CN111636023B - Preparation method of copper-tungsten gradient material electrical contact - Google Patents
Preparation method of copper-tungsten gradient material electrical contact Download PDFInfo
- Publication number
- CN111636023B CN111636023B CN202010326243.XA CN202010326243A CN111636023B CN 111636023 B CN111636023 B CN 111636023B CN 202010326243 A CN202010326243 A CN 202010326243A CN 111636023 B CN111636023 B CN 111636023B
- Authority
- CN
- China
- Prior art keywords
- tungsten
- copper
- layer
- powder
- mixed powder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C27/00—Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
- C22C27/04—Alloys based on tungsten or molybdenum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/045—Alloys based on refractory metals
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/05—Mixtures of metal powder with non-metallic powder
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
- C23C4/06—Metallic material
- C23C4/08—Metallic material containing only metal elements
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
- C23C4/134—Plasma spraying
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/02—Contacts characterised by the material thereof
- H01H1/021—Composite material
- H01H1/025—Composite material having copper as the basic material
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H11/00—Apparatus or processes specially adapted for the manufacture of electric switches
- H01H11/04—Apparatus or processes specially adapted for the manufacture of electric switches of switch contacts
- H01H11/048—Apparatus or processes specially adapted for the manufacture of electric switches of switch contacts by powder-metallurgical processes
Abstract
The invention discloses a method for preparing an electrical contact made of copper-tungsten gradient material, belonging to the technical field of electrical contact preparation. The gradient copper-tungsten electrical contact material with gradient change is obtained by continuously changing the proportion of the copper material and the tungsten material, the high-tungsten part has high arc ablation resistance and fusion welding resistance, and the high-copper part has good electric conductivity and thermal conductivity; by adding rare earth oxide into each layer of mixed powder, the heat-conducting property of the contact material is improved, and the content of the added rare earth oxide is adjusted according to the change of the copper content in the mixed powder, so that the ratio of copper to tungsten in each layer of mixed powder of raw materials can be ensured, and the integral heat-conducting uniformity can be improved.
Description
Technical Field
The invention belongs to the technical field of electric contact preparation, and particularly relates to a preparation method of a copper-tungsten gradient material electric contact.
Background
The copper-tungsten alloy is a two-phase pseudo alloy consisting of two metals of tungsten and copper with greatly different physical properties, has excellent arc ablation resistance and fusion welding resistance, and has good electric conduction and thermal conduction, so that the copper-tungsten alloy is widely applied to various switch arc contacts and is the most widely applied electric contact material in various switches at present.
The single-component alloy prepared by the traditional copper-tungsten alloy electrical contact through an infiltration method mainly comprises the following preparation processes: the method comprises the steps of adding a forming agent into tungsten powder, performing compression molding, removing the forming agent, sintering the framework at a high temperature, and infiltrating copper, wherein the forming agent is required to be added for compression molding due to poor formability of the tungsten powder, then the forming agent is removed by heating in a furnace, the temperature of the forming agent is required to be slowly raised, the production efficiency is low, the infiltration process is to use the action of capillary force to wet and fill the porous tungsten framework with metal copper liquid with a lower melting point, the metal copper liquid flows along gaps of particles to fill the pores of the porous framework, the infiltration time is long, the traditional copper-tungsten material has single component, the electric arc ablation resistance and the electrical property of the material cannot be simultaneously improved, the production process is complex, the production.
With the gradual increase of the load of the high-voltage power transmission and transformation network, the requirements on the copper-tungsten electrical contact are higher and higher, and in addition, the improvement of the voltage grade and the rigor of the working conditions require that the electrical contact material has higher arc ablation resistance and higher heat conduction and electrical performance. The copper-tungsten functionally graded material has better arc ablation resistance and heat conduction performance, and the prepared copper-tungsten functionally graded material electric contact can improve the arc erosion resistance of the electric contact and prolong the service life of the electric contact, so the copper-tungsten functionally graded material electric contact has market prospect for preparing electric contact materials.
