Preparation method for improving Cu-Ta alloy performance by adding third alloy element

Abstract

The invention discloses a preparation method for improving Cu-Ta alloy performance by adding a third alloy element, and relates to the technical field of copper alloy material preparation. According to the preparation method, Cu-Ta-M mixed powder is prepared by carrying out mechanical alloying on Cu-M atomized powder, copper powder and tantalum powder, then the Cu-Ta-M copper-based composite material is prepared through spark plasma sintering, and M is one of Cr, Zr and Y. The Cu-M alloy powder prepared through the atomization technology is uniform in powder component and small in particle size, large driving force is achieved in the sintering process, and alloy components obtained after sintering are uniform. By introducing a third alloy element M into the Cu-Ta alloy, the grain structure of the alloy is effectively refined, segregation of Ta is reduced, and the physical performance of the Cu-Ta alloy is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of copper alloy material preparation, and in particular to a preparation method for improving the performance of a Cu-Ta alloy by adding a third alloy element. Background Art

[0002] Advanced copper-based composites have received increasing attention in the field of electrical contact materials such as electrode materials and ultra-large-scale integrated circuits because they are the most likely to achieve an excellent combination of strength, toughness and conductive properties.

[0003] Cu-Ta composites are widely used due to their high hardness, high tensile strength, and excellent electrical conductivity. The high thermal stability and outstanding tensile strength of Cu-Ta alloys have been demonstrated to be attributed to well-dispersed Ta clusters and nanoscale Ta precipitates, which provide strong resistance to grain boundary migration and ultimately prevent grain growth via a Zener pinning mechanism. Mechanical alloying has been shown to be a simple and effective method for preparing Cu-Ta alloys because it can utilize high energy to force the formation of a metastable solution with higher solid solubility between Cu and Ta. However, because Cu and Ta are poorly soluble in each other, Ta atoms diffuse very slowly within the Cu lattice, and Ta atoms tend to segregate at grain boundaries, which increases the brittleness of Cu-Ta alloys and deteriorates their performance. To ensure the service life of composites, it is necessary to reduce segregation in Cu-Ta alloys.

[0004] In view of the above phenomenon, the present invention attempts to add a third alloying element and adopts a mechanical alloying process to prepare a Cu-Ta alloy with excellent physical properties. Summary of the Invention

[0005] In order to solve the above-mentioned defects existing in the traditional preparation method, the present invention proposes a preparation method for improving the performance of Cu-Ta alloy by adding a third alloying element. This method can refine the Cu-Ta grains and reduce the segregation of Ta atoms during the mechanical alloying process, thereby improving the physical properties of the alloy.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is:

[0007] A preparation method for improving the performance of a Cu-Ta alloy by adding a third alloying element, comprising mechanically alloying atomized Cu-M powder with copper powder and tantalum powder to obtain a Cu-Ta-M mixed powder, and then preparing a Cu-Ta-M copper-based composite material by spark plasma sintering, wherein M is one of Cr, Zr and Y.

[0008] As a preferred technical solution of the present invention, the preparation method specifically comprises the following steps:

[0009] (1) Mechanical alloying: Cu-M powder is prepared by atomization, and then the Cu-M powder is mixed with Cu powder and Ta powder, and the mixed powder is mechanically alloyed to obtain Cu-Ta-M alloy powder;

[0010] Mechanical alloying was carried out under argon atmosphere using stainless steel balls, a high-energy ball milling speed of 400 rpm, a ball-to-material ratio of 10:1, a process control agent of 2 wt.% ethanol, and a ball milling time of 36 h.

[0011] (2) Spark plasma sintering: The Cu-Ta-M alloy powder obtained in step (1) is wrapped with carbon paper and placed in a graphite mold. After pre-pressing, the mold is placed in a spark plasma sintering furnace. The furnace chamber is evacuated to a vacuum at room temperature, a pre-pressing pressure of 10 MPa is set, and the temperature is increased to 900°C and kept warm for 10 minutes. During the temperature increase process, the pressure is uniformly increased to a final pressure of 50 MPa. After the insulation is completed, the powder is cooled to room temperature with the furnace to obtain a Cu-Ta-M alloy. The mass percentage of each element is: Ta 1.5%, M 0.1%-0.3%, and the remainder is copper and inevitable impurities.

[0012] As a further preferred technical solution of the present invention, in the preparation method:

[0013] The purity of the Cu powder used in step (1) is 99.99%, and the powder particle size is less than 45 μm. The particle size of the Cu-M powder obtained by atomization is less than 45 μm. The purity of the Ta powder is 99.9%, and the powder particle size is less than 45 μm.

