CN105551860B - A kind of preparation method of Ni-coated graphite alkene/silver nickel electric contact material - Google Patents
A kind of preparation method of Ni-coated graphite alkene/silver nickel electric contact material Download PDFInfo
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- CN105551860B CN105551860B CN201610106140.6A CN201610106140A CN105551860B CN 105551860 B CN105551860 B CN 105551860B CN 201610106140 A CN201610106140 A CN 201610106140A CN 105551860 B CN105551860 B CN 105551860B
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- nickel
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- graphite alkene
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Classifications
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- 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
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- 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
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C5/00—Alloys based on noble metals
- C22C5/06—Alloys based on silver
Abstract
The present invention relates to the preparation method of Ni-coated graphite alkene/silver nickel electric contact material, step includes：The nickel plating of graphene magnetically controlled DC sputtering, Ni-coated graphite alkene and silver powder and nickel powder ball milling mix powder, cold moudling, sintering, machine-shaping, wherein 0.1 5.0wt% Ni-coated graphite alkene, 10% 40wt% nickel powders, surplus are that silver powder ball milling mixes powder.Electrical contact material prepared by this method while not reducing its electric conductivity, thermal conductivity, improves hardness, wearability and the resistance fusion welding of silver by the way that Ni-coated graphite alkene reinforcement is added in silver powder, nickel powder.
Description
Technical field
The present invention relates to a kind of preparation method of electrical contact material more particularly to a kind of Ni-coated graphite alkene/silver nickel electric contacts
The preparation method of material.
Background technology
AgNi materials have good processing performance, preferable wear resistance, contact resistance it is low and stablize etc. excellent properties
It is used on various small current relays, control switch and probe of contactor, but since its resistance fusion welding is poor, shadow
Its broader applications is rung.Have studies have shown that graphite is added to melting welding and the bonding that can prevent contact in silver-colored nickel material, drop
The contact resistance of low contact improves electric conductivity and resistance fusion welding.
Existing patent（Publication number 102808098A）A kind of preparation method of silver/nickel/graphite contact material is disclosed, is adopted
With the method for chemical plating, coated with silver is prepared into intermediate composite particles again after Graphite Coating nickel, then using the mixed powder of tradition,
Sintering process prepares silver/nickel/graphite contact material.But the graphite plating process complex process from preparation process, plating solution is to people
Body has certain pollution, and coating quality is not easy to control, is not suitable for industrialized production.Meanwhile adding graphite and using micron order,
Particle size is larger, reduces the mechanical strength of electrical contact material to a certain extent, while resistance to arc erosion is poor, it is difficult to obtain
The electrical contact material that comprehensive performance satisfies the use demand.
Existing patent document（Publication number 102385938A）, disclose a kind of metal matrix graphene composite electrical contact material and
Preparation method, contact material include the graphene of 0.02-10wt%, remaining is metal matrix material.Since graphene increases
The addition of strong phase makes the composited contact material have conductive, thermal conductivity more better than other reinforced phase composited contact materials
It can be with higher hardness and wearability.But it is reducing agent because using poisonous and hazardous hydrazine hydrate, it is difficult to meet environmental requirement.
Therefore, the preparation that electrical contact is realized with the production technology of a kind of environmental protection, low cost, makes material property further carry
It rises.
Invention content
Present invention aims at providing a kind of preparation method of Ni-coated graphite alkene/silver nickel electric contact material, by silver powder,
Ni-coated graphite alkene reinforcement is added in nickel powder, while not reducing its electric conductivity, thermal conductivity, improves hardness, the wearability of silver
And resistance fusion welding.
The technical solution that the present invention proposes in order to solve the above problem：
A kind of preparation method of Ni-coated graphite alkene/silver nickel electric contact material, which is characterized in that include the following steps：
（1）Using direct current magnetron sputtering process, Ni-coated graphite alkene is made in deposited metal nickel on the surface of graphene.Graphene is N
Layer, N 1-10.It is first polished with fine sandpaper before the nickel target installation that purity is 99.99%, removes surface film oxide, then use acetone
Cleaning is dried, and is carried out 5 minutes pre-sputterings before Deposited By Dc Magnetron Sputtering, is separated target and graphene using baffle, and target is removed
The metal oxide on material surface and other impurity ensure the purity of follow-up graphene surface deposition nickel film.Magnetically controlled DC sputtering is heavy
Product equipment concrete technology be：Target is the nickel target that purity is 99.99%, reaches 0.1*10 in vacuum degree-3-1.0*10-3When Pa,
It is passed through the argon gas of purity 99.99%, operating air pressure is in 0.8-1.2Pa, and sputtering power is in 80-120W, sedimentation time 5-20min.
