CN110508816B - Preparation method of contact material for high-voltage direct-current relay - Google Patents
Preparation method of contact material for high-voltage direct-current relay Download PDFInfo
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Abstract
The invention discloses a preparation method of a contact material for a high-voltage direct-current relay, and belongs to the technical field of powder metallurgy material preparation. The method comprises the following steps of (1) performing two-time pressing and two-time sintering, wherein the first pressing is performed to form a blank, and after the initial sintering, the material stress is removed, so that the deformation strength is reduced; the secondary pressing aims at shaping to achieve the size of a final product and reduce the subsequent machining process, the secondary re-sintering can improve the mechanical strength and the toughness of the material and is beneficial to the service life of the material, and the product requires the mechanical life to reach millions of times, so that the secondary sintering is needed to improve the strength of the material; the invention relates to a newly developed preparation method of a contact material for a high-voltage direct-current relay, which is a contact material for the high-voltage direct-current relay with simple process, low cost and high performance, has high cost performance while meeting the use performance, can replace the existing pure copper contact, and greatly improves the reliability of the high-voltage direct-current relay.
Description
Technical Field
The invention belongs to the technical field of powder metallurgy material preparation, and particularly relates to a preparation method of a contact material for a high-voltage direct-current relay.
Background
With the popularization of new energy automobile strategy in China, the market holding amount of new energy automobiles is rapidly increased, the new energy automobiles generally adopt high-voltage battery packs to provide power drive for electric vehicles, in order to ensure the normal on-off of an electrical system, a high-voltage direct-current relay is required to be arranged between a battery system and a motor controller of the electric vehicles, the high-voltage direct-current relay plays a role in isolation after the system stops running, plays a role in connection when the system runs, and can safely separate an energy storage system from the vehicle electrical system and play a role in breaking a circuit when the vehicles are turned off or have faults, so the high-voltage direct-current relay is a key safety device of the new energy automobiles, and the electric vehicles cannot be started, run and stop if the high-voltage direct-current relay is not arranged. Such high working platform voltage requires high voltage direct current relay products to have the characteristics of good high voltage resistance, impact resistance and breaking capacity.
The contact is used as a core component of the high-voltage direct-current relay and needs to have the characteristics of high voltage resistance, strong load resistance, impact resistance, strong arc extinguishing capability, strong breaking capability and the like, and currently domestic high-voltage direct-current relay manufacturers generally purchase oxygen-free copper as the contact on the basis of cost pressure, wherein the oxygen-free copper has good electric conduction and heat conduction performance, but the electric arc ablation resistance and the large current impact resistance are poor, and the adopted dispersion strengthened copper material with good performance has high cost and complex process and cannot meet the price requirement of the market; therefore, a low-cost and high-performance material is urgently needed to replace the existing oxygen-free copper, improve the service performance of the high-voltage direct-current relay and have high cost performance.
In the prior art, the research on the contact material of the high-voltage direct-current relay is few, and the contact material is mainly based on the continuation or optimization of the contact of the existing low-voltage relay. However, the high-voltage direct-current relay has higher performance and reliability requirements compared with the traditional relay, and new requirements are provided, while the existing silver-based contact and copper-tungsten contact solve part of problems, but can not completely meet the requirements of the high-voltage direct-current relay, such as poor arc ablation resistance and fusion welding resistance of the silver-based contact and high cost; the copper-tungsten contact has low load current resistance and breaking capacity, and the two materials are difficult to weld and are not suitable for batch production.
Disclosure of Invention
Aiming at the existing problems, the invention provides a preparation method of a contact material for a high-voltage direct-current relay.