The existing uniform copper-tungsten electrical contact has poor high-voltage breaking capacity and short service life, so a method for preparing the copper-tungsten functionally gradient material electrical contact with high arc ablation resistance, high heat conductivity and prolonged service life is urgently needed.
Disclosure of Invention
Aiming at the problems of poor high-voltage breaking capacity and short service life of the conventional uniform copper-tungsten electrical contact, the invention provides a method for manufacturing a copper-tungsten functional gradient material electrical contact, which can improve the arc ablation resistance, the heat conduction performance and the service life of parts of the electrical contact.
The technical scheme of the invention is as follows: a preparation method of a copper-tungsten gradient material electrical contact mainly comprises the following steps:
step 1: the weight percentage is as follows: preparing 40-90% of tungsten powder and the balance of copper powder into mixed powder with different components, then pouring the mixed powder of each component into a planetary high-energy ball mill for ball milling to obtain mixed powder with different tungsten contents, and taking argon as protective gas, wherein the ball-material ratio is 20: 1-50: 1, the rotating speed is 600-1000 r/min, and the ball milling time is 8-24 h;
step 2: dividing the tungsten powder and the copper powder subjected to high-energy ball milling into a plurality of layers according to the sequence that the tungsten content is reduced from bottom to top, pouring the layers into a graphite mold layer by layer, putting the graphite mold into a discharge plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 30-50MPa, heating to 1200-1300 ℃, preserving heat for 3-5min, and cooling along with the furnace to obtain a sintered body;
and step 3: and carrying out surface machining on the sintered body to obtain the copper-tungsten gradient material.
Furthermore, in the step 1, the particle size of the tungsten powder is 2-8um, the copper powder is electrolytic copper powder of-200 meshes, the influence of the particle size of the powder on the performance of the tungsten-copper electrical contact material is obvious, and the electrical contact made of thinner or thicker powder has poor arc burning resistance and cannot meet the use requirement.
Further, in the step 2, before the ball-milled powder is poured into the graphite mold, the graphite mold is cleaned, and the specific treatment process comprises: firstly, placing a graphite mold into a cleaning tank added with hydrofluoric acid for soaking for 3-5h, then placing the soaked graphite mold into an ultrasonic cleaning tank, cleaning for 10-20min, then taking out the cleaned graphite mold, washing the graphite mold for 25-35min by using a washing water gun, finally placing the cleaned graphite mold into a drying box for drying, and cooling to normal temperature, soaking the graphite mold through the hydrofluoric acid, removing a natural oxidation film on the surface of the graphite mold, and simultaneously cleaning by combining ultrasonic waves, so that metal and organic pollutants embedded in an oxidation layer can be removed, the purity of the prepared electrical contact is prevented from being influenced by the pollutants, and the performance of the electrical contact is reduced.
Further, in the step (2), the tungsten powder and the copper powder after the high-energy ball milling are divided into three layers according to the sequence that the tungsten content is reduced from bottom to top, the tungsten content in each layer of mixed powder is 80%, 70% and 60%, the copper-tungsten gradient electrical contact material with gradient change is obtained by continuously changing the proportion of the two materials of copper and tungsten, the high-tungsten part has high arc ablation resistance and fusion welding resistance, and the high-copper part has good electric conduction and thermal conduction.
Further, the three-layer mixed powder in the step (2) can be subjected to layer-by-layer sintering treatment, and the specific sintering process is as follows: firstly, pouring a first layer of mixed powder into a graphite mold, putting the graphite mold into a plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 45-50MPa, heating to 1200-1300 ℃, preserving heat for 3-5min, cooling along with the furnace to obtain a first sintered body, spraying a second layer of mixed powder onto the surface of the preheated sintered body by using a plasma spraying technology to obtain a second sintered body, repeatedly spraying a third layer of mixed powder onto the surface of the second sintered body by using the plasma spraying technology to obtain a third sintered body, finally cooling to room temperature, preparing a first layer with the highest tungsten content as a substrate template, respectively spraying the powder with different tungsten contents by using the plasma spraying technology, avoiding the simultaneous sintering of four layers of powder with different tungsten contents to cause mutual melting among the powder of each layer and influence on the copper-tungsten ratio of each layer, the arc erosion resistance of the high tungsten layer and the fusion welding resistance of the high copper layer are reduced, thereby affecting the relevant performance of the whole contact material.
