CN102676867B - Alumina particle dispersion strengthened copper composite material and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of electronic materials, and specifically discloses an aluminum oxide particle dispersion-strengthened copper composite material and a preparation method thereof. The chemical composition of the aluminum oxide particle dispersion strengthened copper composite material is: 0.05-1.5% by weight of α-Al ₂ O ₃ , 0.38-0.94% by weight of γ-Al ₂ O ₃ , balance of copper. The preparation method of the aluminum oxide particle dispersion-strengthened copper composite material provided by the present invention has the advantages of short internal oxidation time, low cost and high efficiency, and the prepared alumina particle dispersion-strengthened copper composite material has high strength, high conductivity, high resistance The softening temperature and high temperature strength can meet the requirements of the microelectronics industry and the electronic information industry for high-conductivity, high-strength, and high-temperature-resistant copper alloys, and are widely used in the machinery industry, national defense industry, and electronic information industry.

Description

A kind of aluminum oxide particle dispersion strengthened copper composite material and its preparation method

technical field

The invention relates to the technical field of electronic materials, in particular to an aluminum oxide particle dispersion strengthened copper composite material and a preparation method thereof.

Background technique

The conductivity, strength and high-temperature performance of pure copper and existing grades of copper alloy materials are often difficult to balance, and cannot fully meet the requirements for comprehensive performance of the rapid development of aviation, aerospace, microelectronics and other high-tech. Al ₂ O ₃ dispersion strengthened copper (Cu-Al ₂ O ₃ ) composite material not only maintains the high electrical and thermal conductivity of the copper matrix, but also has superior high temperature performance and corrosion resistance. It has broad application prospects in devices, alternative silver-based contact materials, electrical switch contact bridges, and welding torch nozzles.

The Glidcop series of Cu-Al ₂ O ₃ copper-based composite materials developed by SCM in the United States has a softening temperature of 900°C, an electrical conductivity of 90-92% IACS, and a tensile strength of 540 MPa, and has been mass-produced. However, its high-temperature performance, especially high-temperature short-term tensile performance is low, and cannot meet the high-temperature load-bearing performance requirements.

At present, the traditional manufacturing technology of dispersed copper mostly adopts the powder metallurgy method. At the beginning, the Al ₂ O ₃ particles are mixed evenly, and then pressed and formed and then sintered to form a sintered body. The production of Al ₂ O ₃ dispersion-strengthened copper by powder metallurgy is mature, and the performance of the composite material produced is good, but the production process is complicated, the cost is high, the production efficiency is low, and the interface of the composite material is easily polluted. The improved process is the most widely used powder internal oxidation powder metallurgy method, and its common technology flow is: alloy smelting → powder making → internal oxidation → reduction → pressing → sintering → thermal processing → cold processing, this manufacturing process is through internal oxidation in situ The generated nano-scale Al ₂ O ₃ particles are fine and evenly distributed in the matrix, and have high thermodynamic stability, but their high temperature performance is not good, and the process is complicated, which makes it difficult to control the quality of the material and the cost is very high, which greatly limits its application. Improving the high-temperature properties of Al ₂ O ₃ dispersion-strengthened copper composites, especially the high-temperature tensile properties is an urgent problem to be solved.

Contents of the invention

The purpose of the present invention is to provide an aluminum oxide particle dispersion strengthened copper composite material.

Another object of the present invention is to provide a method for preparing aluminum oxide particle dispersion strengthened copper composite material.

In order to achieve the above objectives, the technical solution adopted in the present invention is: a copper composite material reinforced by alumina particles, the chemical composition of which is: α-Al ₂ O ₃ with a weight percentage of 0.05-1.5%, and The content is 0.38-0.94% of γ-Al ₂ O ₃ , and the balance is copper.

A preparation method of aluminum oxide particle dispersion strengthened copper composite material, comprising the following steps:

(1) Ingredients

Take the raw materials α-Al ₂ O ₃ powder, Cu ₂ O and Cu-Al alloy powder; carry out batching according to the following weight ratio: the weight percentage of α-Al ₂ O ₃ powder is 0.05-1.5%, _the The weight percentage is 1.90-4.75%, and the balance is Cu-Al alloy powder; then the raw materials are fully mixed;

(2) Deformation sintering internal oxidation under vacuum or protective atmosphere

Put the raw material prepared in step (1) into a graphite mold, then put it into a high-temperature sintering furnace for sintering internal oxidation, and carry out plastic deformation at the same time. The sintering furnace atmosphere is vacuum or inert gas or ammonia decomposition gas, and the sintering internal oxidation temperature is 950°C, the holding time is 2-4 hours, the deformation pressure is 30-100MPa, and the pressure-holding time is 1-2 hours, and the sintered body is obtained, and the diameter of the sintered body is 30-100mm;

(3) hot extrusion

Heating the sintered body to 900-1000°C, and then performing hot extrusion with an extrusion ratio ≥ 10, and air cooling to room temperature after hot extrusion to obtain a hot extruded rod;

(4) cold deformation forming

The hot extruded bar is cold-drawn on a combined drawing machine, and the cold-drawing deformation is controlled at more than 80%, so that the aluminum oxide particle dispersion-strengthened copper composite material is obtained.