The technical scheme of the invention is as follows: a preparation method of a contact material for a high-voltage direct-current relay is characterized by mainly comprising the following steps:
(1) preparing materials: weighing a pure aluminum block and an oxygen-free copper bar as raw materials, wherein the raw materials comprise 0.1-1% of aluminum and the balance of copper by weight percent, wherein the purity of the oxygen-free copper bar is 99.9%, and the purity of the pure aluminum block is 99.95%;
(2) smelting: loading the oxygen-free copper rod and the pure aluminum block in the proportion into vacuum atomization equipment, firstly vacuumizing to below 10pa, heating for smelting at the smelting temperature of 1200-1500 ℃, and carrying out vacuum gas atomization after the oxygen-free copper rod is completely molten to prepare copper-aluminum alloy powder;
(3) internal oxidation: filling the prepared copper-aluminum powder into a high-pressure reaction kettle, introducing oxygen with the purity of more than 99.9%, heating to 600-1000 ℃, fully oxidizing the copper-aluminum powder to generate copper oxide and aluminum oxide powder, and keeping the temperature for 2-4 h; vacuumizing to be less than 0.2pa, introducing hydrogen with the purity of more than 99.5 percent, reducing the copper oxide into pure copper, and dispersing the aluminum oxide particles in the copper powder to form dispersion strengthened copper powder;
(4) powder mixing: adding one or more of WC, Ti and W high-melting-point alloys into the dispersion strengthening copper powder prepared by internal oxidation, wherein the addition amount is 0.1-20% of copper-aluminum powder, and then mixing by adopting a ball mill;
(5) and (3) pressing and forming: pressing the mixed alloy powder by a press to form a green body, wherein the pressing pressure is 500-1500MPa, and the pressure maintaining time is 1-10 s;
(6) and (3) sintering: sintering the pressed green body in a vacuum or gas-hydrogen sintering furnace, wherein the maximum sintering temperature is 800-;
(7) repressing: re-pressing the sintered compact at 1000-1600 MPa;
(8) re-burning: and (3) carrying out secondary sintering on the re-pressed compact, wherein the sintering temperature is 500-1000 ℃, and the heat preservation time is 1-4h, so that the high-performance contact material can be prepared.
Further, the inert gas is one or a mixed gas of argon gas and nitrogen gas, the atomization pressure is 3-8Mpa, and the alloy liquid forms micro liquid drops through the impact of the gas on the melted alloy liquid, and the micro liquid drops can not react with the alloy liquid, so that the purity of the alloy powder is ensured.
Further, when the vacuum atomization operation is performed in the step (2), the specific process is as follows: pouring molten alloy liquid into a drain ladle, spraying atomizing gas with the pressure of 0.6-8MPa in the process that the alloy liquid flows out through a drain nozzle at the speed of 8-15L/min, dispersing the alloy liquid into fine droplets, cooling and solidifying the fine droplets in the falling process to form aluminum alloy powder, and conveniently controlling the particle size of the small droplets of the alloy liquid by controlling the pressure of the atomizing gas and the flow rate of the alloy liquid.
Further, the granularity of the copper-aluminum alloy powder prepared in the step (2) is required to be below-100 meshes.
Further, in the ball milling process in the step (4), polyvinylpyrrolidone and a silane coupling agent are added into the ball mill, and under the action of the polyvinylpyrrolidone and the silane coupling agent, the particle size distribution of the mixed powder after ball milling is small, agglomeration is reduced, and segregation of the prepared alloy is avoided.
Further, in the step (4), the ball-milled mixed powder is subjected to plasma spheroidization, wherein the powder feeding rate is 60-150g/min, the plasma output power is 60-80KW, so that spherical mixed powder with uniform particle size is obtained, the ball-milled powder is treated by a plasma spheroidization technology, the uniformity of the particle size of the mixed powder is improved, and the alloy powder after the plasma spheroidization is subjected to compression molding, so that an alloy green compact with uniform tissue can be obtained, and segregation of alloy components is avoided.
Further, the ball-to-material ratio in the step (4) is 1:5-5:1, the ball milling time is 1-10h, if the ball-to-material ratio is more than 5:1, the impact friction between grinding bodies can be increased, the idle work is increased, the power consumption and the abrasion are increased, and the yield of the mixture is reduced; if the ball-material ratio is less than 1:5, the excessive material storage amount in the ball mill plays a buffering role, the excessive crushing phenomenon is increased, and the grinding efficiency is also reduced.
