC-rare earth oxide double-phase dispersion strengthening system is constructed, and a microwave-assisted low-temperature sintering process is combined, so that the copper-based composite material with high strength, high conductivity and excellent wear resistance is prepared.

Description

Technical Field

[0001] This invention relates to the field of materials, and in particular to a method for preparing rare earth yttrium-neodymium co-doped reinforced copper-based composite materials. Background Technology

[0002] Copper-based composite materials are key foundational materials supporting the development of industries such as power transmission and intelligent manufacturing. As high-end equipment upgrades towards higher power, miniaturization, and longer lifespan, the comprehensive performance requirements for copper-based materials are becoming increasingly stringent. Their application scenarios have expanded to high-end equipment operating under high-frequency friction and high-temperature conditions, further highlighting the performance shortcomings of existing materials. Current technological status and level: To improve the performance of copper-based materials, the industry has explored various solutions such as rare-earth doping modification and high-temperature sintering. While single rare-earth doping technology can specifically improve material strength or conductivity, it is difficult to simultaneously achieve both core properties. High-temperature sintering (conventional temperature 950~1100℃) is the mainstream forming method. Although it can initially achieve material densification, it suffers from high energy consumption, easily coarse grains, and difficulty in exceeding 92% density. The main problems are concentrated in three main areas: First, there is an inherent contradiction between strength and conductivity, and a single modification method cannot synergistically improve them; second, high-temperature sintering energy consumption accounts for more than 30% of the total preparation cost, and coarse grains further deteriorate conductivity; third, wear resistance is generally insufficient, resulting in rapid wear rates in high-frequency friction scenarios such as motor brushes and conductive terminals, with a service life only meeting the needs of low- to mid-range equipment. Currently, no preparation solution has emerged that can simultaneously solve these three problems, making it difficult for copper-based materials to meet the stringent requirements of high-end equipment and becoming a key bottleneck restricting their large-scale application in high-end fields. Summary of the Invention

[0003] To address the aforementioned shortcomings, the present invention aims to propose a rare-earth yttrium-neodymium (Y-Nd) co-doped reinforced microwave-assisted low-temperature sintering copper-based composite material and its preparation method. This method constructs a Y-Nd synergistic modification and titanium carbide (TiC)-rare-earth oxide biphase dispersion strengthening system, combined with a microwave-assisted low-temperature sintering process, to prepare a copper-based composite material with high strength, high conductivity, and excellent wear resistance.

[0004] To achieve this objective, the present invention adopts the following technical solution: A method for preparing a rare-earth yttrium-neodymium co-doped reinforced copper-based composite material includes the following steps: a. Provide copper powder, titanium carbide powder, yttrium powder, and neodymium powder; b. By mass percentage, mix the following components: 95.0-98.5% copper powder, 1.0-3.0% titanium carbide powder, 0.2-1.0% yttrium powder, and 0.3-1.0% neodymium powder, with the sum of the contents of each component being 100%. c. Perform mechanical alloying pretreatment on the mixed powder from step b; d. The pretreated composite powder is placed in a microwave sintering furnace and sintered under a protective atmosphere or vacuum at a temperature of 750-850℃ and a pressure of 20-35 MPa for 10-30 minutes, followed by cooling to obtain the copper-based composite material.

[0005] Preferably, the mechanical alloying pretreatment in step c is carried out in a planetary ball mill under the protection of high-purity argon gas, with a ball-to-material ratio of 10:1 to 15:1, a rotation speed of 200-350 rpm, and a ball milling time of 2-6 hours.

[0006] Preferably, the microwave sintering in step d has a heating rate of 50-100℃ / min.

[0007] A rare earth Y-Nd co-doped reinforced microwave-assisted low-temperature sintering copper matrix composite material prepared by a method for preparing rare earth Y-Nd co-doped reinforced copper matrix composite material, wherein the matrix is ​​copper and the reinforcing phase includes titanium carbide, in-situ generated Y2O3 and Nd2O3 nanoparticles. The Y2O3 and Nd2O3 nanoparticles are dispersed inside the copper matrix and at the interface between titanium carbide and the copper matrix.

[0008] Preferably, its conductivity is ≥76% IACS and its Vickers hardness is ≥150 HV.

[0009] One of the above technical solutions includes the following beneficial effects: 1. Performance synergy breakthrough: Through Y-Nd rare earth element co-doping, a synergistic effect of "1+1>2" is generated, which not only more effectively purifies the matrix and refines the grains, but also significantly improves the interface bonding between the reinforcing phase and the matrix, breaks through the performance bottleneck of single rare earth modification, and achieves a comprehensive improvement in strength, conductivity and wear resistance.

