CN102268566B - High conductivity and high wear resistance copper-molybdenum alloy material and preparation method thereof - Google Patents
High conductivity and high wear resistance copper-molybdenum alloy material and preparation method thereof Download PDFInfo
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- CN102268566B CN102268566B CN 201010604960 CN201010604960A CN102268566B CN 102268566 B CN102268566 B CN 102268566B CN 201010604960 CN201010604960 CN 201010604960 CN 201010604960 A CN201010604960 A CN 201010604960A CN 102268566 B CN102268566 B CN 102268566B
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Abstract
The invention relates to a high conductivity and high wear resistance copper-molybdenum alloy material. The material of the invention comprises a matrix alloy Cu, a friction component Al2O3, a lubrication component MoS2, a high temperature component Mo, and copper. A product (the material) is prepared by preparing a mixed powder material through mixing powders of Al2O3, MoS2, Mo and copper according to a proportion and filling into a stainless steel grinding pot of a high energy bowl mill, sending the mixed powder material to a press machine, prepressing into a blank, sending the blank to a cold isostatic press machine to press, and sending the statically pressed blank to a vacuum sintering furnace to sinter. In the invention, quality fraction scopes of above components are determined on the basis of massive experiments, and the experiments prove that ingredients in the component scopes allow reactions to be stably and smoothly carried out, and optimal performances of the material of the invention to be realized.
Description
Technical field
The present invention relates to a kind of Cu-base composites, specifically a kind of copper molybdenum alloy material with high conductivity, high-wearing feature and preparation method thereof.
Background technology
Progress and development along with science and technology, at a high speed, large electric current is widely applied by electric friction materials, as at the various conductive contacts of the various switches of field of track traffic, power transmission and transformation system, communication system, various contactors, plug conductive component etc. in the industrial control unit (ICU).This class friction-conductive friction material has following characteristic: friction contact and conductive contact coexistence, work-ing life, reliability and conductivity require to lay equal stress on, and require material to possess simultaneously friction-conduction integrated function.
In the current-carrying friction pair, be attended by the problems such as frictional wear and conductive contact be bad.The friction of material can cause the problems such as the loss, frictional heating of energy, and material property is worsened, and the related products life-span reduces.And wearing and tearing can cause material unaccounted-for (MUF), reduction in work-ing life, contact reliability to reduce, and the materials'use life-span is difficult to satisfy basic demand under high life, the nothing copy service condition.The bad problems such as electrical efficiency decline and reliability reduction that cause of conductive contact.The bad ratio of contact loss of guide rail/slide block that makes of conductive contact increases, less than 5%, and China is because problems such as the design of wire/slide plate and line managements such as the ballastless track ratio of contact loss, and ratio of contact loss is up to 15% at present, current carrying quality is low, the performance of restriction electric locomotive active power.
The starting the arc is one of another principal feature of current-carrying frictional wear.Exist strong dependency between electric arc and the friction and wear characteristic: arc damage causes surface in contact to destroy, and causes surface integrity and inhomogeneity decrease; And incomplete Surface Contact will cause the obvious deterioration of electrical contact performance, and contact resistance is increased, and starting the arc tendency increases, and the performance that this has reduced again surfacing has conversely promoted the further deterioration of friction and wear behavior.Therefore, the performance of raising friction/current-carrying material must continue to improve the Surface Contact state.Add the friction and wear behavior that solid lubricant can improve friction/current-carrying material in the metallic matrix.
Copper has high electroconductibility, thermal conductivity and good processing characteristics, but the fusing point of fine copper, room temperature strength and hot strength are lower, is difficult to satisfy harsh working condition requirement.The method of traditional raising copper alloy intensity is alloying, can obtain the tensile strength of 1350MPa such as 48% cold deformation after the Cu-Be alloy QBe2 timeliness, but specific conductivity only is 19.5%IACS.
