Preparation method of SnO2@In2O3CuO reinforced silver-based composite material

Abstract

The present invention discloses a method for preparing a SnO2@In2O3CuO-reinforced silver-based composite material. The method utilizes an in-situ reaction synthesis technique to obtain the SnO2@In2O3CuO-reinforced silver-based composite material. High-energy ball milling is first used to obtain a SnO2@InCu core-shell structure. The SnO2@In2O3CuO-reinforced silver-based composite material is then synthesized and sintered in-situ to obtain the SnO2@In2O3CuO-reinforced silver-based composite material. The composite material strip or wire is then obtained through extrusion, rolling, or drawing. The method's greatest advantage lies in its ability to produce the SnO2@In2O3CuO core-shell structure-reinforced silver-based composite material through in-situ reaction synthesis. The resulting composite material exhibits a clean interface and strong interfacial bonding, maximizing the synergistic effect of the core-shell structure. Ultimately, the SnO2@In2O3CuO-reinforced silver-based composite material exhibits excellent mechanical properties and substantially no reduction in electrical conductivity.

Description

Technical Field

[0001] The invention relates to a preparation method of a SnO2@In2O3CuO reinforced silver-based composite material, belonging to the field of new electronic information materials. Background Art

[0002] The contact materials used in low-voltage electrical switches are primarily silver-based composites. The earliest developed and applied Ag / CdO electrical contact materials are restricted by the EU's ROS Directive due to the presence of the element Cd, which can cause environmental pollution and harm human health. There is an urgent need to develop new, environmentally friendly silver-based composites with enhanced microstructures.

[0003] Currently, the preparation processes for silver metal oxide composite materials on the market include: powder metallurgy, internal alloy oxidation, and powder pre-oxidation. Powder metallurgy is the most basic preparation process for silver metal oxide materials. It has a simple process, is relatively easy to add elements, and is not restricted by material components. However, the simple powder mixing process makes it difficult to ensure the uniform distribution of the reinforcing phase in the silver matrix. In addition, the raw materials are easily contaminated by the outside world during the preparation process and have many defects, which leads to deterioration of the material's electrical contact performance. Silver metal oxide materials prepared by the internal alloy oxidation method often suffer from incomplete oxidation, which affects the material's performance. The powder pre-oxidation method is also a type of powder metallurgy method, which also has the disadvantages that the raw materials are easily contaminated by the outside world and have many defects, which leads to deterioration of the material's electrical contact performance.

[0004] Based on the above industry background, the present invention proposes a method for preparing a core-shell structured metal oxide reinforced silver-based material using in-situ reaction synthesis preparation technology; the advantage of this preparation method is that it can utilize existing traditional preparation equipment, does not require secondary investment by the enterprise, and can obtain excellent mechanical properties. Summary of the Invention

[0005] The present invention aims to provide a method for preparing a SnO2@In2O3CuO reinforced silver-based composite material, which improves the interface wettability of the SnO2 reinforced silver-based composite material through the SnO2@In2O3CuO core-shell structure, thereby improving the processing performance and yield rate of the silver-based composite material; the obtained SnO2@In2O3CuO reinforced silver-based composite material has excellent mechanical properties, and specifically comprises the following steps:

[0006] (1) Under inert gas protection, commercially available nano-SnO2 was mixed with copper powder and indium in proportion and then ball milled in a high-energy ball mill to obtain SnO2@InCu powder.

[0007] (2) The SnO2@InCu powder is then mixed evenly with silver powder and silver oxide powder in proportion, pressed into an ingot, and then sintered in an in-situ reaction sintering furnace to obtain a SnO2@In2O3CuO reinforced silver-based composite material sintered billet.

[0008] (3) Finally, the sintered blank is densified, extruded, drawn, or rolled to prepare wire or strip.

[0009] Preferably, the commercially available nano-SnO2 powder of the present invention has a particle size of 40-80 nm and a purity of 99.9%; the copper powder and indium powder have a particle size of 0.5-50 μm and a purity of 99.9%; the silver powder has a particle size of 10-80 μm and a purity of 99.9%; and the silver oxide powder has a particle size of 10-50 μm and a purity of 99.9%.

[0010] Preferably, in the present invention, after nano-SnO2 is mixed with indium powder and copper powder at a SnO2:InCu mass ratio of (10-12):(0.5-4.5), the mass ratio of indium powder and copper powder is prepared according to actual needs, wherein the mass ratio of copper powder and indium powder is 1:1.

[0011] Preferably, the ball milling conditions in step (1) of the present invention are: ball milling at a rotation speed of 400-800 r / min for 0.5-3 h under the protection of inert argon.

[0012] Preferably, in step (2) of the present invention, the SnO2@InCu powder, silver powder and silver oxide powder are prepared so as to generate SnO2@In2O3CuO with a mass percentage of 12%-18% in the silver matrix.