[0010] 2. Energy-saving and efficient process: The microwave-assisted low-temperature sintering process significantly reduces the sintering temperature from the traditional 900℃ or above to 750-850℃ and greatly shortens the holding time, reducing energy consumption by about 30%-50%. At the same time, it effectively suppresses grain coarsening and unfavorable interface reactions, resulting in a better microstructure.

[0011] 3. Enhanced mechanism innovation: A two-phase dispersion strengthening system of "micron TiC + nano rare earth oxide" was constructed, realizing multi-scale synergistic strengthening. This enabled the composite material to maintain high conductivity (≥ 76% IACS) while its hardness and wear resistance were multiplied, and its comprehensive performance far exceeded that of similar materials prepared by traditional processes. Attached Figure Description

[0012] Figure 1This is a flowchart of the overall steps of an embodiment of the present invention. Detailed Implementation

[0013] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0014] A method for preparing a rare-earth yttrium-neodymium co-doped reinforced copper-based composite material includes the following steps: a. Provide copper powder, titanium carbide powder, yttrium powder, and neodymium powder; b. By mass percentage, mix the following components: 95.0-98.5% copper powder, 1.0-3.0% titanium carbide powder, 0.2-1.0% yttrium powder, and 0.3-1.0% neodymium powder, with the sum of the contents of each component being 100%. c. Perform mechanical alloying pretreatment on the mixed powder from step b; d. The pretreated composite powder is placed in a microwave sintering furnace and microwave sintered at a temperature of 750-850℃ and a pressure of 20-35 MPa under a protective atmosphere or vacuum for 10-30 minutes, and then cooled to obtain the copper-based composite material.

[0015] Performance synergy breakthrough: Through Y-Nd rare earth element co-doping, a synergistic effect of "1+1>2" is generated, which not only more effectively purifies the matrix and refines the grains, but also significantly improves the interface bonding between the reinforcing phase and the matrix, breaking through the performance bottleneck of single rare earth modification and achieving a comprehensive improvement in strength, conductivity and wear resistance.

[0016] The mechanical alloying pretreatment in step c is carried out in a planetary ball mill under the protection of high-purity argon gas, with a ball-to-material ratio of 10:1 to 15:1, a rotation speed of 200-350 rpm, and a ball milling time of 2-6 hours.

[0017] In step d, the microwave sintering has a heating rate of 50-100℃ / min.

[0018] A rare earth Y-Nd co-doped reinforced microwave-assisted low-temperature sintering copper matrix composite material prepared by a method for preparing rare earth Y-Nd co-doped reinforced copper matrix composite material, wherein the matrix is ​​copper and the reinforcing phase includes titanium carbide, in-situ generated Y2O3 and Nd2O3 nanoparticles. The Y2O3 and Nd2O3 nanoparticles are dispersed inside the copper matrix and at the interface between titanium carbide and the copper matrix.

[0019] In addition, its conductivity is ≥76% IACS and its Vickers hardness is ≥150 HV.

[0020] The technical solution is as follows: (a) Material preparation Copper powder: purity ≥99.9%, particle size 1-10 μm; Titanium carbide powder: purity ≥99.5%, particle size 50-200 nm; Yttrium powder: purity ≥99.5%, particle size 1-5 μm; Neodymium powder: purity ≥99.5%, particle size 1-5 μm (II) Preparation steps Step 1: Mechanical alloying pretreatment Weigh the following raw materials by mass percentage: 95.0-98.5% copper powder, 1.0-3.0% titanium carbide powder, 0.2-1.0% yttrium powder, and 0.3-1.0% neodymium powder. The sum of the contents of each component is 100%.

[0021] The mixed powder and cemented carbide grinding balls under high-purity argon protection are placed together in a planetary ball mill with a ball-to-powder ratio of 10:1 to 15:1, a rotation speed of 200-350 rpm, and a milling time of 2-6 hours. This process aims to achieve preliminary alloying and uniform mixing of the powder.

[0022] Step 2: Microwave-assisted low-temperature sintering The ball-milled composite powder is loaded into a graphite mold and sintered in a microwave sintering furnace protected by vacuum or high-purity argon.

[0023] Sintering process parameters: sintering temperature is 750-850℃ (significantly lower than the traditional sintering temperature), heating rate is 50-100℃ / min, holding time is 10-30 minutes, and axial pressure of 20-35 MPa is applied simultaneously.

[0024] A graphene layer is grown in situ on the surface of Cu-SiC composite powder to form Gr-Cu-SiC composite powder.