Preferably, the Cu-Al alloy powder is Cu-Al alloy powder produced by water mist method, the weight percentage of aluminum in the Cu-Al alloy powder is 0.20-0.50%, and the Cu-Al alloy powder The particle size is 37.0-106.0 microns.

The particle size of the α-Al ₂ O ₃ powder is 0.5-5.0 microns, and the purity of the α-Al ₂ O ₃ powder is: the weight percentage of α-Al ₂ O ₃ is ≥99.5%.

The particle size of the Cu ₂ O is 37.0-106.0 microns, and the purity of the Cu ₂ O is: the weight percentage of Cu ₂ O is ≥99.5%.

The aluminum oxide particle dispersion strengthened copper composite material provided by the present invention comprises Cu matrix and Al ₂ O ₃ reinforced particles, raw material Cu-Al alloy powder, α-Al ₂ O ₃ powder and oxidant Cu ₂ O powder are mixed, vacuum or protective atmosphere The multi-hybrid aluminum oxide particle-reinforced dispersion-strengthened copper composite material provided by the invention is prepared by internal oxidation through sintering under deformation. The role of the raw material α-Al ₂ O ₃ powder is mainly to prevent grain boundary sliding under high-temperature loading, and at the same time it has an Orowan strengthening effect; the role of the oxidant Cu ₂ O is to decompose at high temperature, providing active [O], and forming with solid solution Al In-situ chemical reaction, the raw material micron-sized α-Al ₂ O ₃ particles and the Al in the raw material Cu-Al alloy powder are oxidized by Cu ₂ O oxidant to generate nano-sized γ-Al ₂ O ₃ in situ, and the different structures formed and different The size of _Al2O3 is uniformly distributed on the copper matrix, which has a dispersion strengthening _effect .

The aluminum oxide particle dispersion-strengthened copper composite material provided by the present invention is prepared by the multi-hybrid Al ₂ O ₃ preparation technology. The so-called multi-hybrid includes three aspects of the source, structure and size of Al ₂ O ₃ . There are two sources of Al ₂ O ₃ in the aluminum oxide particle dispersion-strengthened copper composite material provided by the present invention. One is the raw material micron-sized corundum structure α-Al ₂ O ₃ , which pins the grain boundaries of the copper matrix and hinders the movement of dislocations. At the same time, it hinders the high-temperature sliding of grain boundaries to improve the high-temperature strength of aluminum oxide particle dispersion-strengthened copper composites; the other is the nano-scale face-centered cubic structure γ-Al ₂ O ₃ pinning subgrains generated by internal oxidation of Cu-Al alloys improve the recrystallization resistance of the deformed matrix, and improve _the high-temperature softening resistance of the aluminum _oxide particle dispersion-strengthened copper composite material. The electrical conductivity is significantly improved.

The performance index of the aluminum oxide particle dispersion strengthened copper composite material prepared by the preparation method provided by the invention is: tensile strength 500-610MPa, electrical conductivity 80-90% IACS, 600°C short-term tensile strength ≥ 150MPa.

The preparation method of the aluminum oxide particle dispersion-strengthened copper composite material provided by the invention has the advantages of short internal oxidation time, low cost and high efficiency, and the prepared alumina particle dispersion-strengthened copper composite material has high strength, high conductivity, high resistance Softening temperature and high temperature strength can meet the requirements of microelectronics industry and electronic information industry for high-conductivity, high-strength and high-temperature resistant copper alloys, and can be used for resistance welding electrodes, high-strength power lines, computer lead frames, continuous casting machine crystallizers, and silver substitutes Base contact materials, electrical switch contact bridges, welding torch nozzles and other fields are widely used in the machinery industry, national defense industry and electronic information industry.

Detailed ways

Example 1

The chemical composition of the aluminum oxide particle dispersion-strengthened copper composite material provided in this example is as follows: 0.05% by weight of α-Al ₂ O ₃ , 0.38% by weight of γ-Al ₂ O ₃ , and the remainder amount of copper.