Existing copper alloy is difficult to take into account high conductivity and high strength, and complex intensifying not only can obviously not reduce the electroconductibility of copper matrix, also can improve simultaneously room temperature and the high-temperature behavior of matrix, become the main reinforcement means that obtain high strength, combarloy based composites.Main method has:
(1) Al
2O
3Dispersion strengthening copper alloy
In the copper matrix, directly add or generate by certain technique original position the Second Phase Particle of disperse distribution, the dispersion-strengthened of comprehensive utilization working hardening and Second Phase Particle, obtain the high strength of materials, solute atoms and the impurity atoms content of the solid solution attitude in the reduce copper matrix make it have the novel copper-based matrix material of a class of the electroconductibility that approaches with fine copper simultaneously.This wherein, Al
2O
3Enhanced granule not only can obviously not reduce the electroconductibility of matrix, and because its room temperature and high-temperature behavior of strengthening matrix is remarkable, uses and be obtained emphasis.But along with Al
2The raising of O3 particle add-on, material is when wear resistance improves, and electric conductivity significantly descends.
(2) graphite/copper self-lubricating material
Take copper based powder metallurgy material as the basis, add the graphite material that is easy to shear, form one deck at friction surface and continue/spontaneous lubricant film, improve touching act, significantly improve current-carrying and friction and wear behavior.Studies show that: the stable friction factor of graphite copper product, current-carrying efficient and current-carrying stability all are significantly higher than the ordinary copper sill.Yet copper and graphite are immiscible, even chemical reaction does not occur in the time of 1280 ℃ yet, add that copper and graphite proportion differ larger etc., and batch mixing is uneven when causing forming materials.It is a kind of pseudoalloy that copper is combined with graphite, and the material interface defective is many, has seriously restricted the raising of its intensity and lubricity.In addition, copper/graphite self-lubricating material bending strength is low, poor toughness, and particularly after temperature was more than or equal to 300 ℃, its matrix strength obviously descended, and wear resistance reduces.
(3) MoS
2/ copper radical self-lubricating materials
In the sintering process under the hydrogen shield, the lubricant component MoS in the Cu-base composites
2React with matrix copper, generate sulfide and the metal M o of copper molybdenum sulphide, Cu; And with MoS
2Content increases, and sintered product changes regularly.Because Cu-MoS
2Contain molybdenumdisulphide in the matrix material, can fully provide and additional solid lubricant, make lubricated membrane repair and Breakage Processes reach running balance; The sulfide and the body material that add Cu have good chemical affinity, be easy to stick together by its solid lubricant film that forms and blapharoplast, increased the mechanical engagement effect of solid lubricant film and matrix, make solid lubricant film and matrix tack better, bonding strength is higher, and cracky does not come off.
(4) molybdenum-copper alloy
Molybdenum and alloy thereof have good physics, chemistry and mechanical property, and it has: fusing point height, the high and low coefficient of expansion of hot strength, low specific heat, good heat-conductivity conducting performance, good corrosion resistance and wear resistance at elevated temperature, fabulous thermal shock resistance and heat-resistant anti-fatigue performance.Molybdenum be in the metal except the metals such as gold and silver, copper, electricity is led with heat conductance than one of best element, thereby become the advanced material that application prospect is arranged very much at high-technology fields such as electronic industry, national defense industry, aerospace industry, nuclear industry, become a kind of important raw material and irreplaceable strategic materials in the national economy, had vast potential for future development.
Utilize copper and molybdenum premium properties separately, traditional Mo-Cu alloy is as the vacuum contact head of electron trade, conductive radiator element, solid dynamic seal, the strengthening rib of sliding friction, the water cooled electrode head of High Temperature Furnaces Heating Apparatus, and edm electrode etc. is widely applied.These alloys mainly comprise: the molybdenum base alloys such as Mo-30Cu and Mo-50Cu.Because the Cu of low-expansion Mo and high heat conductance is a kind of pseudoalloy by the Mo-Cu alloy that powder metallurgy process makes, and in the alloy take molybdenum element as main, copper content is low, so the electroconductibility of alloy descends a lot than fine copper.
Can be found out by above-mentioned research, copper base alloy and the molybdenum alloy of research can't reach following performance index at present: the tensile strength＞400MPa of alloy material, hardness＞90HB, (speed greater than 300m/s, electric current greater than 1kA) material friction coefficient＜0.2 under the condition of high-speed slide and large electric current, specific conductivity 〉=70%IACS.The material that has good high conduction like this, high-wear resistance in various copper bases and the molybdenum base material there is not yet report.Therefore developing a kind of copper molybdenum alloy with high conductivity, high-wear resistance seems very necessary and urgent.
Summary of the invention
The object of the present invention is to provide a kind of copper molybdenum alloy with high conductivity, wear resistance at elevated temperature, distributing friction component, lubricant component and high temperature constituent element of disperse in the alloy, when guaranteeing high-conductivity, constituent element plays anti-attrition, wear-resistant effect.