Furthermore, before the second layer of mixed powder is sprayed to the first sintered body and before the third layer of mixed powder is sprayed to the second sintered body, roughening treatment is respectively carried out on the first surface of the sintered body and the second surface of the sintered body by using a suction type sand blasting machine, wherein the adopted sand is brown corundum, and the roughness of the surfaces of the first sintered body and the second sintered body is increased by roughening the first surface of the sintered body and the second surface of the sintered body, so that the binding force between the first surface of the sintered body and the second layer of mixed powder and between the third layer of mixed powder and the second sintered body is improved, and the mechanical strength of the whole gradient contact material and the thermal conductivity of each layer are improved.
Further, rare earth oxides are respectively added into three layers of mixed powder with sequentially reduced tungsten content, wherein the weight of the rare earth oxides added into each layer accounts for 2%, 1% and 0.5% of the weight percentage of the mixed powder of each layer, the rare earth oxides can be lanthanum oxide and cerium oxide, and because the copper content of the three layers of mixed powder is sequentially increased from inside to outside, the heat conductivity of each layer is sequentially enhanced, in order to ensure the uniformity of the heat conductivity of the finished product of the whole contact material, the rare earth oxides with different high heat conductivities are required to be added into each layer, so that the ratio of copper to tungsten in each layer of mixed powder of raw materials can be ensured, the integral uniformity of the heat conductivity can be improved, the heat conductivity can be improved.
Furthermore, when the rare earth oxide is added into the three layers of mixed powder, the mixed powder and the rare earth oxide are paved until the added rare earth oxide is paved, the bottommost layer and the topmost layer are both the mixed powder, the rare earth oxide is uniformly paved in the mixed powder, the mixing uniformity is improved, the phenomena of uneven heat conduction and local temperature rise caused by uneven mixing of the mixed powder and the rare earth oxide are avoided, and the performance of the contact material is reduced.
The invention has the beneficial effects that: the invention provides a preparation method of a copper-tungsten gradient material electrical contact, which has the following advantages:
1. the invention obtains the copper-tungsten gradient electrical contact material in gradient change by continuously changing the proportion of the copper and the tungsten, the high-tungsten part has high arc ablation resistance and fusion welding resistance, and the high-copper part has good electric conduction and thermal conduction.
2. According to the invention, the first layer with the highest tungsten content is used as the matrix template, and then mixed powder with different tungsten contents is subjected to layered spraying by using a plasma spraying technology, so that the phenomenon that three layers of powder with different tungsten contents are sintered simultaneously to generate mutual fusion, the copper-tungsten proportion of each layer is influenced, the arc ablation resistance of the high tungsten layer and the fusion welding resistance of the high copper layer are reduced, and the performance of the whole contact material is influenced.
3. According to the invention, the rare earth oxide is added into each layer of mixed powder, so that the heat conduction performance of the contact material is improved, and the content of the added rare earth oxide is adjusted according to the change of the copper content in the mixed powder, so that the ratio of copper to tungsten in each layer of mixed powder of raw materials can be ensured, and the integral heat conduction uniformity can be improved.
4. According to the invention, the graphite mold is cleaned before being used, the graphite mold is soaked by hydrofluoric acid, a natural oxidation film on the surface of the graphite mold can be removed, and ultrasonic cleaning is combined to facilitate removal of metal and organic pollutants embedded in an oxidation layer, so that the influence of the pollutants on the purity of the prepared electric contact is avoided, and the performance of the electric contact is reduced.