[0013] Preferably, the specific method of uniform mixing of the present invention is to ball mill at a rotation speed of 100-500 r / min for 0.5-2 h to obtain a uniformly mixed composite powder.

[0014] Preferably, the conditions for pressing into ingots according to the present invention are 150-500MPa, and the sintering conditions are: 100-200°C, keeping warm for 1-2h, then heating to 300-500°C, keeping warm for 1-2h, and finally heating to 830-850°C, keeping warm for 0.5-3h.

[0015] The beneficial effects of the present invention are as follows: compared with traditional silver metal oxides, the present invention prepares a SnO2@In2O3CuO core-shell structured metal oxide reinforced silver-based composite material; compared with the AgSnO2 composite material, the composite material not only improves the interface wettability between SnO2 and silver, improves the processing performance of the composite material, but also obtains a SnO2@In2O3CuO core-shell structure reinforced silver-based composite material with excellent mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a process flow chart of the present invention.

[0017] Figure 2This is a high-resolution transmission electron microscopy image of the prepared SnO2@In2O3CuO core-shell structure reinforced silver-based composite material. Specific implementation plan

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the protection content of the present invention is not limited to the scope described in the embodiments.

[0019] Example 1

[0020] A method for preparing SnO2@In2O3CuO reinforced silver-based composite material, such as Figure 1 As shown, the specific steps include:

[0021] (1) Commercially available nano-SnO2 and copper powder were mixed in a ratio of SnO2:InCu = 12:2.5 (mass ratio), and then ball milled at a speed of 500 r / min for 1.5 h under inert argon protection to obtain SnO2@InCu powder.

[0022] (2) Then, SnO2@InCu powder was prepared with silver powder and silver oxide powder according to the formation of 14.7% (mass percentage) SnO2@In2O3CuO in the silver matrix, and ball milled at a speed of 300 r / min for 1 h to obtain a uniformly mixed composite powder.

[0023] (3) The composite powder was then loaded into a mold and formed under a pressing pressure of 350 MPa. The formed ingot was placed in an in-situ reaction sintering furnace and sintered according to the sintering process of 100°C (keeping warm for 1 hour) → 300°C (keeping warm for 1 hour) → 830°C (keeping warm for 1 hour) to obtain a SnO2@In2O3CuO reinforced silver-based composite material sintered billet.

[0024] (4) Finally, the sintered blank is densified, extruded and drawn to prepare wire.

[0025] The tensile strength of the SnO2@In2O3CuO reinforced silver-based composite material prepared in this embodiment reaches 380 MPa.

[0026] Comparative Example 1

[0027] Commercially available nano-SnO2 was prepared with silver powder and silver oxide powder in such a manner that 14.7% (mass percentage) of SnO2 was generated in the silver matrix, and ball milling was performed at a rotation speed of 300 r / min for 1 h to obtain a uniformly mixed composite powder.

[0028] (3) The composite powder is then loaded into a mold and formed under a pressing pressure of 350 MPa. The formed ingot is placed in an in-situ reaction sintering furnace and sintered according to the sintering process of 100°C (keeping warm for 1 hour) → 300°C (keeping warm for 1 hour) → 830°C (keeping warm for 1 hour) to obtain a SnO2 reinforced silver-based composite material sintered ingot.

[0029] The tensile strength of the AgSnO2 composite material prepared in this embodiment can reach 345 MPa.

[0030] By comparison, it can be seen that, compared with the AgSnO2 composite material, the present invention can improve the interface wettability between silver and SnO2, obtain a core-shell structure with a strong interface bonding, and greatly improve the mechanical properties and processing properties of the composite material.

[0031] Example 2

[0032] A method for preparing SnO2@In2O3CuO reinforced silver-based composite material, such as Figure 1 As shown, the specific steps include:

[0033] (1) Commercially available nano-SnO2 and copper powder were mixed in a ratio of SnO2:InCu = 12:0.5 (mass ratio), and then ball-milled at a speed of 400 r / min for 3 h under the protection of inert argon to obtain SnO2@InCu powder.

[0034] (2) Then, SnO2@InCu powder was prepared with silver powder and silver oxide powder according to the formation of 13% (mass percentage) of SnO2@In2O3CuO in the silver matrix, and ball milled at a speed of 200 r / min for 2 h to obtain a uniformly mixed composite powder.

[0035] (3) The composite powder is then loaded into a mold and formed under a pressing pressure of 500 MPa. The formed ingot is placed in an in-situ reaction sintering furnace and sintered according to the sintering process of 150°C (keeping warm for 1 hour) → 360°C (keeping warm for 1 hour) → 840°C (keeping warm for 1 hour) to obtain a SnO2@In2O3CuO reinforced silver-based composite material sintered ingot.

[0036] (4) Finally, the sintered blank is densified and rolled to prepare a strip.

[0037] The tensile strength of the SnO2@In2O3CuO reinforced silver-based composite material prepared in this example reaches 395 MPa.