[0014] The spark plasma sintering heating rate in step (2) is 100°C / min.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] First, the Cu-M (M is one of Cr, Zr and Y) alloy powder prepared by the atomization process of the present invention has uniform powder composition and small particle size, has a large driving force during the sintering process, and the alloy composition obtained after sintering is uniform.

[0017] Secondly, the present invention effectively refines the grain structure of the alloy, reduces the segregation of Ta, and improves the physical properties of the Cu-Ta alloy by introducing a third alloying element M (M is one of Cr, Zr, and Y) into the Cu-Ta alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 1 is a graph showing the electrical conductivity test results of the Cu-Ta alloy prepared in the comparative example of the present invention and the Cu-Ta-M alloy prepared in Examples 1, 2 and 3.

[0019] Figure 2 1 is a graph showing the tensile strength test results of the Cu-Ta alloy prepared in the comparative example of the present invention and the Cu-Ta-M alloys prepared in Examples 1, 2 and 3.

[0020] Figure 3 This is an energy spectrum analysis diagram of the Cu-Ta alloy prepared in the comparative example of the present invention.

[0021] Figure 4 This is an energy spectrum analysis diagram of the Cu-Ta-Cr alloy prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0022] The preferred embodiments and comparative examples of the present invention are described in detail below so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0023] Comparative Example

[0024] The Cu-Ta alloy of this comparative example is composed of the following elements by weight: Ta 1.5%, the remainder being copper and unavoidable impurities. The preparation method comprises the following steps:

[0025] (1) Weigh the exact mass of raw powders according to the desired alloy composition, with a purity of 99.99% Cu powder and 99.9% Ta powder. Load the raw powders into a ball mill with stainless steel balls under an argon atmosphere, with a ball-to-material ratio of 10:1. Use ethanol as a process control agent, adding 2 wt.%. Next, ball mill the Cu powder and 1.5 wt.% Ta powder at 400 rpm for 36 h to obtain a Cu-Ta alloy powder.

[0026] (2) Wrap the Cu-Ta alloy powder obtained in step (1) with carbon paper and put it into a graphite mold. After pre-pressing, put the mold into a discharge plasma furnace. Evacuate the furnace chamber to vacuum at room temperature, set the pre-pressure to 10 MPa, increase the temperature to 900°C and keep it warm for 10 minutes. During the temperature increase process, uniformly pressurize it to a final pressure of 50 MPa. After the insulation is completed, cool it to room temperature with the furnace to obtain a Cu-Ta alloy.

[0027] Example 1

[0028] The composition of the Cu-Ta-Cr alloy of this embodiment consists of the following elements in percentage by mass: Ta 1.5%, Cr 0.3%, and the remainder being copper and inevitable impurities.

[0029] (1) Mechanical alloying:

[0030] Weigh the powder raw materials of accurate mass according to the required alloy composition: Cu powder with a particle size of less than 45μm (purity 99.99%), Cu-Cr powder prepared by gas atomization with a particle size of less than 45μm, and Ta powder with a particle size of less than 45μm (purity 99.9%).

[0031] Cu-Cr powder, Cu powder, Ta powder, and stainless steel balls were placed in a ball mill with a ball-to-material ratio of 10:1. Ethanol was selected as a process control agent at a dosage of 2 wt.%. The powder was then ball milled at 400 rpm for 36 h to obtain a Cu-Ta-Cr alloy powder.

[0032] (2) Spark plasma sintering:

[0033] The Cu-Ta-Cr alloy powder obtained in step (1) is wrapped with carbon paper and loaded into a graphite mold. After pre-pressing, the mold is placed in a discharge plasma furnace. The furnace chamber is evacuated to vacuum at room temperature, a pre-pressure of 10 MPa is set, the temperature is increased to 900°C and kept warm for 10 minutes, and the pressure is uniformly increased to a final pressure of 50 MPa during the temperature increase process. After the insulation is completed, the Cu-Ta-Cr alloy is cooled to room temperature with the furnace to obtain the Cu-Ta-Cr alloy.

[0034] Example 2

[0035] The composition of the Cu-Ta-Zr alloy of this embodiment consists of the following elements in percentage by mass: Ta 1.5%, Zr 0.2%, and the remainder being copper and inevitable impurities.

[0036] (1) Mechanical alloying:

[0037] Weigh the powder raw materials of accurate mass according to the required alloy composition: Cu powder with a particle size of less than 45μm (purity 99.99%), Cu-Zr powder prepared by water atomization with a particle size of less than 45μm, and Ta powder with a particle size of less than 45μm (purity 99.9%).

[0038] Cu-Zr powder, Cu powder, Ta powder, and stainless steel balls were placed in a ball mill with a ball-to-material ratio of 10:1. Ethanol was selected as a process control agent at a dosage of 2 wt.%. The powder was then ball milled at 400 rpm for 36 h to obtain a Cu-Ta-Zr alloy powder.