The preparation method of the aluminum oxide particle dispersion strengthened copper composite material provided in this embodiment includes the following steps:

(1) Ingredients

Take the following raw materials: Cu-Al alloy powder produced by water mist method, _its aluminum content is 0.20wt%, particle size 37.0-106.0 microns; α- _Al2O3 powder, particle size 0.5-5.0 microns, purity ≥ 99.5wt%; oxidizing agent Cu ₂ O powder, particle size 37.0-106.0 microns, purity ≥ 99.5wt%;

Dosing according to the following weight ratio: the weight percentage of α-Al ₂ O ₃ powder is 0.05%, the weight percentage of Cu ₂ O is 1.90%, and the balance is Cu-Al alloy powder;

Then use a V-shaped mixer to fully mix the raw materials for 3 hours;

(2) Vacuum deformation sintering internal oxidation

Put the raw material powder mixed in step (1) into a graphite mold, and then put it into a vacuum high-temperature sintering furnace for sintering oxidation and plastic deformation at the same time. The sintering oxidation temperature is 950 ° C, the holding time is 4 hours, and the deformation pressure 35MPa, holding time for 1 hour. At this stage, the internal oxidation of solid solution Al and the densification of the powder mixture are simultaneously completed to obtain a sintered body with a diameter of 50mm;

(3) hot extrusion

The sintered body was heated to 1000°C, and hot-extruded on a press with an extrusion ratio of 10 to obtain a rod with a diameter of 15.8 mm, and then air-cooled to room temperature;

(4) cold deformation forming

The hot-extruded rod with a diameter of 15.8mm is cold-drawn for multiple passes on a LLB-type 10-ton combined drawing machine, and the cold-drawn diameter is 7.0mm, and the cold-drawing deformation is 80%, and the aluminum oxide particles are obtained. Dispersion strengthened copper composites.

The performance indexes of the aluminum oxide particle dispersion strengthened copper composite material prepared by the invention are: tensile strength 550MPa, electrical conductivity 89% IACS, 600°C short-time tensile strength 170MPa.

Example 2

The chemical composition of the aluminum oxide particle dispersion-strengthened copper composite material provided in this example is: 0.75% by weight of α-Al ₂ O ₃ , 0.66% by weight of γ-Al ₂ O ₃ , and the rest amount of copper.

The preparation method of the aluminum oxide particle dispersion strengthened copper composite material provided in this embodiment includes the following steps:

(1) Ingredients

Take the following raw materials: Cu-Al alloy powder produced by water mist method, _its aluminum content is 0.35wt%, particle size 37.0-106.0 microns; α- _Al2O3 powder, particle size 0.5-5.0 microns, purity ≥ 99.5wt%; oxidizing agent Cu ₂ O powder, particle size 37.0-106.0 microns, purity ≥ 99.5wt%;

Dosing according to the following weight ratio: the weight percentage of α-Al ₂ O ₃ powder is 0.75%, the weight percentage of Cu ₂ O is 3.30%, and the balance is Cu-Al alloy powder;

Then use a V-shaped mixer to fully mix the raw materials for 3 hours;

(2) Nitrogen protection deformation sintering internal oxidation

Put the raw material powder mixed in step (1) into a graphite mold, and then put it into an atmosphere-protected high-temperature sintering furnace for sintering internal oxidation and plastic deformation at the same time. The protective atmosphere is nitrogen, and the sintering internal oxidation temperature is 950°C. The time is 2 hours, the deformation pressure is 60MPa, and the holding time is 2 hours. At this stage, the internal oxidation of solid solution Al and the densification of the powder mixture are simultaneously completed to obtain a sintered body with a diameter of 80mm;

(3) hot extrusion

The sintered body was heated to 950° C., hot-extruded on a press with an extrusion ratio of 14 to obtain a rod with a diameter of 21.4 mm, and then air-cooled to room temperature;

(4) cold deformation forming

The hot-extruded rod with a diameter of 21.4mm was cold-drawn in multiple passes on a LLB-type 10-ton combined drawing machine until the diameter was 9.3mm, and the cold-drawing deformation was 81%, and alumina particles were obtained. Dispersion strengthened copper composites.

The performance indexes of the aluminum oxide particle dispersion strengthened copper composite material prepared by the invention are: tensile strength 590MPa, electrical conductivity 82% IACS, 600°C short-term tensile strength 190MPa.

Example 3

The chemical composition of the aluminum oxide particle dispersion-strengthened copper composite material provided in this example is: α-Al ₂ O ₃ with a weight percentage of 1.5%, γ-Al ₂ O ₃ with a weight percentage of 0.94%, and the remainder amount of copper.