（2）By 0.1-5.0wt% Ni-coated graphite alkene, 10%-40wt% nickel powders, surplus is that silver is put into the mixed powder of ball mill ball milling, nickel
- 450 mesh of 300 mesh of Powder Particle Size, -300 mesh of 200 mesh of silver powder granularity.During ball milling mixes powder, using alumina balls grinding jar and agate
Ball, ratio of grinding media to material 3:1, it vacuumizes 10 minutes, then be passed through the argon gas protection of purity 99.99%, 150-350 revs/min of rotating speed, per ball
Mill 10-15 minutes stops 5 minutes, exchanges rotation clockwise and anticlockwise, amounts to and mixes 4-8 hours powder time.Alternately ball milling is mixed
Powder is conducive to the full and uniform mixing of metal powder.
To prevent the oxidation of copper, ball grinder need to vacuumize before ball milling, and be passed through argon gas protection.In the ball milling parameter of the present invention
In range, the distribution of graphene and metal alloy mixed-powder can be controlled well.
（3）By step（2）Powder is put into cold moudling in mold, pressure 150-350MPa, dwell time 2-5 point after mixing
Clock is sintered under the hydrogen shield of purity 99.9%, 800-1000 DEG C of sintering temperature, soaking time 2-4 hours.
（4）It squeezes or Ni-coated graphite alkene/silver nickel electric contact material is made in rolling mill practice.
The step（4）It is middle to squeeze cold-rolled sintered blank, squeeze 600-850 DEG C of temperature, extrusion ratio 50：1-150：
1, the proximate matter of needs is made.
The step（4）It is middle to roll cold-rolled sintered blank, 600-850 DEG C of rolling temperature, rolling reduction 80%-
90%, proximate matter, plank, tubing is made.
The present invention useful achievement be：
（1）Silver-colored graphene of the nickel electric contact material addition with ultra-high conductivity, thermal conductivity, hardness, can reduce contact
Contact resistance, improve thermal conductivity and resistance fusion welding.
（2）Nickel is deposited using magnetron sputtered deposition technology on the surface of graphene, the structure of formation improves graphene and base
The interface cohesion of body silver, good interface bonding energy can make contact material obtain higher electric conductivity, thermal conductivity, also avoid
Aggregation of the graphene nano powder in matrix silver ensures graphene distributing homogeneity in the base, while coating process is without dirt
Dye, deposition process are easy to control.
（3）Nickel is added in silver matrix, improves hardness, resistance fusion welding and the inoxidizability of material.
Specific implementation mode
Embodiment 1
（1）Using direct current magnetron sputtering process in graphene（The number of plies is 1-10 layers）Surface deposited metal nickel is prepared into nickel plating stone
Black alkene.It is first polished with fine sandpaper before the nickel target installation that purity is 99.99%, removes surface film oxide, then cleaned with acetone,
It dries, carries out 5 minutes pre-sputterings before Deposited By Dc Magnetron Sputtering, separated target and graphene using baffle, remove target table
The metal oxide in face and other impurity ensure the purity of follow-up graphene surface deposition nickel film.Sputtering parameter is as follows：Vacuum degree
Reach 0.1*10-3When Pa, it is passed through the argon gas of purity 99.99%, gas pressure in vacuum 0.8Pa, sputtering power 120W, sedimentation time is
5min。
（2）Ni-coated graphite alkene：Nickel powder：Silver powder presses 0.1：10：89.9 weight ratio is fitted into ball mill, using alumina balls
Ink tank and agate ball, ratio of grinding media to material 3:1.Ball grinder first vacuumize be passed through again 99.99% argon gas protection, 150 revs/min of rotating speed, ball
During mill mixes powder, ball milling clockwise 15 minutes stops 5 minutes, and ball milling counterclockwise 15 minutes stops 5 minutes, according to this alternately work
Make, amounts to and mix 4 hours powder time, obtain mixed uniformly powder.
（3）By step（2）Powder is put into mold after mixing, and cold moudling, dwell time 5 are carried out at pressure 150MPa
Minute, cold moudling part, 800 DEG C of sintering temperature, soaking time 4 hours are sintered under hydrogen shield.
（4）Extrusion process, 600 DEG C of temperature, extrusion ratio 50：1, Ni-coated graphite alkene/silver nickel electric contact material is made.
Embodiment 2
（1）Using direct current magnetron sputtering process in graphene（The number of plies is 1-10 layers）Surface deposited metal nickel is prepared into nickel plating stone
Black alkene.It is first polished with fine sandpaper before the nickel target installation that purity is 99.99%, removes surface film oxide, then cleaned with acetone,
It dries, carries out 5 minutes pre-sputterings before Deposited By Dc Magnetron Sputtering, separated target and graphene using baffle, remove target table
The metal oxide in face and other impurity ensure the purity of follow-up graphene surface deposition nickel film.Sputtering parameter is as follows：Vacuum degree
Reach 1.0*10-3When Pa, it is passed through the argon gas of purity 99.99%, gas pressure in vacuum 1.2Pa, sputtering power 80W, sedimentation time is
20min。
（2）Ni-coated graphite alkene：Nickel powder：Silver powder presses 5：40：55 weight ratio is fitted into ball mill, using alumina balls ink tank
And agate ball, ratio of grinding media to material 3:1.Ball grinder first vacuumize be passed through again 99.99% argon gas protection, 350 revs/min of rotating speed, ball milling is mixed
During powder, ball milling clockwise 10 minutes stops 5 minutes, and ball milling counterclockwise 10 minutes stops 5 minutes, works alternatively according to this,
It amounts to and mixes 8 hours powder time, obtain mixed uniformly powder.
（3）By step（2）Powder is put into mold after mixing, and cold moudling, dwell time 2 are carried out at pressure 350MPa
Minute, cold moudling part, 1000 DEG C of sintering temperature, soaking time 2 hours are sintered under hydrogen shield.
（4）Extrusion process, 850 DEG C of temperature, extrusion ratio 150：1, Ni-coated graphite alkene/silver nickel electric contact material is made.
Embodiment 3
（1）Using direct current magnetron sputtering process in graphene（The number of plies is 1-10 layers）Surface deposited metal nickel is prepared into nickel plating stone
Black alkene.It is first polished with fine sandpaper before the nickel target installation that purity is 99.99%, removes surface film oxide, then cleaned with acetone,
It dries, carries out 5 minutes pre-sputterings before Deposited By Dc Magnetron Sputtering, separated target and graphene using baffle, remove target table
The metal oxide in face and other impurity ensure the purity of follow-up graphene surface deposition nickel film.Sputtering parameter is as follows：Vacuum degree
Reach 0.3*10-3When Pa, it is passed through the argon gas of purity 99.99%, gas pressure in vacuum 1.0Pa, sputtering power 110W, sedimentation time is
5min。
（2）Ni-coated graphite alkene：Nickel powder：Silver powder presses 2：10：88 weight ratio is fitted into ball mill, using alumina balls ink tank
And agate ball, ratio of grinding media to material 3:1.Ball grinder first vacuumize be passed through again 99.99% argon gas protection, 200 revs/min of rotating speed, ball milling is mixed
During powder, ball milling clockwise 10 minutes stops 5 minutes, and ball milling counterclockwise 10 minutes stops 5 minutes, works alternatively according to this,
It amounts to and mixes 5 hours powder time, obtain mixed uniformly powder.
（3）By step（2）Powder is put into mold after mixing, and cold moudling, dwell time 3 are carried out at pressure 200MPa
Minute, cold moudling part, 850 DEG C of sintering temperature, soaking time 3 hours are sintered under hydrogen shield.
（4）Extrusion process, 750 DEG C of temperature, extrusion ratio 100：1, Ni-coated graphite alkene/silver nickel electric contact material is made.
Embodiment 4
Ni-coated graphite alkene：Nickel powder：Silver powder presses 2：20：78 weight ratio is fitted into ball mill, and other conditions parameter is the same as implementation
Example 3, using rolling machine-shaping, 600 DEG C of temperature, Ni-coated graphite alkene/silver nickel electric contact material is made in deformation rate 80%.
Embodiment 5
Ni-coated graphite alkene：Nickel powder：Silver powder presses 5：20：75 weight ratio is fitted into ball mill, and other conditions parameter is the same as implementation
Example 3, using rolling machine-shaping, 850 DEG C of temperature, Ni-coated graphite alkene/silver nickel electric contact material is made in deformation rate 90%.
Comparative example 1
Silver powder：Nickel powder presses 20：80 weight ratio is packed into ball mill and mixes powder, and other parameters are made silver-colored nickel electricity and touch with embodiment 3
Head material.
Comparative example 2
Silver powder：Nickel powder presses 10：90 weight ratio is packed into ball mill and mixes powder, and other parameters are made silver-colored nickel electricity and touch with embodiment 3
Head material.
Comparative example 3
Graphene is by weight with silver powder：0.5：99.5 are packed into ball mill grinding, and other parameters are made with embodiment 3
The silver-colored nickel electric contact material of graphene enhancing.
Manufactured composite material parameters such as following table：
Ni-coated graphite alkene is added, the silver-colored nickel electric contact material of graphene enhancing is made, graphene is not added with comparative example 1,2
Manufactured silver-colored nickel electric contact material is compared, though hardness, conductivity all significantly improve or conductivity does not improve, hardness significantly carries
It is high.Compared with the silver-colored nickel electric contact material being added made of graphene in comparative example 3, hardness significantly improves, and obtains preferably comprehensive
Close performance.
Claims (7)
1. a kind of preparation method of Ni-coated graphite alkene/silver nickel electric contact material, which is characterized in that include the following steps：
（1）Using direct current magnetron sputtering process, Ni-coated graphite alkene is made in deposited metal nickel on the surface of graphene；
（2）By 0.1-5.0wt% Ni-coated graphite alkene, 10%-40wt% nickel powders, surplus is that silver is put into the mixed powder of ball mill ball milling, nickel powder grain
Spend -450 mesh of 300 mesh, -300 mesh of 200 mesh of silver powder granularity；
（3）By step（2）Powder is put into cold moudling in mold after mixing, sintering；
（4）It squeezes or Ni-coated graphite alkene/silver nickel electric contact material is made in rolling mill practice.
2. preparation method according to claim 1, which is characterized in that step（1）Middle graphene is N layers, N 1-10.
3. preparation method according to claim 1, which is characterized in that step（1）Middle Deposited By Dc Magnetron Sputtering equipment
Concrete technology is：Target is the nickel target that purity is 99.99%, reaches 0.1*10 in vacuum degree-3-1.0*10-3When Pa, it is passed through purity
99.99% argon gas, operating air pressure is in 0.8-1.2Pa, and sputtering power is in 80-120W, sedimentation time 5-20min.
4. preparation method according to claim 1, which is characterized in that step（2）During middle ball milling mixes powder, using oxidation
Aluminium ball grinding jar and agate ball, ratio of grinding media to material 3:1, it vacuumizes 10 minutes, then be passed through the argon gas protection of purity 99.99%, rotating speed 150-
350 revs/min, every ball milling 10-15 minutes stops 5 minutes, exchanges rotation clockwise and anticlockwise, and it is small to amount to mixed powder time 4-8
When.
5. preparation method according to claim 1, which is characterized in that step（3）Middle cold moudling pressure 150-350MPa,
Dwell time 2-5 minute is sintered under the hydrogen shield of purity 99.9%, 800-1000 DEG C of sintering temperature, and soaking time 2-4 is small
When.
6. preparation method according to claim 1, which is characterized in that step（4）In cold-rolled sintered blank extrusion process at
Type squeezes 600-850 DEG C of temperature, extrusion ratio 50：1-150：1.
7. preparation method according to claim 1, which is characterized in that step（4）In the rolling of cold-rolled sintered blank be processed into
Type, 600-850 DEG C of rolling temperature, rolling reduction 80%-90%.
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| CN108251674A (en) * | 2018-02-26 | 2018-07-06 | 华南理工大学 | A kind of plating nickel on surface graphene reinforced aluminum matrix composites and its hot extrusion preparation method |
| CN108941966B (en) * | 2018-08-20 | 2019-11-12 | 苏州大学张家港工业技术研究院 | A kind of graphene strengthens the welding method of steel Al dissimilar materials weld seam |
| CN109207780B (en) * | 2018-09-17 | 2020-07-14 | 南昌大学 | Rolling method for reinforcing AZ31 magnesium alloy |
| CN114101666B (en) * | 2021-09-03 | 2023-08-01 | 叶浩博 | Graphene-based silver-saving electrical contact material and manufacturing method thereof |
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