Further, the blank sintering in the step (6) comprises the following specific processes: s1: preheating: putting the pressed and formed blank into a vacuum or gas-hydrogen sintering furnace, preheating at the temperature of 300-; s: gradient temperature rise sintering: and raising the temperature of the preheated blank to 800-1050 ℃ at the temperature rise rate of 30-55 ℃, and preserving the heat for 2-3h, so that the blank is prevented from cracking and non-uniform deformation caused by too fast change of the sintering temperature in a preheating and gradient temperature rise mode, and the preparation of the contact material is prevented from being influenced.
Furthermore, when the annealing mode in the step (5) is stress relief annealing, the specific operations are as follows: s1, preheating the annealing furnace at the heating rate of 55-60 ℃/h until the temperature is raised to 630-650 ℃, then placing the blank subjected to the forging hammer into the preheated annealing furnace, and preserving the heat for 2-3 h; s2: introducing nitrogen into the annealing furnace, then heating the annealing furnace at a temperature rise rate of 200-250 ℃/h until the temperature rises to 1080-1200 ℃, and preserving the heat for 3-6 h; s3: reducing the temperature of the annealing furnace to 980-.
The invention has the beneficial effects that:
(1) the invention relates to a newly developed preparation method of a contact material for a high-voltage direct-current relay, which is a contact material for the high-voltage direct-current relay with simple process, low cost and high performance, has high cost performance while meeting the use performance, can replace the existing pure copper contact, and greatly improves the reliability of the high-voltage direct-current relay.
(2) The invention mainly shows the advantages in the aspect of the final performance of the material by controlling the content of the aluminum, when the content of the Al is less than 0.1 percent, the product has no obvious performance advantage compared with pure copper, but when the content of the Al is more than 1 percent, the conductivity of the product is reduced too much by adding the Al, and the conduction of a relay is not facilitated.
(3) Because the dispersion strengthening copper powder has higher hardness and the spherical powder is not easy to form, the invention carries out twice pressing and twice sintering, wherein, the first pressing is firstly carried out to form a blank, the material stress is removed after the initial sintering, and the deformation strength is reduced; the secondary pressing aims at shaping to achieve the size of a final product and reduce the subsequent machining process, the secondary re-sintering can improve the mechanical strength and the toughness of the material and is beneficial to the service life of the material, and the product requires the mechanical life to reach millions of times, so that the secondary sintering is needed to improve the strength of the material.
(4) During sintering, the invention controls the sintering temperature in a preheating and gradient heating mode, and avoids the influence on the preparation of the contact material caused by the cracking and uneven deformation of the blank due to the rapid change of the sintering temperature.
(5) According to the invention, by adding high-melting-point alloy such as WC, Ti, W and the like into the dispersion-strengthened copper powder prepared by internal oxidation, the arc ablation resistance and fusion welding resistance of the material can be improved in a targeted manner according to the current of a high-voltage relay.
Drawings
FIG. 1 is a process flow diagram of the present invention;
FIG. 2 is a gold phase diagram of the contact material of the present invention;
fig. 3 is a product drawing of the contact material of the present invention.
Detailed Description
The technical solution of the present invention is further described in detail with reference to the following examples, but the scope of the present invention is not limited thereto.
