A method for preparing high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy

Abstract

The present invention relates to the technical field of copper-iron alloys, and discloses a method for preparing a high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy, comprising the following steps: S1, preparing copper-aluminum alloy powder by atomization, and then preparing dispersion-strengthened copper alloy powder by internal oxidation and reduction treatment; S2, preparing mechanical alloying composite powder by ball milling; S3, pressing and forming the prepared powder; S4, sintering and densifying the pressed powder; and S5, finally performing deformation heat treatment. The purpose of the present invention is to provide a high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy with uniform and fine iron phase distribution, fine grains, excellent high-temperature performance, and good processing performance, so as to solve the problems of component segregation, coarse grains, poor high-temperature performance and processing performance of copper-iron alloy prepared by traditional melting and casting methods, and poor high-temperature performance caused by the growth and coarsening of initial iron particles and deformed iron fibers at high temperatures, and has important application prospects in the fields of electrical and rail transportation under high-temperature service conditions.

Description

Technical Field

[0001] The invention relates to the technical field of powder metallurgy and copper-iron alloys, and in particular to a method for preparing a high-strength, high-conductivity, and high-temperature-resistant powder metallurgy copper-iron alloy. Background Art

[0002] With the rapid development of modern electronic information, more and more electronic and electrical equipment are put into use. Copper-iron alloys have good prospects in large-scale industrial preparation and application due to their low cost, abundant raw materials, huge magnetoresistance effect and special physical properties. Copper-iron materials have both high conductivity and high magnetic permeability, which can simultaneously suppress or weaken electric and magnetic fields and control the radiation and propagation of electromagnetic waves from one area to another. Therefore, copper-iron alloy materials are ideal electromagnetic shielding functional materials.

[0003] The main methods for preparing copper-iron alloys are powder metallurgy and traditional smelting. In the traditional smelting method, due to the different material properties of copper and iron, the two are prone to two-phase separation during the smelting preparation process, which can easily lead to low strength and conductivity of the produced material. In the powder metallurgy method, powder raw material processing is achieved by mixing powders of different materials during powder preparation. However, the degree of mixing of the powder after such treatment is low, and the strength, conductivity and high temperature resistance of the prepared alloy will be affected.

[0004] For example, a Chinese patent (publication number: CN114293045B) discloses a method for preparing a high-strength and high-conductivity powder metallurgy copper-iron alloy. The process steps include mixing atomized copper-iron alloy powder and copper-phosphorus alloy powder, and preparing plate, strip and rod-shaped copper-iron alloy by cold isostatic pressing, vacuum sintering and subsequent deformation processing. The purpose of the invention is to provide a method for preparing a high-strength and high-conductivity powder metallurgy copper-iron alloy with low oxygen content, fine grains, fine and uniformly distributed iron phase and good processing performance, so as to solve the problems of component segregation, coarse grains and poor processing performance of copper-iron alloy prepared by traditional smelting method, as well as high oxygen content, high sintering temperature and difficulty in precipitation of solid-solution iron phase in traditional powder metallurgy copper-iron alloy. The invention technology is easy to realize large-scale industrial production and has important application prospects in 5G communications, 3C electronic products and rail transportation.

[0005] This patent prepares copper-iron alloy by combining existing powder metallurgy technology with deformation processing. Although it solves the problems of traditional molten casting component segregation and coarse grains, the nano and submicron iron particles precipitated during high-temperature sintering will grow to the micron level, which will reduce the fiber strengthening effect produced by fine iron; in addition, the softening temperature of the alloy is low, and the iron fibers will grow and coarsen at high temperatures, reducing the high-temperature strength. It does not solve the problem of poor high-temperature performance of high-iron content copper-iron alloys. Therefore, a preparation method of high-strength, high-conductivity and high-temperature resistant powder metallurgy copper-iron alloy is proposed to solve the above-mentioned problems. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the shortcomings of the prior art, the present invention provides a method for preparing a high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy, which has the advantages of high strength, high conductivity, and high temperature resistance, and solves the problem of low softening temperature caused by the growth of initial fine iron particles and coarsening of deformed iron fibers under high temperature conditions.