Drawings
FIG. 1 is a gold phase diagram of the CuW80 transition CuW60 of the present invention;
FIG. 2 is a gold phase diagram of the transition CuW70 of CuW80 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
As shown in fig. 1 and 2, a method for manufacturing an electrical contact made of a copper-tungsten gradient material mainly includes the following steps:
step 1: the weight percentage is as follows: respectively taking 80% of tungsten powder, 20% of electrolytic copper powder, 70% of tungsten powder, 30% of electrolytic copper powder, 60% of tungsten powder and 40% of electrolytic copper powder to prepare mixed powder of three components, wherein the particle size of the tungsten powder is 2 microns, and the mesh number of the electrolytic copper powder is-200, then respectively pouring the mixed powder of the three components into a planetary high-energy ball mill for ball milling to obtain mixed powder with different tungsten contents, and taking argon as protective gas, wherein the ball-material ratio is 20:1, the rotating speed is 600r/min, and the ball milling time is 8; tungsten powder with the particle size of 2um and electrolytic copper powder with the mesh number of-200 are selected to meet the composite use requirement, and the electric contact made of the thinner or thicker powder has poor electric arc burning resistance and cannot meet the use requirement because the influence of the particle size of the powder on the performance of the tungsten-copper electric contact material is obvious;
step 2: dividing tungsten powder and copper powder subjected to high-energy ball milling into three layers according to the sequence that the tungsten content is reduced from bottom to top, pouring the three layers into a graphite mold layer by layer, putting the graphite mold into a discharge plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 30MPa, heating to 1200 ℃, keeping the temperature for 3min, cooling along with the furnace to obtain a sintered body, and obtaining a copper-tungsten gradient electrical contact material with gradient change by continuously changing the proportion of the copper and tungsten, wherein the high-tungsten part has high arc ablation resistance and fusion welding resistance, and the high-copper part has good electric conductivity and thermal conductivity, and compared with a single-component copper-tungsten electrical contact in the traditional method, the high-pressure breaking capacity and the service life of the copper-tungsten electrical contact part are improved;
and step 3: and carrying out surface machining on the sintered body to obtain the copper-tungsten gradient material.
Example 2
As shown in fig. 1 and 2, a method for manufacturing an electrical contact made of a copper-tungsten gradient material mainly includes the following steps:
step 1: respectively taking 80% of tungsten powder, 20% of electrolytic copper powder, 70% of tungsten powder, 30% of electrolytic copper powder, 60% of tungsten powder and 40% of electrolytic copper powder to prepare mixed powder of three components, wherein the particle size of the tungsten powder is 4 microns, and the mesh number of the electrolytic copper powder is-200, then respectively pouring the mixed powder of the three components into a planetary high-energy ball mill for ball milling to obtain mixed powder with different tungsten contents, and taking argon as protective gas, wherein the ball-to-material ratio is 30:1, the rotating speed is 700r/min, and the ball milling time is 12 hours; the tungsten powder with the particle size of 4um and the electrolytic copper powder with the mesh number of-200 are selected to meet the composite use requirement, the electric contact made of the thinner or thicker powder has poor arc burning resistance and cannot meet the use requirement because the particle size of the powder has obvious influence on the performance of the tungsten-copper electric contact material, and the electric contact made of the thinner or thicker powder has poor arc burning resistance and cannot meet the use requirement because the particle size of the powder has obvious influence on the performance of the tungsten-copper electric contact material;
step 2: dividing tungsten powder and copper powder subjected to high-energy ball milling into three layers according to the sequence that the tungsten content is reduced from bottom to top, pouring the three layers into a graphite mold layer by layer, putting the graphite mold into a discharge plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 35MPa, heating to 1220 ℃, keeping the temperature for 3.5min, cooling along with the furnace to obtain a sintered body, and obtaining a copper-tungsten gradient electrical contact material with gradient change by continuously changing the proportion of the copper and the tungsten, wherein the high-tungsten part has high arc ablation resistance and fusion welding resistance, and has good electric conductivity and thermal conductivity, and compared with a single-component copper-tungsten electrical contact in the traditional method, the high-pressure breaking capacity and the service life of the copper-tungsten electrical contact part are improved;
and step 3: and carrying out surface machining on the sintered body to obtain the copper-tungsten gradient material.