Example 1
The method for preparing the contact material for the high-voltage direct-current relay by using the method mainly comprises the following steps of:
(1) preparing materials: weighing a pure aluminum block and an oxygen-free copper bar as raw materials, wherein the raw materials comprise 0.1 percent of aluminum and 99.9 percent of copper in percentage by weight, the purity of the oxygen-free copper bar is 99.9 percent, and the purity of the pure aluminum block is 99.95 percent;
(2) smelting: loading the oxygen-free copper rod and the pure aluminum block in the proportion into vacuum atomization equipment, firstly vacuumizing to 10pa, heating to smelt at 1200 ℃, and carrying out vacuum atomization after the oxygen-free copper rod is completely smelted to prepare copper-aluminum alloy powder with the particle size of-100 meshes;
(3) internal oxidation: filling the prepared copper-aluminum powder into a high-pressure reaction kettle, introducing oxygen with the purity of 99.9%, heating to 600 ℃, fully oxidizing the copper-aluminum powder to generate copper oxide and aluminum oxide powder, and keeping the temperature for 2 hours; vacuumizing to 0.2pa, introducing hydrogen with the purity of 99.5%, reducing the copper oxide into pure copper, and dispersing aluminum oxide particles in the copper powder to form dispersion strengthened copper powder;
(4) powder mixing: adding WC into the dispersion strengthening copper powder prepared by internal oxidation, wherein the addition amount of the WC is 0.1 percent of copper-aluminum powder, and then mixing by adopting a ball mill, wherein the ball-material ratio is 1:5, the ball milling time is 1h, if the ball-material ratio is less than 1:5, the excessive material storage amount in the ball mill plays a buffering role, the over-crushing phenomenon is increased, and the grinding efficiency is also reduced;
(5) and (3) pressing and forming: pressing the mixed alloy powder by a press to form a green body, wherein the pressing pressure is 500Mpa, and the pressure maintaining time is 1 s;
(6) and (3) sintering: sintering the pressed green body in a vacuum or gas-hydrogen sintering furnace, wherein the maximum sintering temperature is 800 ℃, and keeping the temperature for 1 h;
(7) repressing: re-pressing the sintered compact at 1000 MPa;
(8) re-burning: and (3) sintering the re-pressed compact again for the second time, wherein the sintering temperature is 500 ℃, and the heat preservation time is 1h, so that the high-performance contact material can be prepared.
Example 2
The method for preparing the contact material for the high-voltage direct-current relay by using the method mainly comprises the following steps of:
(1) preparing materials: weighing a pure aluminum block and an oxygen-free copper bar as raw materials, wherein the raw materials comprise 0.5 percent of aluminum and 99.5 percent of copper in percentage by weight, the purity of the oxygen-free copper bar is 99.9 percent, and the purity of the pure aluminum block is 99.95 percent;
(2) smelting: loading the oxygen-free copper rod and the pure aluminum block in the proportion into vacuum atomization equipment, firstly vacuumizing to 9pa, heating to smelt at 1400 ℃, and carrying out vacuum atomization after the oxygen-free copper rod is completely smelted to prepare copper-aluminum alloy powder with the particle size of-100 meshes;
(3) internal oxidation: filling the prepared copper-aluminum powder into a high-pressure reaction kettle, introducing oxygen with the purity of 99.9%, heating to 800 ℃, fully oxidizing the copper-aluminum powder to generate copper oxide and aluminum oxide powder, and keeping the temperature for 3 hours; vacuumizing to 0.1pa, introducing hydrogen with the purity of 99.5%, reducing the copper oxide into pure copper, and dispersing aluminum oxide particles in the copper powder to form dispersion strengthened copper powder;
(4) powder mixing: adding WC and Ti into the dispersion strengthening copper powder prepared by internal oxidation, wherein the addition amount is 11% of copper-aluminum powder, and then mixing by adopting a ball mill, wherein the ball-material ratio is 1:3, and the ball milling time is 5 hours;
(5) and (3) pressing and forming: pressing the mixed alloy powder by a press to form a green body, wherein the pressing pressure is 800Mpa, and the pressure maintaining time is 5 s;
(6) and (3) sintering: sintering the pressed green body in a vacuum or gas-hydrogen sintering furnace, wherein the maximum sintering temperature is 1000 ℃, and keeping the temperature for 2 hours;
(7) repressing: re-pressing the sintered compact at 1400 MPa;
(8) re-burning: and (3) carrying out secondary sintering on the re-pressed compact, wherein the sintering temperature is 800 ℃, and the heat preservation time is 2 hours, so that the high-performance contact material can be prepared.