[0008] (II) Technical solution

[0009] In order to achieve the above-mentioned high-strength, high-conductivity and high-temperature resistance purpose, the present invention provides the following technical solution: a method for preparing a high-strength, high-conductivity and high-temperature resistant powder metallurgy copper-iron alloy, comprising the following steps:

[0010] S1 Preparation of dispersion-strengthened copper alloy powder: Copper-aluminum alloy powder is prepared by atomization method, electrolytic copper (purity>99.99%) and high-purity aluminum (purity>99.99%) are weighed in proportion, and copper-aluminum alloy powder is prepared under high-pressure atomization medium after vacuum or non-vacuum smelting; the copper-aluminum alloy powder is then placed in a nitrogen-oxygen mixed atmosphere, the oxygen partial pressure is adjusted, and internal oxidation treatment is performed, and the completely internally oxidized powder is then reduced in a hydrogen atmosphere reduction furnace to obtain alumina dispersion-strengthened copper alloy powder;

[0011] S2 Mechanical alloying composite powder preparation: Alumina dispersion-strengthened copper alloy powder and high-purity iron powder (purity> 99.99%) are mixed according to the composition ratio and put into a ball mill for ball milling until the iron is completely dissolved into the dispersion-strengthened copper alloy powder to obtain copper, iron and alumina mechanical alloying composite powder;

[0012] S3: pressing and forming: putting the composite powder obtained in step S2 into an elastic colloid package, placing it in a cold isostatic press for pressing and forming to obtain a formed green body; or pressing and forming the composite powder obtained in step S2 by a steel die to obtain a formed green body;

[0013] S4 sintering and densification: placing the formed green body obtained in step S3 in a vacuum sintering furnace or an atmosphere protection sintering furnace for sintering to obtain an alumina dispersion strengthened copper-iron alloy sintered ingot;

[0014] S5 deformation heat treatment: the alumina dispersion strengthened copper-iron alloy sintered ingot obtained in step S4 is taken out from the sintering furnace, and then hot extruded and drawn to obtain rods or wires, and then aging heat treated under the protection of hydrogen atmosphere to obtain high-strength, high-conductivity and high-temperature resistant powder metallurgy copper-iron alloy rods or wires.

[0015] Furthermore, the copper-aluminum alloy powder in step S1 can be prepared by one or more of water atomization, gas atomization, and water-gas combined atomization processes, with an average particle size of 1-80 μm; the mass fraction of aluminum is 0.1-0.6%, and the rest is copper; the internal oxidation treatment temperature is 300-500 ° C, and the internal oxidation time is 1-5 h; the reduction treatment temperature is 300-600 ° C, and the reduction time is 1-4 h.

[0016] Furthermore, the mass fraction of the pure iron powder in step S2 is 0.05-20%, and the rest is dispersion-strengthened copper alloy powder. The ball milling time is 5-50 h, and the ball-to-material ratio is 3:1-10:1.

[0017] Furthermore, the pressure of the cold isostatic pressing in step S3 is 150-600 MPa, the pressure of the compression molding is 200-400 MPa, and the holding time is 15-150 s.

[0018] Furthermore, the atmosphere in the protective furnace in step S4 may be one or more of hydrogen, nitrogen, argon, methane, acetylene, and carbon monoxide, the sintering temperature is 950-1050°C, the holding time is 2-6 h, and the vacuum degree of the vacuum sintering furnace is 10 -1 -10 -3 Pa.

[0019] Furthermore, in the hot extrusion, hot rolling and heat treatment in step S5, the hot extrusion temperature is 800-1000°C, the hot rolling temperature is 850-1000°C, and the annealing heat treatment temperature is 300-600°C.

[0020] (III) Beneficial effects

[0021] Compared with the prior art, the present invention provides a method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy, which has the following beneficial effects:

[0022] 1. The preparation method of the high-strength, high-conductivity and high-temperature resistant powder metallurgy copper-iron alloy realizes the preparation of high-performance composite powder through the preparation of high-purity ultrafine copper-aluminum alloy powder, precise control of internal oxidation and reduction processes, and alloying of dispersion-strengthened copper powder and iron powder. The initial iron particle size of the prepared copper-iron alloy is controlled to be small, reaching the nanometer and submicron level, and the distribution is uniform without segregation, thereby improving the strength and conductivity of the alloy.

[0023] 2. The preparation method of the high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy introduces nano-alumina elements into the copper-iron alloy to improve the room temperature and high-temperature strength of the alloy. The densification and deformation heat treatment of the alloy powder are controlled through the control of the heat treatment process, thereby preparing a high-strength, high-conductivity, and high-temperature resistant copper-iron alloy that meets the service performance requirements of the alloy in a high-temperature environment.