Example 3
As shown in fig. 1 and 2, a method for manufacturing an electrical contact made of a copper-tungsten gradient material mainly includes the following steps:
step 1: respectively taking 80% of tungsten powder, 20% of electrolytic copper powder, 70% of tungsten powder, 30% of electrolytic copper powder, 60% of tungsten powder and 40% of electrolytic copper powder to prepare mixed powder of three components, wherein the particle size of the tungsten powder is 6 microns, the mesh number of the electrolytic copper powder is-200, then respectively pouring the mixed powder of the three components into a planetary high-energy ball mill for ball milling to obtain mixed powder with different tungsten contents, argon is used as protective gas, wherein the ball-material ratio is 40:1, the rotating speed is 800r/min, the ball milling time is 14 hours, the tungsten powder with the particle size of 6 microns and the electrolytic copper powder with the mesh number of-200 are selected to be used in a composite mode, and the electric contact made of thinner or thicker powder has poor arc burning loss resistance and cannot meet the use requirement due to the obvious influence of the particle size of the powder on the performance of the tungsten-copper electric contact material;
step 2: dividing tungsten powder and copper powder subjected to high-energy ball milling into three layers according to the sequence that the tungsten content is reduced from bottom to top, pouring the three layers into a graphite mold layer by layer, placing the graphite mold into a discharge plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 40MPa, heating to 1280 ℃, keeping the temperature for 4min, cooling along with the furnace to obtain a sintered body, and obtaining a copper-tungsten gradient electrical contact material with gradient change by continuously changing the proportion of the copper and the tungsten, wherein the high-tungsten part has high arc ablation resistance and fusion welding resistance, and has good electric conductivity and thermal conductivity;
and step 3: and carrying out surface machining on the sintered body to obtain the copper-tungsten gradient material.
Example 4
This embodiment is substantially the same as embodiment 2 except that:
the particle size of the tungsten powder selected in the step 1 is 7um, and the mesh number of the electrolytic copper powder is-200.
Example 5
This example is substantially the same as example 4, except that:
the particle size of the tungsten powder selected in the step 1 is 8um, and the mesh number of the electrolytic copper powder is-200.
Example 6
This example is substantially the same as example 5 except that:
in the step 2, before the ball-milled powder is poured into a graphite mold, the graphite mold is cleaned, and the specific treatment process comprises the following steps: firstly, a graphite mould is placed into a cleaning tank added with hydrofluoric acid for soaking for 4 hours, then the soaked graphite mould is placed into an ultrasonic cleaning tank for cleaning for 15min, then the cleaned graphite mould is taken out and is washed for 30min by a washing water gun, finally, the graphite mould after being cleaned is placed into a drying box for drying and is cooled to normal temperature, the graphite mould is soaked by the hydrofluoric acid, a natural oxidation film on the surface of the graphite mould can be removed, and meanwhile, ultrasonic cleaning is combined, so that metal and organic pollutants embedded in an oxidation layer can be removed, the condition that the prepared electrical contact purity is influenced by the pollutants is avoided, and the performance of the electrical contact is reduced.
Example 7
This embodiment is substantially the same as embodiment 6 except that:
and (3) carrying out layer-by-layer sintering treatment when the three layers of mixed powder are sintered in the step (2), wherein the specific sintering process is as follows: firstly, pouring a first layer of mixed powder into a graphite mould, putting the graphite mould into a plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 48MPa, heating to 1250 ℃, preserving heat for 4min, cooling along with the furnace to obtain a first sintered body, spraying a second layer of mixed powder onto the surface of the preheated sintered body by using a plasma spraying technology to obtain a second sintered body, repeatedly spraying a third layer of mixed powder onto the surface of the second sintered body by using the plasma spraying technology to obtain a third sintered body, finally cooling to room temperature, preparing a first layer with the highest tungsten content as a matrix template, and respectively spraying powder with different tungsten contents by using the plasma spraying technology to avoid the simultaneous sintering of the three layers of powder with different tungsten contents to cause mutual melting among the powder of each layer, influence the copper-tungsten ratio of each layer, reduce the arc resistance of a high tungsten layer and the fusion welding ablation resistance of a high copper layer, thereby affecting the relevant properties of the overall contact material.