Example 3
The method for preparing the contact material for the high-voltage direct-current relay by using the method mainly comprises the following steps of:
(1) preparing materials: weighing a pure aluminum block and an oxygen-free copper bar as raw materials, wherein the raw materials comprise 1% of aluminum and 99% of copper in percentage by weight, the purity of the oxygen-free copper bar is 99.9%, and the purity of the pure aluminum block is 99.95%;
(2) smelting: loading the oxygen-free copper rod and the pure aluminum block in the proportion into vacuum atomization equipment, firstly vacuumizing to 8pa, heating to smelt at 1500 ℃, and carrying out vacuum atomization after the oxygen-free copper rod is completely smelted to prepare copper-aluminum alloy powder with the particle size of-100 meshes;
(3) internal oxidation: filling the prepared copper-aluminum powder into a high-pressure reaction kettle, introducing oxygen with the purity of 99.9%, heating to 1000 ℃, fully oxidizing the copper-aluminum powder to generate copper oxide and aluminum oxide powder, and keeping the temperature for 4 hours; vacuumizing to 0.2pa, introducing hydrogen with the purity of 99.5%, reducing the copper oxide into pure copper, and dispersing aluminum oxide particles in the copper powder to form dispersion strengthened copper powder;
(4) powder mixing: adding one or more of WC, Ti and W high-melting-point alloys into the dispersion strengthening copper powder prepared by internal oxidation, wherein the addition amount is 20 percent of copper-aluminum powder, and then mixing by adopting a ball mill, wherein the ball-material ratio is 5:1, and the ball milling time is 10 hours;
(5) and (3) pressing and forming: pressing the mixed alloy powder by a press to form a green body, wherein the pressing pressure is 1500Mpa, and the pressure maintaining time is 10 s;
(6) and (3) sintering: sintering the pressed green body in a vacuum or gas-hydrogen sintering furnace, wherein the maximum sintering temperature is 1100 ℃, and preserving heat for 4 hours;
(7) repressing: re-pressing the sintered compact at 1600 MPa;
(8) re-burning: and (3) carrying out secondary sintering on the re-pressed compact, wherein the sintering temperature is 1000 ℃, and the heat preservation time is 4 hours, so that the high-performance contact material can be prepared.
Example 4
This embodiment is substantially the same as embodiment 2 except that:
when the vacuum gas atomization operation is carried out in the step (2), the specific process is as follows: the molten alloy liquid is poured into a drain ladle, the molten alloy liquid is sprayed by using atomizing gas with the pressure of 4MPa in the process of flowing out through a drain nozzle at the speed of 12L/min, the alloy liquid is dispersed into fine droplets, aluminum alloy powder is formed after cooling and solidification in the process of falling, the particle size of the small droplets of the alloy liquid is conveniently controlled by controlling the pressure of the atomizing gas and the flow rate of the alloy liquid, wherein the inert gas is argon and nitrogen, the atomizing pressure is 5MPa, the molten alloy liquid forms micro droplets by the impact of the gas on the molten alloy liquid, and the micro droplets can not react with the alloy liquid, so that the purity of the alloy powder is ensured.
Example 5
This embodiment is basically different from embodiment 4 in that:
and (4) in the ball milling process in the step (4), adding polyvinylpyrrolidone and a silane coupling agent into the ball mill, under the action of the polyvinylpyrrolidone and the silane coupling agent, enabling the particle size distribution of the mixed powder after ball milling to be small, reducing agglomeration, avoiding segregation of the prepared alloy, carrying out plasma spheroidization on the mixed powder after ball milling, wherein the powder feeding rate is 120g/min, the plasma output power is 70KW, obtaining spherical mixed powder with uniform particle size, processing the powder after ball milling through a plasma spheroidization technology, increasing the uniformity of the particle size of the mixed powder, and carrying out press forming on the alloy powder after plasma spheroidization to obtain an alloy green compact with uniform tissue and avoid deviation of alloy components.