[0039] (2) Spark plasma sintering:

[0040] The Cu-Ta-Zr alloy powder obtained in step (1) is wrapped with carbon paper and loaded into a graphite mold. After pre-pressing, the mold is placed in a discharge plasma furnace. The furnace chamber is evacuated to a vacuum at room temperature, a pre-pressure of 10 MPa is set, the temperature is increased to 900°C and kept warm for 10 minutes, and the pressure is uniformly increased to a final pressure of 50 MPa during the temperature increase process. After the insulation is completed, the Cu-Ta-Zr alloy is cooled to room temperature with the furnace to obtain the Cu-Ta-Zr alloy.

[0041] Example 3

[0042] The composition of the Cu-Ta-Y alloy of this embodiment is composed of the following elements in percentage by mass: Ta 1.5%, Y 0.1%, and the remainder being copper and inevitable impurities.

[0043] (1) Mechanical alloying:

[0044] Weigh the powder raw materials of accurate mass according to the required alloy composition: Cu powder with a particle size of less than 45μm (purity 99.99%), Cu-Y powder prepared by gas atomization with a particle size of less than 45μm, and Ta powder with a particle size of less than 45μm (purity 99.9%).

[0045] Cu-Y powder, Cu powder, Ta powder, and stainless steel balls were placed in a ball mill at a ball-to-material ratio of 10:1. Ethanol was selected as a process control agent at a dosage of 2 wt.%. The powder was then ball milled at 400 rpm for 36 h to obtain a Cu-Ta-Y alloy powder.

[0046] (2) Spark plasma sintering:

[0047] The Cu-Ta-Y alloy powder obtained in step (1) is wrapped with carbon paper and loaded into a graphite mold. After pre-pressing, the mold is placed in a discharge plasma furnace. The furnace chamber is evacuated to a vacuum at room temperature, a pre-pressure of 10 MPa is set, the temperature is increased to 900°C and kept warm for 10 minutes, and the pressure is uniformly increased to a final pressure of 50 MPa during the temperature increase process. After the insulation is completed, the Cu-Ta-Y alloy is cooled to room temperature with the furnace to obtain the Cu-Ta-Y alloy.

[0048] Depend on Figure 1 、 Figure 2 It can be seen that compared with the Cu-Ta alloy prepared in the comparative example, the alloys prepared by adding the third alloying element in Examples 1, 2, and 3 have more excellent comprehensive properties.

[0049] Depend on Figure 3 、 Figure 4 It can be seen that the addition of alloying elements reduces the segregation of Ta elements and enhances the electrical conductivity and tensile strength of the alloy.

[0050] The above content is merely an example and explanation of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A preparation method for improving the performance of Cu-Ta alloy by adding a third alloying element, characterized in that: The Cu-Ta-M mixed powder is prepared by mechanically alloying Cu-M atomized powder with copper powder and tantalum powder, and then a Cu-Ta-M copper-based composite material is prepared by spark plasma sintering, wherein M is one of Cr, Zr and Y.

2. The preparation method according to claim 1, wherein The specific steps include: (1) Mechanical alloying: Cu-M powder is prepared by atomization, and then the Cu-M powder is mixed with Cu powder and Ta powder, and the mixed powder is mechanically alloyed to obtain Cu-Ta-M alloy powder; Mechanical alloying was carried out under argon atmosphere using stainless steel balls, a high-energy ball milling speed of 400 rpm, a ball-to-material ratio of 10:1, a process control agent of 2 wt.% ethanol, and a ball milling time of 36 h. (2) Spark plasma sintering: The Cu-Ta-M alloy powder obtained in step (1) is wrapped with carbon paper and placed in a graphite mold. After pre-pressing, the mold is placed in a spark plasma sintering furnace. The furnace chamber is evacuated to a vacuum at room temperature, and a pre-pressure of 10 MPa is set. The temperature is increased to 900°C and kept warm for 10 minutes. During the temperature increase process, the pressure is uniformly increased to a final pressure of 50 MPa. After the insulation is completed, the powder is cooled to room temperature with the furnace to obtain a Cu-Ta-M alloy.

3. The preparation method according to claim 2, wherein The purity of the Cu powder used in step (1) is 99.99%, and the powder particle size is less than 45 μm. The particle size of the Cu-M powder obtained by atomization is less than 45 μm. The purity of the Ta powder is 99.9%, and the powder particle size is less than 45 μm.

4. The preparation method according to claim 2, wherein The spark plasma sintering heating rate in step (2) is 100°C / min.

5. The preparation method according to any one of claims 1 to 4, characterized in that The mass percentages of the elements in the prepared Cu-Ta-M alloy are as follows: Ta 1.5%, M 0.1%-0.3%, and the remainder being copper and inevitable impurities.

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