And (3) respectively roughening the first surface of the sintered body and the second surface of the sintered body by using a suction type sand blasting machine before spraying the second layer of mixed powder to the first sintered body and before spraying the third layer of mixed powder to the second sintered body, wherein the adopted sand is brown corundum, and roughening the first surface of the sintered body and the second surface of the sintered body is performed to increase the surface roughness of the first surface of the sintered body and the second surface of the sintered body, so that the binding force between the first surface of the sintered body and the second layer of mixed powder and between the third layer of mixed powder and the second sintered body is improved, and the mechanical strength of the whole gradient contact material and the thermal conductivity.
Example 8
This example is substantially the same as example 7 except that:
lanthanum oxide is respectively added into three layers of mixed powder with sequentially reduced tungsten content, wherein the weight of the lanthanum oxide added into each layer accounts for 2%, 1% and 0.5% of the weight of the mixed powder of each layer, the thickness of each layer of a finished product after each layer is sintered is sequentially reduced from inside to outside, staggered laying steps of the mixed powder and the lanthanum oxide are adopted until the added lanthanum oxide is laid, the bottommost layer and the topmost layer are both mixed powder, rare earth oxide lanthanum oxide is uniformly laid in the mixed powder to increase the mixing uniformity, the phenomena of uneven heat conduction and local temperature rise caused by uneven mixing of the mixed powder and the lanthanum oxide are avoided, the performance of the contact material is reduced, the heat conductivity of each layer is sequentially enhanced as the copper content in the three layers of mixed powder is sequentially increased from inside to outside, and lanthanum oxide with different contents and high heat conductivities is required to be added into each layer in order to ensure the uniformity of the heat conduction of a finished product, the ratio of copper and tungsten in each layer of mixed powder of raw materials can be guaranteed, the integral heat conduction uniformity can be improved, the heat conductivity can be improved, and the market prospect is achieved.
Test examples
The copper-tungsten alloy contact materials prepared by the methods of the embodiments 1 to 8 of the present invention were tested for copper content, conductivity, hardness and density, respectively, and compared with the national standard, the results of the performance test of the alloy part are shown in table 1, and the performance parameters of the copper-tungsten gradient material of the national standard are shown in table 2.
Table 1: performance meter of copper-tungsten gradient electrical contact material
Table 2: performance table of national standard copper-tungsten gradient material
| Copper content% | Conductance Ms/m | Hardness HB | Density g/cm3 | |
| CuW80 | 20±2 | ≥20 | 220 | 15.15 |
| CuW70 | 30±2 | 24.4 | 175 | 13.8 |
| CuW60 | 40±2 | 27 | 140 | 12.75 |
As can be seen from the comparison of tables 1 and 2, the copper-tungsten gradient materials prepared by examples 1 to 8 of the present invention have better copper content, conductivity, hardness and density than the national standard for CuW80, CuW70 and CuW 60.