The present invention realizes that the technical scheme that above-mentioned purpose is taked is: a kind of copper molybdenum alloy material of high conduction high abrasion, raw material is by matrix alloy: Cu, friction component: Al
2O
3, lubricant component: MoS
2, high temperature constituent element: Mo forms, the massfraction of each material is: Al
2O
30.1-0.5%, MoS
20.1-0.5%, Mo 1-5%, all the other are copper.Al in the alloy of preparation
2O
3, MoS
2Be uniformly distributed in the copper matrix with Mo.
High conduction wear-resistant copper molybdenum alloy contains Al with what interior redox made
2O
3Cu powder, MoS
2With Mo powder reducing material, be prepared from through high-energy ball milling machinery alloying, premolding, isostatic cool pressing, vacuum reducing sintering process.
Concrete preparation method is as follows:
One, with massfraction is the Al of 0.1-0.5%
2O
3, massfraction is the MoS of 0.1-0.5%
2, massfraction is that Mo and the massfraction of 1-5% is the powder of the copper of 94-98.8%, after preparing in proportion, in the stainless-steel grinding tank of the high energy ball mill of packing into, mixed grinding 5-25h, vacuum operating, vacuum tightness is not less than 10
-2Pa, the dry argon gas protection makes the mixed powder material;
Two, with the mixed powder material, send into pressing machine, be pressed in advance blank, dwell time 8-15min;
Three, with the blank after the precompressed, send in the cold isostatic press, suppress pressure 180-220MPa, pressurize 8-20min;
Four, with the blank behind the step 3 static pressure, send into sintering in the vacuum sintering furnace, sintering temperature 950-1050 ℃, sintering time 1-2h, hydrogen shield, 10 ℃/min of heat-up rate comes out of the stove, and makes product.
The invention has the beneficial effects as follows:
1, among the present invention, the massfraction scope of above-mentioned each constituent element is determined on the lot of experiments basis, experimental results show that the batching in this composition range, and reacting balance is carried out smoothly, and makes material property best.
2, adopt the high conduction wear-resistant copper molybdenum alloy of the present invention's preparation, its component can be: Al
2O
3Massfraction be 0.1-0.5%, MoS
2Massfraction be 0.1-0.5%, the massfraction of Mo is 1-5%, all the other are Cu.
3, the height of preparation conduction wear-resistant copper molybdenum alloy material excellent property: tensile strength 〉=400MPa, hardness 〉=90HB, (speed greater than 300m/s, electric current greater than 1kA) material friction coefficient＜0.2 under the condition of high-speed slide and large electric current, specific conductivity 〉=70%IACS.The preparation production process is simple, be easy to control, the enhanced granule size, is evenly distributed.
4, in the high conduction wear-resistant copper molybdenum alloy material of the present invention's preparation, Al
2O
3Played mutually wear-resistant effect, MoS
2Played mutually the anti-attrition effect, Mo is mutually tiny, even dispersion is distributed in the Cu matrix, both there be not to form the network structure that electroconductibility is had larger negative impact, can give full play to again the disperse enhancement of Mo phase, the alloy of preparation has excellent physics and mechanical property, so the present invention has very wide application prospect.
Embodiment
A kind of copper molybdenum alloy material of high conductivity high-wearing feature, raw material is by matrix alloy: Cu, friction component: Al
2O
3, lubricant component: MoS
2Form with high temperature constituent element: Mo.In the alloy of preparation, Al
2O
3Massfraction be 0.1-0.5%, MoS
2Massfraction be 0.1-0.5%, the massfraction of Mo is 1-5%, all the other are copper.Al in the alloy of preparation
2O
3, MoS
2Be uniformly distributed in the copper matrix with Mo.
High conduction wear-resistant copper molybdenum alloy contains Al with what interior redox made
2O
3Cu powder, MoS
2With Mo powder reducing material, be prepared from through high-energy ball milling machinery alloying, premolding, isostatic cool pressing, vacuum reducing sintering process.