[0024] 3. The preparation method of the high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy has a simple preparation process, a short process, high production efficiency, and low cost. It can realize continuous large-scale production and has important application prospects in the electrical and rail transportation fields that require high-temperature service conditions. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Example 1

[0027] A method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy comprises the following steps:

[0028] S1 uses a water atomization powder making process to prepare copper-aluminum alloy powder. Electrolytic copper (purity>99.99%) and high-purity aluminum (purity>99.99%) are weighed in proportion, the mass fraction of aluminum is 0.1 wt%, and the rest is copper. The average particle size is 5 μm. The copper-aluminum alloy powder is then placed in a nitrogen-oxygen mixed atmosphere, the oxygen partial pressure is adjusted, and the powder is internally oxidized at 400°C for 4 hours. It is then reduced with hydrogen at 500°C for 5 hours to obtain alumina dispersion-strengthened copper alloy powder.

[0029] S2 weighed alumina dispersion-strengthened copper alloy powder with an average particle size of 5 μm and high-purity iron powder with an average particle size of 10 μm, wherein the mass fraction of the high-purity iron powder was 5 wt%, and then put them into a vibration ball mill for ball milling, and the ball milling time was 12 h, and the ball-to-material ratio was 10:1. After the ball milling, a uniformly mixed copper, iron and alumina mechanical alloying composite powder was obtained;

[0030] S3: The mixed powder is put into a silica gel bag, the inner cavity of which is φ95×300 mm in size, and after packaging, it is put into a cold isostatic press for pressing. The cold isostatic pressing pressure is 250 MPa, and the holding time is 100 s. After pressing, a rod blank of φ88×281 mm is obtained.

[0031] S4 puts the green bar formed by cold isostatic pressing into a vacuum sintering furnace. A crucible of 1 kg pure titanium powder is placed in the furnace. After vacuuming, vacuum sintering is performed. The vacuum degree is 10 -1 Pa, sintering temperature is 1000 ℃, holding time is 4 h, and alloy sintered rod blank is obtained after sintering;

[0032] S5 hot extrudes the sintered rod blank at 950 °C. The rod diameter after extrusion is 15 mm. Then the surface oxide scale is removed and the wire is drawn to a diameter of 1 mm. Finally, it is annealed at 400 °C for 2 h to obtain a copper-iron alloy wire with an Fe content of 5 wt.% and a diameter of 1 mm. The wire has a tensile strength of 625 MPa, a conductivity of 68% IACS, and a softening temperature of 700 °C.

[0033] Example 1-1

[0034] The only difference from Example 1 is that the production parameter values ​​in the method for preparing the high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 300°C, the original treatment temperature in step S2 is 300°C, the cold isostatic pressing pressure in step S3 is 150 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -1 Pa, the annealing heat treatment temperature in step S5 is 300°C, and the other recipes and step parameters are the same.

[0035] Example 1-2

[0036] The difference from Example 1 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 500°C, the original treatment temperature in step S2 is 600°C, the cold isostatic pressing pressure in step S3 is 600 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -3 Pa, the annealing heat treatment temperature in step S5 is 600°C, and the other recipes and step parameters are the same.

[0037] Example 2

[0038] The only difference from Example 1 is that the raw material parameter ratios in the method for preparing a high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy are different: the Fe content is 10 wt.%, the Al content is 0.1 wt.%, and the average grain size is 1.9 μm. The remaining steps and production parameters are the same.

[0039] Finally, a copper-iron alloy wire with a diameter of 1 mm and a hardness of 235 HV was produced, with a tensile strength of 712 MPa, a conductivity of 62 %IACS, and a softening temperature of 750 °C.

[0040] Example 2-1

[0041] The difference from Example 2 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 300°C, the original treatment temperature in step S1 is 300°C, the cold isostatic pressing pressure in step S3 is 150 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -1 Pa, the annealing heat treatment temperature in step S5 is 300°C, and the other recipes and step parameters are the same.

[0042] Example 2-2

[0043] The difference from Example 2 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 500°C, the original treatment temperature in step S2 is 600°C, the cold isostatic pressing pressure in step S3 is 600 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -3 Pa, the annealing heat treatment temperature in step S5 is 600°C, and the other recipes and step parameters are the same.

[0044] Example 3

[0045] The only difference from Example 1 is that the raw material parameter ratios in the method for preparing a high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy are different: the Fe content is 10 wt.%, the Al content is 0.35 wt.%, and the average grain size is 1.3 μm. The remaining steps and production parameters are the same.

[0046] Finally, a copper-iron alloy wire sheet with a diameter of 1 mm and a hardness of 256 HV was produced, with a tensile strength of 782 MPa, a conductivity of 58% IACS, and a softening temperature of 800 °C.

[0047] Example 3-1

[0048] The difference from Example 3 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 300°C, the original treatment temperature in step S1 is 300°C, the cold isostatic pressing pressure in step S3 is 150 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -1 Pa, the annealing heat treatment temperature in step S5 is 300°C, and the other recipes and step parameters are the same.

[0049] Example 3-2

[0050] The only difference from Example 3 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 500°C, the original treatment temperature in step S2 is 600°C, the cold isostatic pressing pressure in step S3 is 600 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -3 Pa, the annealing heat treatment temperature in step S5 is 600°C, and the other recipes and step parameters are the same.

[0051] Example 4

[0052] The only difference from Example 1 is that the raw material parameter ratios in the method for preparing a high-strength, high-conductivity, and high-temperature resistant powder metallurgy copper-iron alloy are different: the Fe content is 20 wt.%, the Al content is 0.6 wt.%, and the average grain size is 0.8 μm. The remaining steps and production parameters are the same.

[0053] Finally, a copper-iron alloy wire sheet with a diameter of 1 mm and a hardness of 286 HV was produced, with a tensile strength of 885 MPa, a conductivity of 52 %IACS, and a softening temperature of 880 °C.

[0054] Example 4-1

[0055] The only difference from Example 4 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 300°C, the original treatment temperature in step S1 is 300°C, the cold isostatic pressing pressure in step S3 is 150 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -1 Pa, the annealing heat treatment temperature in step S5 is 300°C, and the other recipes and step parameters are the same.

[0056] Example 4-2

[0057] The only difference from Example 4 is that the production parameter values ​​in the method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy are different: the internal oxidation treatment temperature of the oxygen partial pressure in step S1 is 500°C, the original treatment temperature in step S2 is 600°C, the cold isostatic pressing pressure in step S3 is 600 MPa, and the vacuum degree of the vacuum sintering furnace in step S4 is 10 -3 Pa, the annealing heat treatment temperature in step S5 is 600°C, and the other recipes and step parameters are the same.

[0058] The alloy composition, hardness, tensile strength, conductivity and softening temperature in the embodiment are listed in Table 1:

[0059] Table 1 Composition, hardness, strength and conductivity of different copper-iron alloys

[0060]

[0061] From Table 1, we can know that:

[0062] 1. Under the same production parameters, that is, the internal oxidation temperature is 400 ℃, the original treatment temperature is 500 ℃, the static pressure is 250 MPa, and the vacuum degree is 10 -1 When the annealing temperature is 400 ℃, the Fe content is 5wt.%, the Al content is 0.10wt.%, and the average grain size is 2.5 μm, the steel alloy wire sheet with a specification of 1 mm wire produced has the following properties: hardness of 213 HV, tensile strength of 625 MPa, and electrical conductivity of 68% IACS.

[0063] When the Fe content is 10 wt.%, the Al content is 0.25 wt.%, and the average grain size is 1.9 μm, the steel alloy wire sheet with a specification of 1 mm wire produced has the following properties: hardness of 235 HV, tensile strength of 712 MPa, and electrical conductivity of 62% IACS.

[0064] When the Fe content is 10 wt.%, the Al content is 0.35 wt.%, and the average grain size is 1.3 μm, the steel alloy wire sheet with a specification of 1 mm plate produced has the following properties: hardness of 256 HV, tensile strength of 782 MPa, and electrical conductivity of 58% IACS.

[0065] When the Fe content is 20 wt.%, the Al content is 0.6 wt.%, and the average grain size is 0.8 μm, the steel alloy wire sheet with a specification of 1 mm produced has the following properties: hardness of 286 HV, tensile strength of 885 MPa, and electrical conductivity of 52% IACS.

[0066] 2. When the raw material parameters remain unchanged, the Fe content is 5 wt.%, the Al content is 0.10 wt.%, and the average grain size is 2.5 μm, the production parameters are changed, namely, the internal oxidation temperature is 400 °C, the original treatment temperature is 500 °C, the static pressure is 250 MPa, and the vacuum degree is 10 -1 When the annealing temperature is 400 °C and the annealing temperature is 400 °C, the steel alloy wire sheet with a specification of 1 mm wire is finally produced, and the copper-iron alloy wire sheet with a hardness of 213 HV, a tensile strength of 625 MPa, a conductivity of 68%IACS, and a softening temperature of 700 °C is produced.

[0067] When the raw material parameters remain unchanged, the Fe content is 10 wt.%, the Al content is 0.25 wt.%, and the average grain size is 1.9 μm, the production parameters are changed, namely, the internal oxidation temperature is 400 °C, the original treatment temperature is 500 °C, the static pressure is 250 MPa, and the vacuum degree is 10 -1 When the annealing temperature is 400 °C and the annealing temperature is 400 °C, the steel alloy wire sheet with a specification of 1 mm wire is finally produced, and the copper-iron alloy wire sheet with a hardness of 235 HV, a tensile strength of 712 MPa, a conductivity of 62%IACS, and a softening temperature of 750 °C is produced.

[0068] When the raw material parameters remain unchanged, the Fe content is 10 wt.%, the Al content is 0.35 wt.%, and the average grain size is 1.3 μm, the production parameters are changed, namely, the internal oxidation temperature is 400 °C, the original treatment temperature is 500 °C, the static pressure is 250 MPa, and the vacuum degree is 10 -1 When the annealing temperature is 400 °C and the annealing temperature is 400 °C, the steel alloy wire plate with a specification of 1 mm is finally produced, and the copper-iron alloy wire plate with a hardness of 256 HV, a tensile strength of 782 MPa, a conductivity of 58%IACS, and a softening temperature of 800 °C is produced.

[0069] When the raw material parameters remain unchanged, the Fe content is 20 wt.%, the Al content is 0.60 wt.%, and the average grain size is 0.8 μm, the production parameters are changed, namely, the internal oxidation temperature is 400 °C, the original treatment temperature is 500 °C, the static pressure is 250 MPa, and the vacuum degree is 10 -1 When the annealing temperature is 400 °C and the annealing temperature is 400 °C, the steel alloy wire plate with a specification of 1 mm is finally produced, and the copper-iron alloy wire plate with a hardness of 286 HV, a tensile strength of 885 MPa, a conductivity of 52%IACS, and a softening temperature of 880 °C is produced.

[0070] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy, characterized in that: The following steps are involved: S1 Preparation of dispersion-strengthened copper alloy powder: copper-aluminum alloy powder is prepared by atomization method, electrolytic copper and high-purity aluminum are weighed in proportion, and copper-aluminum alloy powder is prepared under high-pressure atomization medium after vacuum or non-vacuum smelting; the copper-aluminum alloy powder is then placed in a nitrogen-oxygen mixed atmosphere, the oxygen partial pressure is adjusted, and internal oxidation treatment is performed, and then the completely internally oxidized powder is reduced in a hydrogen atmosphere reduction furnace to obtain alumina dispersion-strengthened copper alloy powder; S2 Mechanical alloying composite powder preparation: Alumina dispersion-strengthened copper alloy powder and high-purity iron powder are mixed according to the composition ratio and put into a ball mill for ball milling until the iron is completely dissolved into the dispersion-strengthened copper alloy powder to obtain copper, iron and alumina mechanical alloying composite powder; S3: pressing and forming: putting the composite powder obtained in step S2 into an elastic colloid package, placing it in a cold isostatic press for pressing and forming to obtain a formed green body; or pressing and forming the composite powder obtained in step S2 by a steel die to obtain a formed green body; S4 sintering densification: placing the formed green body obtained in step S3 in a vacuum sintering furnace or an atmosphere protection sintering furnace for sintering to obtain an alumina dispersion strengthened copper-iron alloy sintered ingot, wherein the atmosphere protection sintering furnace in step S4 contains one or more of hydrogen, nitrogen, argon, methane, acetylene, and carbon monoxide, the sintering temperature is 950-1050°C, the holding time is 2-6 h, and the vacuum degree of the vacuum sintering furnace is 10 -1 -10 -3 Pa; S5 deformation heat treatment: the alumina dispersion strengthened copper-iron alloy sintered ingot obtained in step S4 is taken out from the sintering furnace, and then hot extruded and drawn to obtain rods or wires, and then annealed to obtain high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy rods or wires. The hot extrusion temperature in step S5 is 800-1000°C, and the annealing heat treatment temperature is 300-600°C.

2. The method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy according to claim 1, characterized in that: The copper-aluminum alloy powder in step S1 is prepared by one or more of water atomization, gas atomization, and water-gas combined atomization processes, with an average particle size of 1-80 μm; the mass fraction of aluminum is 0.1-0.6%, and the rest is copper; the internal oxidation treatment temperature is 300-500°C, and the internal oxidation time is 1-5 h; the reduction treatment temperature is 300-600°C, and the reduction time is 1-4 h.

3. The method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy according to claim 1, characterized in that: The mass fraction of the pure iron powder in step S2 is 0.05-20%, and the rest is dispersion-strengthened copper alloy powder. The ball milling time is 5-50 h, and the ball-to-material ratio is 3:1-10:

1.

4. The method for preparing a high-strength, high-conductivity, high-temperature resistant powder metallurgy copper-iron alloy according to claim 1, characterized in that: The pressure of the cold isostatic pressing in step S3 is 150-600 MPa, the pressure of the compression molding is 200-400 MPa, and the holding time is 15-150 s.

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