Claims (2)
1. The preparation method of the copper-tungsten gradient material electrical contact is characterized by mainly comprising the following steps of:
step 1: the weight percentage is as follows: preparing 40-90% of tungsten powder and the balance of copper powder into mixed powder with different components respectively, pouring the mixed powder with different components into a planetary high-energy ball mill respectively for ball milling to obtain mixed powder with different tungsten contents, and taking argon as protective gas, wherein the ball-material ratio is 20: 1-50: 1, the rotating speed is 600-1000 r/min, and the ball milling time is 8-24 h;
step 2: dividing the tungsten powder and the copper powder subjected to high-energy ball milling into a plurality of layers according to the sequence that the tungsten content is reduced from bottom to top, pouring the layers into a graphite mold layer by layer, putting the graphite mold into a discharge plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 30-50MPa, heating to 1200-1300 ℃, preserving heat for 3-5min, and cooling along with the furnace to obtain a sintered body;
and step 3: carrying out surface machining on the sintered body to obtain a copper-tungsten gradient material;
before powder after ball milling is poured into a graphite mold, the graphite mold is cleaned firstly, and the specific treatment process comprises the following steps: firstly, placing a graphite mold into a cleaning tank added with hydrofluoric acid for soaking for 3-5h, then placing the soaked graphite mold into an ultrasonic cleaning tank for cleaning for 10-20min, then taking out the cleaned graphite mold, washing the cleaned graphite mold for 25-35min by using a washing water gun, finally, placing the cleaned graphite mold into a drying box for drying, and cooling to normal temperature;
in the step 2, the tungsten powder and the copper powder after the high-energy ball milling are divided into three layers according to the sequence that the tungsten content is reduced from bottom to top, wherein the tungsten content in each layer of mixed powder is respectively 80%, 70% and 60%;
the three-layer mixed powder in the step 2 can be subjected to layer-by-layer sintering treatment during sintering, and the specific sintering process is as follows: firstly, pouring a first layer of mixed powder into a graphite mold, putting the graphite mold into a plasma sintering furnace, vacuumizing and pressurizing, introducing pulse direct current when the pressure reaches 45-50MPa, heating to 1200-1300 ℃, preserving heat for 3-5min, cooling along with the furnace to obtain a first sintered body, spraying a second layer of mixed powder onto the surface of the preheated sintered body by using a plasma spraying technology to obtain a second sintered body, spraying a third layer of mixed powder onto the surface of the second sintered body by repeatedly using the plasma spraying technology to obtain a second sintered body, and finally cooling to room temperature;
spraying a second layer of mixed powder to the front of the first sintered body and spraying a third layer of mixed powder to the front of the second sintered body, and roughening the surfaces of the first sintered body and the second sintered body by using a suction type sand blasting machine respectively, wherein the adopted sand is brown corundum;
respectively adding rare earth oxides into three layers of mixed powder with sequentially reduced tungsten content, wherein the weight of the rare earth oxide added in each layer accounts for 2%, 1% and 0.5% of the weight of the mixed powder in each layer.
2. The method for preparing the copper-tungsten gradient material electrical contact according to claim 1, wherein the particle size of the tungsten powder in the step 1 is 2-8um, and the copper powder is electrolytic copper powder of-200 meshes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010326243.XA CN111636023B (en) | 2020-04-23 | 2020-04-23 | Preparation method of copper-tungsten gradient material electrical contact |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010326243.XA CN111636023B (en) | 2020-04-23 | 2020-04-23 | Preparation method of copper-tungsten gradient material electrical contact |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111636023A CN111636023A (en) | 2020-09-08 |
| CN111636023B true CN111636023B (en) | 2021-04-23 |
Family
ID=72324651
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010326243.XA Active CN111636023B (en) | 2020-04-23 | 2020-04-23 | Preparation method of copper-tungsten gradient material electrical contact |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111636023B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112593105B (en) * | 2020-10-19 | 2022-02-08 | 陕西斯瑞新材料股份有限公司 | Process for preparing copper-tungsten gradient functional material by utilizing gradient copper-tungsten alloy powder |