The preparation method of the aluminum oxide particle dispersion strengthened copper composite material provided in this embodiment includes the following steps:

(1) Ingredients

Take the following raw materials: Cu-Al alloy powder produced by water mist method, _its aluminum content is 0.50wt%, particle size 37.0-106.0 microns; α- _Al2O3 powder, particle size 0.5-5.0 microns, purity ≥ 99.5wt%; oxidizing agent Cu ₂ O powder, particle size 37.0-106.0 microns, purity ≥ 99.5wt%;

Dosing according to the following weight ratio: the weight percentage of α-Al ₂ O ₃ powder is 1.5%, the weight percentage of Cu ₂ O is 4.75%, and the balance is Cu-Al alloy powder;

Then use a V-shaped mixer to fully mix the raw materials for 3 hours;

(2) Nitrogen protection deformation sintering internal oxidation

Put the raw material powder mixed in step (1) into a graphite mold, and then put it into an atmosphere-protected high-temperature sintering furnace for sintering internal oxidation and plastic deformation at the same time. The protective atmosphere is ammonia decomposition gas, and the sintering internal oxidation temperature is 950°C , the holding time is 4 hours, the deformation pressure is 35MPa, and the holding time is 2 hours. At this stage, the internal oxidation of solid solution Al and the densification of the powder mixture are simultaneously completed to obtain a sintered body with a diameter of 100mm;

(3) hot extrusion

The sintered body was heated to 1000°C, hot-extruded on a press with an extrusion ratio of 18 to obtain a rod with a diameter of 23.6 mm, and then air-cooled to room temperature;

(4) cold deformation forming

The hot-extruded rod with a diameter of 23.6mm was cold-drawn for multiple passes on a LLB-type 10-ton combined drawing machine until the diameter was 10.0mm, and the cold-drawing deformation was 82%, and alumina particles were obtained. Dispersion strengthened copper composites.

The performance indexes of the aluminum oxide particle dispersion strengthened copper composite material prepared by the invention are: tensile strength 610MPa, electrical conductivity 80% IACS, 600°C short-term tensile strength 200MPa.

Claims (5)

1. an aluminium oxide particles dispersion-strengthened carbon/carbon-copper composite material is characterized in that, the chemical ingredients of described aluminium oxide particles dispersion-strengthened carbon/carbon-copper composite material consists of: weight percentage is α-Al of 0.05～1.5% ₂O ₃, weight percentage is γ-Al of 0.38～0.94% ₂O ₃, the copper of surplus.

2. the preparation method of the described aluminium oxide particles dispersion-strengthened of claim 1 carbon/carbon-copper composite material is characterized in that, may further comprise the steps:

(1) batching

Get raw material α-Al ₂O ₃Powder, Cu ₂O and Cu-Al powdered alloy; Prepare burden according to following weight proportion: α-Al ₂O ₃The weight percentage of powder is 0.05～1.5%, Cu ₂The weight percentage of O is 1.90～4.75%, the Cu-Al powdered alloy of surplus; Afterwards raw material is fully mixed;

(2) oxidation in the deformation sintering under vacuum or the protective atmosphere

The raw material that step (1) is prepared places in the graphite jig, put into high temperature sintering furnace then and carry out the sintering oxidation, carry out viscous deformation simultaneously, sintering oven atmosphere is vacuum or rare gas element or decomposed ammonia body, and oxidizing temperature is 950 ℃ in the sintering, and soaking time is 2～4 hours, deformation pressure 30～100MPa, 1～2 hour dwell time made sintered compact, and the diameter of sintered compact is 30～100mm;

(3) hot extrusion

Described sintered compact is heated to 900～1000 ℃, carries out hot extrusion then, extrusion ratio 〉=10, air cooling obtains the hot extrusion bar to room temperature after the hot extrusion;

(4) cold deformation moulding

The hot extrusion bar is carried out cold drawing at the associating cold drawing bench, and the cold drawing deflection is controlled more than 80%, makes aluminium oxide particles dispersion-strengthened carbon/carbon-copper composite material.

3. the preparation method of aluminium oxide particles dispersion-strengthened carbon/carbon-copper composite material according to claim 2, it is characterized in that, the Cu-Al powdered alloy that described Cu-Al powdered alloy is produced for the water smoke method, the weight percentage of aluminium is 0.20～0.50% in the described Cu-Al powdered alloy, and the granularity of described Cu-Al powdered alloy is 37.0～106.0 microns.

4. the preparation method of aluminium oxide particles dispersion-strengthened carbon/carbon-copper composite material according to claim 2 is characterized in that, described α-Al ₂O ₃The granularity of powder is 0.5～5.0 micron, α-Al ₂O ₃The purity of powder is: α-Al ₂O ₃Weight percentage 〉=99.5%.

5. the preparation method of aluminium oxide particles dispersion-strengthened carbon/carbon-copper composite material according to claim 2 is characterized in that, described Cu ₂The granularity of O is 37.0～106.0 microns, described Cu ₂The purity of O is: Cu ₂The weight percentage of O 〉=99.5%.