[0025] Step 3: Follow-up processing After sintering, the material is cooled to room temperature in the furnace and then demolded to obtain the composite material preform.

[0026] The blank can be machined as necessary to obtain the finished product with the required shape and size. Example

[0027] Raw materials: electrolytic copper powder (particle size ~5 μm), nano TiC powder (particle size ~100 nm), Y powder (particle size ~3 μm), Nd powder (particle size ~3 μm).

[0028] Ingredients: Weigh by weight percentage: 97.0% copper powder, 1.5% TiC powder, 0.5% Y powder, and 1.0% Nd powder.

[0029] Ball milling: Place the mixed powder in a planetary ball mill and mill for 4 hours under the protection of high-purity argon gas at a ball-to-powder ratio of 12:1 and a rotation speed of 300 rpm.

[0030] Sintering: The ball-milled powder was loaded into a graphite mold with BN release agent on the inner wall and placed in a microwave sintering furnace. After evacuating to 10⁻² Pa, high-purity argon was introduced as a protective atmosphere. The temperature was increased to 800℃ at a rate of 80 ℃ / min, and a pressure of 25 MPa was applied and held for 20 minutes.

[0031] Cooling: After the heat preservation is completed, heating is stopped, and the sample is cooled to room temperature under pressure in the furnace. The sample is then demolded to obtain a composite material sample with a diameter of 30 mm × 5 mm. Example

[0032] Raw materials: electrolytic copper powder (particle size ~5 μm), nano TiC powder (particle size ~100 nm), Y powder (particle size ~3 μm), Nd powder (particle size ~3 μm).

[0033] Ingredients: Weigh by weight percentage: 96.2% copper powder, 2.0% TiC powder, 0.8% Y powder, and 1.0% Nd powder.

[0034] Ball milling: Place the mixed powder in a planetary ball mill and mill for 4 hours under the protection of high-purity argon gas at a ball-to-powder ratio of 12:1 and a rotation speed of 300 rpm.

[0035] Sintering: The ball-milled powder was loaded into a graphite mold with BN release agent on the inner wall and placed in a microwave sintering furnace. After evacuating to 10⁻² Pa, high-purity argon was introduced as a protective atmosphere. The temperature was increased to 780℃ at a rate of 78 ℃ / min, and a pressure of 25 MPa was applied and held for 25 minutes.

[0036] Cooling: After the heat preservation is completed, heating is stopped, and the sample is cooled to room temperature under pressure in the furnace. The sample is then demolded to obtain a composite material sample with a diameter of 30 mm × 5 mm.

[0037] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A method for preparing a rare-earth yttrium-neodymium co-doped reinforced copper-based composite material, characterized in that, Includes the following steps: a. Provide copper powder, titanium carbide powder, yttrium powder, and neodymium powder; b. By mass percentage, mix the following components: 95.0-98.5% copper powder, 1.0-3.0% titanium carbide powder, 0.2-1.0% yttrium powder, and 0.3-1.0% neodymium powder, with the sum of the contents of each component being 100%. c. Perform mechanical alloying pretreatment on the mixed powder from step b; d. The pretreated composite powder is placed in a microwave sintering furnace and microwave sintered at a temperature of 750-850℃ and a pressure of 20-35 MPa under a protective atmosphere or vacuum for 10-30 minutes, and then cooled to obtain the copper-based composite material.

2. The method for preparing rare earth yttrium-neodymium co-doped reinforced copper-based composite material according to claim 1, characterized in that, The mechanical alloying pretreatment in step c is carried out in a planetary ball mill under the protection of high-purity argon gas, with a ball-to-material ratio of 10:1 to 15:1, a rotation speed of 200-350 rpm, and a ball milling time of 2-6 hours.

3. The method for preparing rare earth yttrium-neodymium co-doped reinforced copper-based composite material according to claim 1, characterized in that, The microwave sintering in step d has a heating rate of 50-100℃ / min.

4. A rare-earth Y-Nd co-doped reinforced microwave-assisted low-temperature sintering copper-based composite material prepared by the method according to any one of claims 1-3, characterized in that, Its matrix is ​​copper, and the reinforcing phase includes titanium carbide, in-situ generated Y2O3 and Nd2O3 nanoparticles; The Y2O3 and Nd2O3 nanoparticles are dispersed inside the copper matrix and at the interface between titanium carbide and the copper matrix.

5. The copper-based composite material according to claim 4, characterized in that, Its conductivity is ≥76% IACS and its Vickers hardness is ≥150 HV.

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