| CN112974814A (en) * | 2021-04-25 | 2021-06-18 | 陕西斯瑞新材料股份有限公司 | Method for preparing regenerated copper-tungsten alloy powder |
| CN112872356B (en) * | 2021-05-06 | 2021-07-23 | 陕西斯瑞新材料股份有限公司 | Method for improving strength of copper-tungsten and copper bonding surface |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2597018B2 (en) * | 1989-12-26 | 1997-04-02 | 日本原子力研究所 | Insulating member and electrical component using the same |
| JP4014248B2 (en) * | 1997-03-21 | 2007-11-28 | 本田技研工業株式会社 | Method for producing functionally gradient material |
| CN1180907C (en) * | 2003-06-18 | 2004-12-22 | 北京科技大学 | Tungsten-copper gradient heat sink material and its preparing method |
| CN100588483C (en) * | 2008-05-16 | 2010-02-10 | 西安理工大学 | Preparation of tungsten copper electric contact material with high electric-abrasion resistance |
| CN103194712B (en) * | 2012-01-09 | 2015-10-21 | 中国科学院上海硅酸盐研究所 | A kind of tungsten-copper composite material of high thermal conductivity is as the application of tungsten copper heat-sink and electronic package material |
| CN106011510B (en) * | 2016-08-05 | 2018-02-02 | 陕西斯瑞新材料股份有限公司 | The preparation method of copper tungsten contact material |
| CN106180653B (en) * | 2016-08-05 | 2018-01-12 | 陕西斯瑞新材料股份有限公司 | The method that discharge plasma sintering prepares copper tungsten contact material |
| CN109702200A (en) * | 2019-02-28 | 2019-05-03 | 中国地质大学（武汉） | A kind of W/Cu functionally graded material and preparation method thereof |
-
2020
- 2020-04-23 CN CN202010326243.XA patent/CN111636023B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111636023A (en) | 2020-09-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111636023B (en) | Preparation method of copper-tungsten gradient material electrical contact | |
| CN103489665B (en) | The preparation method of high breaking low-voltage electrical apparatus contact material, the preparation method of high breaking low-voltage electrical apparatus composite contact material | |
| CN111411254B (en) | Tungsten-reinforced copper composite material and preparation method thereof | |
| CN101834077B (en) | Method for manufacturing pure copper/copper chromium alloy composite contact material | |
| CN111834135B (en) | MAX @ MOm/AOn electrical contact enhanced phase material, composite electrical contact material and preparation method | |
| CN111519076A (en) | Diamond particle reinforced metal matrix composite material and preparation method and application thereof | |
| CN106735207B (en) | A kind of preparation method of high-compactness Cu/CuCr gradient composites | |
| CN112981164B (en) | Preparation method of diamond reinforced metal matrix composite material with high reliability and high thermal conductivity | |
| CN105132726A (en) | Copper-chromium contact material suitable for contactor and preparing method of copper-chromium contact material | |
| CN114774759B (en) | Layered gradient SiC ceramic reinforced iron-based wear-resistant material and preparation method thereof | |
| CN111489899B (en) | Preparation method of silver tungsten carbide electrical contact material | |
| CN105385883A (en) | Electrical contact material and preparation method thereof | |
| CN1180907C (en) | Tungsten-copper gradient heat sink material and its preparing method | |
| CN113523300A (en) | Method for laser 3D printing of tungsten-copper alloy special-shaped component and component thereof | |
| CN114525438B (en) | Tungsten copper composite material and preparation method thereof | |
| CN111778424A (en) | Preparation method of effectively controllable skeleton with multi-polar-hole structure | |
| CN102632237B (en) | Method for manufacturing pure copper/ copper-chromium alloy composite contact material by spray deposition | |
| CN105463238A (en) | Cu-Cr electrical contact material and preparation method thereof | |
| CN108015276A (en) | One kind enhancing phase gradient distribution infiltration class silver-based electric contact material and preparation method thereof | |
| CN102290260B (en) | Electric contact and preparation method thereof | |
| CN113976885A (en) | Preparation method of tungsten-copper functionally graded material | |
| CN108774698A (en) | A kind of Aludirome plate and preparation method thereof | |
| CN113755735B (en) | Titanium carbide porous ceramic preform, brake disc and preparation method | |
| CN113787192B (en) | Preparation method of W-Cu composite plate with Cu phases distributed in finger-shaped gradient manner | |
| CN111468736A (en) | Silver metal oxide electric contact material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |