Summary of the invention
The object of the invention is to overcome the deficiency of prior art; A kind of novel high speed train pantograph sliding block material is provided; When being applied on the bullet train conducting system, can adapt to high temperature, at a high speed, severe environment such as heavy duty, large impact, insufficient lubrication, satisfy each item performance index of bullet train slide block.
The present invention realizes that through following technical scheme the composition of this alloy material consists of copper (Cu), titanium silicon-carbon (Ti
3SiC
2), graphite (C), its quality percentage composition of each element is following:
Ti
3SiC
2 7~13%,
C 2.9-3.1%,
The Cu surplus.
Preferably, said titanium silicon-carbon (Ti
3SiC
2) it accounts for, and to mix back copper based powder metallurgy material quality percentage composition of the present invention be 10%.
Preferably, said graphite (C) confirms that it accounts for mixing back copper based powder metallurgy material quality percentage composition of the present invention is 3%, and promptly 3% content of graphite is the best content of graphite of copper based powder metallurgy material of the present invention.
The selection of the powder particle magnitude range of each elementary composition is not that the present invention contributes prior art, and according to existing conventional theoretical, powder is thin more, and pressed density is big more; Behind the sintering, hole is little, organizes finer and close; Performance is better, but powder is thin more, and required pressing force is also big more.The powder particle scope is selected in 200 conventional orders to all applicable between 600 orders.
Said copper is tesseral system, and copper type cubic crystal structure is arranged, and has advantages of good abrasion, ductility, heat conduction and electroconductibility, is to use the widest conduction current-collecting member at present.
Said graphite is six side's laminate structures, have characteristics such as favorable conductive, heat conduction, anticorrosive, radiation hardness, high-low temperature resistant, but matter is crisp, and intensity is low.Be widely used in the electro-conductive material field, outstanding electricity was led because it had both kept, thermal conductivity, had solid lubricant performance and anti-melting welding effect again.
Said titanium silicon-carbon (Ti
3SiC
2) be the ceramic layered material of a kind of novel tertiary, have metal and ceramic performance concurrently.High-yield strength, HMP, high thermal stability and hot strength and good anti-oxidant, thermal shock resistance and corrosion resistance nature; Have simultaneously high heat conductance and specific conductivity again; Machining property is good, and good high-temperature plasticity is than graphite lower frictional coefficient and better self-lubricating property.
The present invention adopts traditional powder metallurgical technique method preparation: carry out compacting sintering technology according to technique scheme alloy ingredient proportioning; The copper titanium silicon-carbon powdered graphite metallurgical material of producing can satisfy bullet train pantograph slide block performance requriements, and material property characteristics of the present invention are following:
Impelling strength |
Tensile strength |
Density |
Rockwell Hardness |
Frictional coefficient |
Electric conductivity |
1.8~2.7J/cm
2 |
90~110MPa |
5.5~6.5g/cm
3 |
70~80HB |
0.38 |
74%-75%IACS |
The pantograph sliding block material of being processed by material of the present invention has good antifriction performance, self-lubricating property, conductivity, anti-electrical arc erosion performance, weather resistance and higher strength and stiffness; And complete processing is simple; Machining property is good, and is with low cost.When this kind material is applied on the bullet train conducting system; Can adapt to high temperature, at a high speed, severe environment such as heavy duty, large impact, insufficient lubrication; Realized each item performance index of bullet train slide block, safe works better that guarantees train and the operation cost that reduces high-speed railways have been had great realistic meaning.
The metallurgical sliding material of copper titanium silicon-carbon powdered graphite of the present invention is at first succeedd on the high-speed railway circuit and is used; The ring header, armature, rotor, the empty frame lead of electric locomotive etc. that progressively its range of application are expanded to contact, the mover of the lead frame of unicircuit, various welding electrode, electric switch are on this basis located, so that fully realize the use value and the economic benefits of this kind material.
Innovative point of the present invention:
(1) through theoretical analysis and practical exploration, prepared the metallurgical sliding block material of copper titanium silicon-carbon powdered graphite, be applied to the bullet train system, all satisfy practical application request through this material each item performance of lot of experiment validation.
(2), illustrated the rule of the metallurgical sliding material weave construction of copper titanium silicon-carbon powdered graphite through the preparation and the research of material.
(3), verified the friction and wear behavior and the microscopic mechanism of copper titanium silicon-carbon graphite alloy material through frictional wear and microcosmic microscope experiment (friction and wear behavior test and SEM observe pattern).Test through quadrature analysis; Utilization report to the leadship after accomplishing a task analyze with the range analysis method to slip velocity, current density and load influence effect, influence in proper order and significance is discussed; And infer the reciprocal effect between each factor, and inquire into the complicacy of these material current-carrying wearing and tearing.
Embodiment
The invention is further illustrated by the following examples.
Embodiment 1 (preferred embodiment)
(1) batch mixing: (maximum capacity: 100kg), rotating speed is 34r/min, whenever at a distance from the sense of rotation of 15 minutes change mixers, lets the material thorough mixing to adopt the metal-powder mixer.
(2) experiment material: copper powder (Cu), 400 orders, 87%;
Titanium silicon-carbon (Ti
3SiC
2), 200 orders, 10%;
Graphite (C), 200 orders, 3%;
(3) first pressing: adopt 240 tons of pressure to carry out first pressing.
(4) sintering: adopt the ladder-elevating temperature mode, temperature curve as shown in Figure 9.
(5) cooling: in process of cooling, always adopt hydrogen shield, up to cooling to 200
oBelow the C.
(6) following process: to the test block of moulding carry out necessary car, cut, precision work and surface treatment such as brill.
The material that present embodiment obtains is compared with existing same type of material; Possess good comprehensive physicals, and can realize the control of technology to material property, friction and wear behavior is excellent; Not only significantly reduce the wear rate of self, and the friction pair lead is also had the certain protection effect.
The performance characteristics that material possesses is following:
Impelling strength |
Tensile strength |
Density |
Rockwell Hardness |
Frictional coefficient |
Electric conductivity |
2.7J/cm
2 |
113MPa |
6.5g/cm
3 |
82HB |
0.38 |
75%IACS |
Referring to Fig. 1 is the metallographic structure photo of present embodiment material, and as can be seen from Figure 1, copper matrix (clear zone) sintering is intact, and it is block that pattern is net, Ti
3SiC
2With Graphite Distribution wherein.Granular graphite is big, and graphite and matrix copper bonding force are poor slightly, and reuniting behind the sintering is distributed in copper bound circle, and more being prone in the wear process come off, it is secondary to get into the wear interface lubrication friction.Ti
3SiC
2Grain is little, is uniformly distributed in the copper matrix, Ti
3SiC
2Grain is better than graphite with copper matrix bond performance, and the distribution of copper matrix has guaranteed that material has conductivity preferably.
Ti
3SiC
2Material is uniformly distributed in the copper matrix, plays strengthening effect, and when sintering temperature reached 900~1000 ℃, the copper grain edges had been in the semi-melting state, can receive rigidity Ti in the flow process
3SiC
2The inhibition that particle is stronger exists under the situation of external pressure, and inhibition is obvious further, simultaneously Ti
3SiC
2Particle also can slide in copper particle gap, forms like Fig. 1 pattern.Graphite matter is soft, flows the clump shape growth in copper particle gap with softening copper.
The stereoscan photograph on present embodiment fret wear surface; As can beappreciated from fig. 4, slight plow wearing and tearing have taken place in material surface, and hard particles is the body material of work hardening or oxidation; The TiC hard crystallization phases that hard particles that minority titanium silicon-carbon sintering gathers or friction generate; The polishing scratch direction is consistent, regional area surface smoothing, graphite and Ti
3SiC
2Sporadicly be distributed in substrate surface, play self-lubricating effect, improve wear resistance.Find peeling phenomenon by Fig. 5, peeling off the hole mainly is graphite material, and graphite and copper basal body binding force are relatively poor; In the wear process, the engaging friction interface that comes off easily, lubricate; And titanium silicon carbon material and copper matrix bond are tightr, and it is also more even to distribute, and the hole is peeled off in difficult formation.Therefore material of the present invention has good friction and wear behavior to its friction pair copper silver osculatory.
Through general analysis can specifically confirming graphite and Ti
3SiC
2Material can be known by general figure from Fig. 6, and graphite (Fig. 7 is an A aterrimus part) and titanium silicon-carbon (Fig. 8 is B ash color part) sporadicly are distributed in substrate surface, play self-lubricating effect, improve wear resistance, and wherein granular graphite is big, assembles to distribute Ti
3SiC
2Grain is little, uniform distribution.
Embodiment 2
The present embodiment preparation method is with embodiment 1.
Experiment material: copper powder (Cu), 400 orders, 90%;
Titanium silicon-carbon (Ti
3SiC
2), 200 orders, 7%;
China ink (C), 200 orders, 3%.
The material that present embodiment obtains is compared with existing same type of material; Possess good comprehensive physicals, and can realize the control of technology to material property, friction and wear behavior is excellent; Not only significantly reduce the wear rate of self, and the friction pair lead is also had the certain protection effect.
The performance characteristics that material possesses is following:
Impelling strength |
Tensile strength |
Density |
Rockwell Hardness |
Frictional coefficient |
Electric conductivity |
2.4J/cm
2 |
102MPa |
6.5g/cm
3 |
72HB |
0.38 |
74%IACS |
Referring to Fig. 2 is the metallographic structure photo of present embodiment material, and as can be seen from Figure 2, copper matrix (clear zone) is net distribution, Ti
3SiC
2With Graphite Distribution wherein.Granular graphite is big, assembles to be distributed in copper bound circle, and it is poor slightly that graphite combines with matrix copper.Ti
3SiC
2Grain is little, is uniformly distributed in the copper matrix, Ti
3SiC
2Grain is functional with the copper matrix bond, and the distribution of copper matrix can guarantee that material has conductivity preferably.
Can know that by above-mentioned analysis when sintering temperature reached 900~1000 ℃, being in semi-melting state copper grain edges can flow, and rigidity Ti
3SiC
2Particle can hinder this flow process, and because copper content is big than embodiment 1, Ti
3SiC
2The particle inhibition is limited, so form like Fig. 2 pattern.Graphite matter is soft, in the flow process, and the clump shape growth in copper particle gap.
Embodiment 3
The present embodiment preparation method is with embodiment 1.
Experiment material: copper powder (Cu), 400 orders, 84%;
Titanium silicon-carbon (Ti
3SiC
2), 200 orders, 13%;
China ink (C), 200 orders, 3%.
The material that present embodiment obtains is compared with existing same type of material; Possess good comprehensive physicals, and can realize the control of technology to material property, friction and wear behavior is excellent; Not only significantly reduce the wear rate of self, and the friction pair lead is also had the certain protection effect.
The performance characteristics that material possesses is following:
Impelling strength |
Tensile strength |
Density |
Rockwell Hardness |
Frictional coefficient |
Electric conductivity |
1.8J/cm
2 |
89MPa |
5.5g/cm
3 |
70HB |
0.38 |
74%IACS |
Referring to Fig. 3 is the metallographic structure photo of present embodiment material, as can be seen from Figure 3, the subregion, copper matrix (clear zone) is by Ti
3SiC
2Particle is separated, and powder is particulate state, graphite and Ti
3SiC
2Uniform distribution is mechanical bond between the powder particle, and sintering effect is not as embodiment 1, and this distribution of copper matrix has determined material to have hardness, density, tensile strength and the impelling strength lower with respect to embodiment 1.Can know Ti by above-mentioned analysis
3SiC
2Content is excessive possibly to cause copper matrix sintering insufficient and to hinder flowing property obvious.
Infer Ti thus
3SiC
2Content is excessive very big to the material property influence, should strict control Ti in the design process
3SiC
2Content.
Can know embodiment 3 samples, Ti by 3 embodiment analyses
3SiC
2Content is big, and behind the sintering, subregion copper can't normally form the sintering neck, and powder is particulate state, graphite and Ti
3SiC
2Uniform distribution is mechanical bond between the powder particle, and sintering effect is all not obvious, makes comprehensive physicals on the low side than other formula materials.Embodiment 1 is obvious with embodiment 2 material sintering effects, tangible sintering neck is arranged, graphite and Ti
3SiC
2Uniform distribution rises and strengthens and lubricant effect.Simultaneously, embodiment 2 material Ti
3SiC
2Content is few than embodiment 1 material, and strengthening effect is not as embodiment 1 material, although the sintering success, hardness is low than embodiment 1 material.Draw Ti thus
3SiC
2Content should be less than 13%, infer simultaneously to have a best Ti
3SiC
2The stagnation point of content, so that the hardness maximization, the wear resistance of raising friction materials, and this optimum point should be around 10%.
Embodiment 4
The present embodiment preparation method is with embodiment 1.
Experiment material: copper powder (Cu), 400 orders, 89.1%;
Titanium silicon-carbon (Ti
3SiC
2), 200 orders, 8%;
China ink (C), 200 orders, 2.9%.
The material that present embodiment obtains is compared with existing same type of material; Possess good comprehensive physicals, friction and wear behavior is excellent, not only significantly reduces the wear rate of self; And the friction pair lead also had the certain protection effect, can satisfy bullet train pantograph slide block performance requriements.
Embodiment 5
The present embodiment preparation method is with embodiment 1.
Experiment material: copper powder (Cu), 400 orders, 86.9%;
Titanium silicon-carbon (Ti
3SiC
2), 200 orders, 10%;
China ink (C), 200 orders, 3.1%.
The material that present embodiment obtains is compared with existing same type of material; Possess good comprehensive physicals, friction and wear behavior is excellent, not only significantly reduces the wear rate of self; And the friction pair lead also had the certain protection effect, can satisfy bullet train pantograph slide block performance requriements.
Sliding block material has mainly experienced the evolution of metal slider, pure carbon slide plate, powder metallurgy slide plate, metal-impregnated carbon slide and carbon-fibre composite slide plate in research and application facet.The carbon slide plate is low to lead abrasion, but extension lead work-ing life, physical strength is low, is prone to fracture, falls the piece phenomenon, and it is big to cause the pantograph and catenary fault probability, and work-ing life is short, and the scope of application is limited.Metal-impregnated carbon slide theoretically, is the pantograph pan of at present ideal copper conductive section; Has electric property preferably; Basically solved the low problem of carbon slide plate physical strength, wear resisting property greatly improves, and can solve the too fast problem of lead abrasion at all; But anti-impact force is not enough, piece occurs falling, needs shaping in the use, selling at exorbitant prices, and maintenance cost is high.
For current-collecting member, conductivity is particularly important, and copper based powder metallurgy material has been taken into account intensity and conductivity.At present, to the development and the exploitation of copper based powder metallurgy material, mainly be matrix with copper, add a small amount of pivot metal-powder of strengthening, and add graphite as lubricated pivot.With Ti
3SiC
2Relevant slide block product mainly contains as follows:
1)Ti
3SiC
2-?Cu
Because Ti
3SiC
2About 60%, its bending strength and Young's modulus are very high, and resistivity is very low, but Ti
3SiC
2Resolve into hard impurity TiC and Ti easily
3SiC
2The high temperature aggregate all can have very big influence to polishing machine.
2)Ti
3SiC
2
Ternary layered compound Ti
3SiC
2Have the characteristic of pottery and metal concurrently.Have the conduction, heat conduction of metalloid material and be prone to the lightweight of characteristic such as processing and similar stupalith, characteristic such as anti-oxidant, high temperature resistant.But Ti
3SiC
2Fragility is bigger, and mechanical property such as shock-resistant and conductivity all can't match in excellence or beauty with copper based powder metallurgy material behind the sintering.
3) Cu-copper facing Ti
3SiC
2-C
Adopt copper-plating technique at ceramic particle Ti
3SiC
2Copper coating improves copper facing Ti
3SiC
2With the carbon/carbon-copper composite material bonding properties.At present, this material is more to measuring mechanical property, and seldom relates to the current-carrying wear test.With the increase of copper facing amount, the electroconductibility of matrix material, hardness and bending strength significantly improve, and still most of this materials are compared than material of the present invention, and the graphite prescription is too high, Ti
3SiC
2Content is low excessively, and complete processing exists than big difference simultaneously, and performance difference is bigger.