Concrete preparation method is as follows:
One, with massfraction is the Al of 0.1-0.5%
2O
3, massfraction is the MoS of 0.1-0.5%
2, massfraction is that Mo and the massfraction of 1-5% is the powder of the copper of 94-98.8%, after preparing in proportion, in the stainless-steel grinding tank of the high energy ball mill of packing into, mixed grinding 5-25h, vacuum operating, vacuum tightness is not less than 10
-2Pa, the dry argon gas protection makes the mixed powder material;
Two, with the mixed powder material, send into pressing machine, be pressed in advance blank, dwell time 8-15min;
Three, with the blank after the precompressed, send in the cold isostatic press, suppress pressure 180-220MPa, pressurize 8-20min;
Four, with the blank behind the step 3 static pressure, send into sintering in the vacuum sintering furnace, sintering temperature 950-1050 ℃, sintering time 1-2h, hydrogen shield, 10 ℃/min of heat-up rate comes out of the stove, and makes product.
Embodiment 1
Copper molybdenum alloy material of a kind of high conductivity high-wearing feature and preparation method thereof: the raw material of employing is: contain A
L2O
3The Cu powder, MoS
2Powder, pure molybdenum powder; The concrete proportioning of the massfraction of each constituent element is as follows:
Al
2O
3： 0.1%
MoS
2： 0.1%
Mo： 1％
All the other are Cu, foreign matter content＜0.1%.
The above-mentioned powder that proportions is packed in the stainless-steel grinding tank of high energy ball mill, mixed running 15h, in the powder mixed grinding process, vacuum operating, vacuum tightness 10
-2Pa is filled with dry Ar gas and protects rotating speed 1400r/min;
Mixed powder behind the high-energy ball milling is premolding under the 100T pressing machine, pressurize 10min;
Blank after the premolding is suppressed at cold isostatic press, pressure 180MPa, pressurize 10min;
Sintering in vacuum sintering furnace, 950 ℃ of sintering temperatures, sintering time 1.5h, vacuum tightness 10
-2Pa, hydrogen shield, 10 ℃/min of heat-up rate comes out of the stove, and makes product.
Embodiment 2
What present embodiment prepared is high conduction wear-resistant copper molybdenum alloy material, and the raw material of employing is: contain Al
2O
3The Cu powder, MoS
2Powder, pure molybdenum powder; The concrete proportioning of the massfraction of each constituent element is as follows:
Al
2O
3： 0.2%
MoS
2： 0.2%
Mo： 2％
All the other are Cu, foreign matter content ﹤ 0.1%.
The above-mentioned powder that proportions is packed in the stainless-steel grinding tank of high energy ball mill, mixed running 20h, in the powder mixed grinding process, vacuum operating, vacuum tightness 10
-3Pa is filled with dry Ar gas and protects rotating speed 1500r/min;
Mixed powder behind the high-energy ball milling is premolding under the 100T pressing machine, pressurize 10min;
Blank after the premolding is suppressed at cold isostatic press, pressure 200MPa, pressurize 10min;
Sintering in vacuum sintering furnace, 1000 ℃ of sintering temperatures, sintering time 2h, vacuum tightness 10
-3Pa, hydrogen shield, 10 ℃/min of heat-up rate, coming out of the stove makes product.
Embodiment 3
What present embodiment prepared is high conduction wear-resistant copper molybdenum alloy material, and the raw material of employing is: contain Al
2O
3The Cu powder, MoS
2Powder, pure molybdenum powder; The concrete proportioning of the massfraction of each constituent element is as follows:
Al
2O
3： 0.3%
MoS
2： 0.3%
Mo： 3％
All the other are Cu, foreign matter content ﹤ 0.1%.
The above-mentioned powder that proportions is packed in the high energy ball mill stainless-steel grinding tank, mixed running 22h, in the powder mixed grinding process, vacuum operating, vacuum tightness 10
-3Pa is filled with dry Ar gas and protects rotating speed 1600r/min;
Mixed powder behind the high-energy ball milling is premolding under the 100T pressing machine, pressurize 12min;
Blank after the premolding is suppressed at cold isostatic press, pressure 200MPa, pressurize 15min;
Sintering in vacuum sintering furnace, 1050 ℃ of sintering temperatures, sintering time 2h, vacuum tightness 10
-3Pa, hydrogen shield, 10 ℃/min of heat-up rate comes out of the stove, and makes product.