Example 6
This embodiment is basically different from embodiment 5 in that:
the blank sintering in the step (6) comprises the following specific processes: s1: preheating: putting the pressed blank into a vacuum or gas-hydrogen sintering furnace, preheating at 400 ℃, and preserving heat for 1.5 hours; s: gradient temperature rise sintering: the temperature of the preheated blank is increased to 950 ℃ at the temperature rising rate of 45 ℃, the blank is kept warm for 2.2 hours, and the blank is prevented from cracking and non-uniform deformation caused by too fast change of the sintering temperature in a preheating and gradient temperature rising mode, so that the preparation of the contact material is prevented from being influenced.
Example 7
When the annealing mode in the step (5) is stress relief annealing, the specific operation is as follows: s1, preheating the annealing furnace at the heating rate of 60 ℃/h until the temperature rises to 640 ℃, then placing the blank subjected to forging hammer into the preheated annealing furnace, and preserving the heat for 2.5 h; s2: introducing nitrogen into the annealing furnace, then heating the annealing furnace at a high temperature at a heating rate of 230 ℃/h until the temperature is raised to 1100 ℃, and preserving the heat for 4 h; s3: the temperature of the annealing furnace is reduced to 990 ℃ at the cooling rate of 23 ℃/h, the temperature is maintained for 2.5h, then the temperature of the annealing furnace is reduced to 630 ℃ at the cooling rate of 75 ℃/h, the temperature is maintained for 5h, finally, the blank is naturally cooled to 190 ℃, then the blank is taken out and placed in the air until the temperature is reduced to the room temperature, and the blank is annealed by the annealing mode, so that the residual stress in the blank can be eliminated, and the blank is prevented from being deformed and cracked due to the residual stress.
Test examples
The relevant performance parameters of the contact material for the high-voltage direct-current relay prepared according to the embodiments 1 to 7 of the invention are shown in table 1:
table 1: table of relevant performance parameters of contact material
As can be seen from Table 1, when the weight percentage of Al is 0.13-0.17%, the electrical conductivity of the alloy is 85-88%, the hardness is 115-135 and the density is 8.60; when the weight percentage of Al is 0.17-0.25%, the conductivity of the alloy is 80-84, the hardness is 132-150 and the density is 8.51, so that the contact material for the high-voltage direct-current relay prepared by the method is higher than pure copper, is favorable for the conductivity of the relay, has high hardness and density, can improve the mechanical strength and the toughness of the material, and is favorable for the service life of the material, and the product requires the mechanical life to reach millions of times, so that the secondary sintering is needed to improve the strength of the material.
Claims (1)
1. A preparation method of a contact material for a high-voltage direct-current relay is characterized by mainly comprising the following steps:
(1) preparing materials: weighing a pure aluminum block and an oxygen-free copper bar as raw materials, wherein the raw materials comprise 0.1-1% of aluminum and the balance of copper by weight percent, wherein the purity of the oxygen-free copper bar is 99.9%, and the purity of the pure aluminum block is 99.95%;
(2) smelting: loading the oxygen-free copper rod and the pure aluminum block in the proportion into vacuum atomization equipment, firstly vacuumizing to below 10pa, heating for smelting at the smelting temperature of 1200-1500 ℃, and carrying out vacuum gas atomization after the oxygen-free copper rod is completely molten to prepare copper-aluminum alloy powder;
(3) internal oxidation: filling the prepared copper-aluminum powder into a high-pressure reaction kettle, introducing oxygen with the purity of more than 99.9%, heating to 600-1000 ℃, fully oxidizing the copper-aluminum powder to generate copper oxide and aluminum oxide powder, and keeping the temperature for 2-4 h; vacuumizing to below 0.2pa, introducing hydrogen with the purity of more than 99.5%, reducing the copper oxide into pure copper, and dispersing the aluminum oxide particles in the copper powder to form dispersion-strengthened copper powder;