[0038] Example 3

[0039] A method for preparing SnO2@In2O3CuO reinforced silver-based composite material, such as Figure 1 As shown, the specific steps include:

[0040] (1) Commercially available nano-SnO2 and copper powder were mixed in a ratio of SnO2:InCu = 12:3.5 (mass ratio), and then ball milled at a speed of 800 r / min for 0.5 h under inert argon protection to obtain SnO2@InCu powder.

[0041] (2) Then, SnO2@InCu powder was prepared with silver powder and silver oxide powder so as to generate 16% (mass percentage) of SnO2@In2O3CuO in the silver matrix, and ball milled at a speed of 500 r / min for 0.5 h to obtain a uniformly mixed composite powder.

[0042] (3) The composite powder is then loaded into a mold and formed under a pressing pressure of 500 MPa. The formed ingot is placed in an in-situ reaction sintering furnace and sintered according to the sintering process of 200°C (keeping for 2 h) → 500°C (keeping for 1 h) → 850°C (keeping for 0.5 h) to obtain a SnO2@In2O3CuO reinforced silver-based composite material sintered blank.

[0043] (4) Finally, the sintered blank is densified, extruded and drawn to prepare wire.

[0044] The tensile strength of the SnO2@In2O3CuO reinforced silver-based composite material prepared in this example reaches 394 MPa.

[0045] Example 4

[0046] A method for preparing SnO2@CuO reinforced silver-based composite material, such as Figure 1 As shown, the specific steps include:

[0047] (1) Commercially available nano-SnO2 and copper powder were mixed in a ratio of SnO2:InCu = 10:4.5 (mass ratio), and then ball-milled at a speed of 600 r / min for 3 h under the protection of inert argon to obtain SnO2@InCu powder.

[0048] (2) Then, SnO2@InCu powder was prepared with silver powder and silver oxide powder according to the formation of 16% (mass percentage) of SnO2@In2O3CuO in the silver matrix, and ball milled at a speed of 400 r / min for 1 h to obtain a uniformly mixed composite powder.

[0049] (3) The composite powder is then loaded into a mold and formed under a pressing pressure of 500 MPa. The formed ingot is placed in an in-situ reaction sintering furnace and sintered according to the sintering process of 100°C (keeping for 2 hours) → 380°C (keeping for 1 hour) → 830°C (keeping for 3 hours) to obtain a SnO2@In2O3CuO reinforced silver-based composite material sintered blank.

[0050] (4) Finally, the sintered blank is densified and rolled to prepare a strip.

[0051] The tensile strength of the SnO2@In2O3CuO reinforced silver-based composite material prepared in this example reaches 396 MPa.

Claims

1. A method for preparing a SnO2@In2O3CuO reinforced silver-based composite material, characterized in that: Specifically include the following steps: (1) Under inert gas protection, commercially available nano-SnO2 was mixed with copper powder and indium powder in proportion and then ball milled in a high-energy ball mill to obtain SnO2@InCu powder; (2) The SnO2@InCu powder is then mixed evenly with silver powder and silver oxide powder in proportion, pressed into an ingot, and then sintered in an in-situ reaction sintering furnace to obtain a SnO2@In2O3CuO reinforced silver-based composite material sintered billet; (3) Finally, the sintered blank is densified, extruded, drawn, or rolled to prepare a wire or strip; The particle size of commercially available nano SnO2 powder is 40-80nm, the particle size of copper powder and indium powder is 0.5-50µm, the particle size of silver powder is 10-80µm, and the particle size of silver oxide powder is 10-50µm; Mix nano-SnO2 with indium powder and copper powder at a SnO2:InCu mass ratio of (10-12):(0.5-4.5), where the mass ratio of copper powder to indium powder is 1:1; The ball milling conditions in step (1) are: ball milling at a speed of 400-800 r / min for 0.5-3 h under the protection of inert argon; In step (2), the SnO2@InCu powder, silver powder and silver oxide powder are prepared so as to generate SnO2@In2O3CuO with a mass percentage of 12%-18% in the silver matrix; The specific method of uniform mixing is to ball mill at a rotation speed of 100-500 r / min for 0.5-2 h to obtain a uniformly mixed composite powder.

2. The method for preparing the SnO2@In2O3CuO reinforced silver-based composite material according to claim 1, characterized in that: The purity of commercially available nano-SnO2 powder is 99.9%; the purity of copper powder and indium powder is 99.9%; the purity of silver powder is 99.9%; and the purity of silver oxide powder is 99.9%.

3. The method for preparing the SnO2@In2O3CuO reinforced silver-based composite material according to claim 1, characterized in that: The conditions for pressing into ingots are 150-500MPa.

4. The method for preparing the SnO2@In2O3CuO reinforced silver-based composite material according to claim 1, characterized in that: The sintering conditions are: 100~200℃, keep warm for 1~2h, then heat up to 300~500℃, keep warm for 1~2h, and finally heat up to 830~850℃, keep warm for 0.5~3h.

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