Embodiment 4
What present embodiment prepared is high conduction wear-resistant copper molybdenum alloy material, and the raw material of employing is: contain Al
2O
3The Cu powder, MoS
2Powder, pure molybdenum powder; The concrete proportioning of the massfraction of each constituent element is as follows:
Al
2O
3： 0.3%
MoS
2： 0.5%
Mo： 5％
All the other are Cu, foreign matter content ﹤ 0.1%.
The above-mentioned powder that proportions is packed in the high energy ball mill stainless-steel grinding tank, mixed running 24h, in the powder mixed grinding process, vacuum operating, vacuum tightness 10
-3Pa is filled with dry Ar gas and protects rotating speed 1600r/min;
Mixed powder behind the high-energy ball milling is premolding under the 100T pressing machine, pressurize 15min;
Blank after the premolding is suppressed at cold isostatic press, pressure 220MPa, pressurize 15min;
Sintering in vacuum sintering furnace, 1050 ℃ of sintering temperatures, sintering time 2h, vacuum tightness 10
-3Pa, hydrogen shield, 10 ℃/min of heat-up rate comes out of the stove, and makes product.
Claims (2)
1. the copper molybdenum alloy material of a high conduction high abrasion, it is characterized in that: raw material is by matrix alloy: Cu, friction component: Al
2O
3, lubricant component: MoS
2, high temperature constituent element: Mo forms, the massfraction of each raw material is: Al
2O
30.1-0.5%, MoS
20.1-0.5%, Mo 1-5%, all the other are copper; Al in the alloy of preparation
2O
3, MoS
2Be uniformly distributed in the copper matrix with Mo.
2. the copper molybdenum alloy material preparation method of a kind of high conduction high abrasion according to claim 1 is characterized in that step is as follows:
One, with massfraction is the Al of 0.1-0.5%
2O
3, massfraction is the MoS of 0.1-0.5%
2, massfraction is that Mo and the massfraction of 1-5% is the powder of the copper of 94-98.8%, after preparing in proportion, in the stainless-steel grinding tank of the high energy ball mill of packing into, mixed grinding 5-25h, vacuum operating, vacuum tightness is not less than 10
-2Pa, the dry argon gas protection makes the mixed powder material;
Two, with the mixed powder material, send into pressing machine, be pressed in advance blank, dwell time 8-15min;
Three, with the blank after the precompressed, send in the cold isostatic press, suppress pressure 180-220MPa, pressurize 8-20min;
Four, with the blank behind the step 3 static pressure, send into sintering in the vacuum sintering furnace, sintering temperature 950-1050 ℃, sintering time 1-2h, hydrogen shield, 10 ℃/min of heat-up rate comes out of the stove, and makes product.
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|---|---|---|---|
| CN 201010604960 CN102268566B (en) | 2010-12-25 | 2010-12-25 | High conductivity and high wear resistance copper-molybdenum alloy material and preparation method thereof |
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| CN102268566B true CN102268566B (en) | 2013-03-20 |
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| CN104480342B (en) * | 2014-12-12 | 2017-09-29 | 贵州新安航空机械有限责任公司 | A kind of corrosion-resistant copper-based brake material of great friction coefficient and preparation method thereof |
| CN104762498B (en) * | 2015-04-14 | 2017-03-01 | 中国工程物理研究院材料研究所 | A kind of high temperature insostatic pressing (HIP) preparation method of high densification molybdenum-copper |
| CN105256168B (en) * | 2015-10-26 | 2017-05-03 | 三峡大学 | Copper-based graphite self-lubricating composite material and preparing method thereof |
| CN110093530A (en) * | 2019-06-10 | 2019-08-06 | 河南科技大学 | It is a kind of high to lead wear-resistant copper based composites and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101041870A (en) * | 2007-04-26 | 2007-09-26 | 昆明理工大学 | Preparation method of copper radical self-lubricating materials |
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| JPS6032699B2 (en) * | 1978-09-27 | 1985-07-30 | 住友電気工業株式会社 | Heat-resistant conductive material and its manufacturing method |
| AT413034B (en) * | 2003-10-08 | 2005-10-15 | Miba Gleitlager Gmbh | ALLOY, ESPECIALLY FOR A GLIDING LAYER |
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| CN101041870A (en) * | 2007-04-26 | 2007-09-26 | 昆明理工大学 | Preparation method of copper radical self-lubricating materials |
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| JP昭55-44558A 1980.03.28 |
| JP特表2007-507605A 2007.03.29 |
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