(4) powder mixing: adding one or more of WC, Ti and W high-melting-point alloys into the dispersion strengthening copper powder prepared by internal oxidation, wherein the addition amount is 0.1-20% of copper-aluminum powder, and then mixing by adopting a ball mill;
(5) and (3) pressing and forming: pressing the mixed alloy powder by a press to form a green body, wherein the pressing pressure is 500-1500MPa, and the pressure maintaining time is 1-10 s;
(6) and (3) sintering: sintering the pressed green body in a vacuum or gas-hydrogen sintering furnace, wherein the maximum sintering temperature is 800-;
(7) repressing: re-pressing the sintered compact at 1000-1600 MPa;
(8) re-burning: carrying out secondary sintering on the re-pressed compact, wherein the sintering temperature is 500-1000 ℃, and the heat preservation time is 1-4h, so as to prepare the high-performance contact material;
when the vacuum gas atomization operation is carried out in the step (2), the specific process is as follows: pouring molten alloy liquid into a drain ladle, spraying atomized gas with the pressure of 0.6-8MPa in the process that the alloy liquid flows out through a drain nozzle at the speed of 8-15L/min, dispersing the alloy liquid into fine liquid drops, and cooling and solidifying the fine liquid drops in the falling process to form copper-aluminum alloy powder;
the granularity requirement of the copper-aluminum alloy powder prepared in the step (2) is below-100 meshes;
the blank sintering in the step (6) comprises the following specific steps: s1: preheating: putting the blank formed by pressing into a vacuum or gas-hydrogen sintering furnace, preheating at the temperature of 300-500 ℃, and preserving heat for 1-2 h; s2: gradient temperature rise sintering: raising the temperature of the preheated blank to 800-;
when the vacuum gas atomization operation is carried out in the step (2), the atomization gas is inert gas, the inert gas is one or a mixture of argon and nitrogen, and the atomization pressure is 3-8 Mpa;
in the ball milling process in the step (4), polyvinylpyrrolidone and a silane coupling agent are added into the ball mill;
plasma spheroidizing is carried out on the mixed powder subjected to ball milling in the step (4), wherein the powder feeding speed is 60-150g/min, the plasma output power is 60-80KW, and spherical mixed powder with uniform particle size is obtained;
in the step (4), the ball-material ratio is 1:5-5:1, and the ball-milling time is 1-10 h.
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| DE3025042A1 (en) * | 1980-01-11 | 1981-07-16 | Sprecher & Schuh AG, 5001 Aarau, Aargau | ELECTRICALLY INSULATING PLASTIC PART FOR AN ELECTRICAL SWITCHGEAR, ESPECIALLY FOR USE AS A BLOW NOZZLE OF A PRESSURE GAS SWITCH |
| CN1936042A (en) * | 2006-10-20 | 2007-03-28 | 西安理工大学 | Method for preparing alumina dispersion-strenghtened copper-base composite material |
| CN104561638A (en) * | 2015-01-04 | 2015-04-29 | 河南科技大学 | Preparation method for Al2O3 dispersion strengthened copper matrix composite material |
| CN105087981A (en) * | 2015-07-31 | 2015-11-25 | 陕西斯瑞工业有限责任公司 | Preparation method for novel welding-resistant ablation-resistant long-service-life copper-chromium contact material |
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| DE3025042A1 (en) * | 1980-01-11 | 1981-07-16 | Sprecher & Schuh AG, 5001 Aarau, Aargau | ELECTRICALLY INSULATING PLASTIC PART FOR AN ELECTRICAL SWITCHGEAR, ESPECIALLY FOR USE AS A BLOW NOZZLE OF A PRESSURE GAS SWITCH |
| CN1936042A (en) * | 2006-10-20 | 2007-03-28 | 西安理工大学 | Method for preparing alumina dispersion-strenghtened copper-base composite material |
| CN104561638A (en) * | 2015-01-04 | 2015-04-29 | 河南科技大学 | Preparation method for Al2O3 dispersion strengthened copper matrix composite material |
| CN105087981A (en) * | 2015-07-31 | 2015-11-25 | 陕西斯瑞工业有限责任公司 | Preparation method for novel welding-resistant ablation-resistant long-service-life copper-chromium contact material |
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