CN109563002A - The preparation method of silicon carbide aluminum-base composite structural member and SiC reinforcement prefabricated component - Google Patents
The preparation method of silicon carbide aluminum-base composite structural member and SiC reinforcement prefabricated component Download PDFInfo
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Abstract
The preparation method of a kind of silicon carbide aluminum-base composite structural member and SiC reinforcement prefabricated component, this method comprises: providing the silicon-carbide particle of at least two different average particle sizes；The silicon-carbide particle of the different average particle sizes of predetermined ratio is uniformly mixed；Bonding agent is added into silicon-carbide particle after mixing to be kneaded, and is formed by isostatic cool pressing technology, SiC reinforcement prefabricated component is made；By Vacuumgas pressure infiltration method, make the melt containing aluminium and the SiC reinforcement prefabricated component that the silicon carbide aluminum-base composite structural member be made.In this way, complex parts can be prepared or provide technical support for it, and is of less demanding to the plasticity of powder.
Description
Technical field
This application involves technical field of composite materials more particularly to a kind of silicon carbide aluminum-base composite structural member and silicon carbide to increase
The preparation method of strong prefabricated component.
Background technique
High-performance light structural material occupies an important strategic position in economy and national defense construction, wherein as matrix
Lightweight structural material mainly has tri- kinds of alloys of A1, Mg, Ti, and reinforcement material mainly has silicon carbide SiC, A12O3、BC4、TiB2Deng.
Carbonization sial AlSiC composite material is widely used in aviation boat with its excellent thermophysical property and mechanical mechanics property at present
It, the fields such as Electronic Packaging, optical instrument, sports equipment.
In the prior art one, the preparation method of AlSiC composite material is: mixed using SiC powder and paraffin based binder
Synthesize uniform feeding, feeding injection moulding on injection machine after pelletizing, gained SiC preform, then by molten
It is pre-sintered at a temperature of 1000~1150 DEG C after agent and thermal debinding, finally by pressureless infiltration method in 1100~1200 DEG C of temperature
Under, N2The solution of Al alloy molten is penetrated into SiC skeleton in atmosphere, so that obtaining has the SiC/Al of high-volume fractional multiple
Condensation material part.
But present inventor has found in long-term R&D process, and in the above method, powder injection-molded preparation
When complex parts, it is desirable that injection powder has good mobility, needs to be added a large amount of organic binders, the removing of binder
Journey is link most difficult in entire technique, and degreasing time is long, and the large quantity of exhaust gas that when degreasing generates pollutes the environment, simultaneously
Powder size is generally just suitble to powder injection molding process requirement in 0.5~20um.
Summary of the invention
The application is mainly solving the technical problems that provide a kind of preparation method and one of silicon carbide aluminum-base composite structural member
The preparation method of kind SiC reinforcement prefabricated component, can be prepared complex parts or provide technical support for it, and to powder
The plasticity of body is of less demanding.
In order to solve the above technical problems, the technical solution that the application uses is: providing a kind of silicon carbide aluminum-base composite
The preparation method of structural member, which comprises the silicon-carbide particle of at least two different average particle sizes is provided；By predetermined ratio
The silicon-carbide particles of the different average particle sizes be uniformly mixed；Into silicon-carbide particle after mixing add bonding agent into
Row is kneaded, and is formed by isostatic cool pressing technology, SiC reinforcement prefabricated component is made；By Vacuumgas pressure infiltration side
Method makes the melt containing aluminium and the SiC reinforcement prefabricated component that the silicon carbide aluminum-base composite structural member be made.
In order to solve the above technical problems, another technical solution that the application uses is: it is pre- to provide a kind of SiC reinforcement
The preparation method of product, which comprises the silicon-carbide particle of at least two different average particle sizes is provided；By predetermined ratio
The silicon-carbide particle of the difference average particle size is uniformly mixed；Bonding agent is added into silicon-carbide particle after mixing to carry out
It is kneaded, and is formed by isostatic cool pressing technology, the SiC reinforcement prefabricated component is made.
The beneficial effect of the application is: it is in contrast to the prior art, the application silicon carbide aluminum-base composite structural member
In preparation method, the silicon-carbide particle of at least two different average particle sizes is provided；By the different average particle sizes of predetermined ratio
Silicon-carbide particle be uniformly mixed；It adds bonding agent into silicon-carbide particle after mixing to be kneaded, and by cold etc.
Static pressure technology is formed, SiC reinforcement prefabricated component is made；By Vacuumgas pressure infiltration method, make melt containing aluminium and
The silicon carbide aluminum-base composite structural member is made in the SiC reinforcement prefabricated component.Due to selecting at least two varigrained carbon
Silicon carbide particle can fill mutually between particle and particle, so that silicon carbide prefabricated component obtains enough intensity；And by cold etc.
Static pressure technology is formed, and can obtain the structural member of big complicated shape, and mold is cheap, and obtained prefabricated component density is equal
Even, intensity is high；Vacuum pressed carries out liquid phase aluminising, the AlSiC structural member of available high intensity to SiC prefabricated component.
Detailed description of the invention
Fig. 1 is the flow chart of one embodiment of preparation method of the application silicon carbide aluminum-base composite structural member；
Fig. 2 is the flow chart of another embodiment of preparation method of the application silicon carbide aluminum-base composite structural member；
Fig. 3 is the flow chart of one embodiment of preparation method of the application SiC reinforcement prefabricated component.
Specific embodiment
Below in conjunction with the attached drawing in embodiment of the present invention, the technical solution in embodiment of the present invention is carried out clear
Chu is fully described by, it is clear that described embodiment is only some embodiments of the invention, rather than whole realities
Apply mode.Based on the embodiment in the present invention, those of ordinary skill in the art institute without making creative work
The every other embodiment obtained, belongs to the scope of protection of the invention.
Before the application is discussed in detail, the case where first introducing the prior art relevant to the application.
Automotive light weight technology is as the important means for reducing crude oil consumption and exhaust emissions, by extensive concern, studies have shown that
Automotive dead weight is every to reduce by 10%, can reduce oil consumption 6%~8%, reduces CO2Discharge 13%, and when automotive dead weight reduces, it rises
Walking accelerating ability can be more preferable, and braking distance when braking also can significantly shorten.Body of a motor car accounts for the 30%~60% of vehicle, automobile
About 70% fuel is consumption on body quality in operational process, so that vehicle body becomes the key of automotive light weight technology.In addition, vehicle
After body mitigates, the power consumption of the dynamical system of automobile can also be reduced, to advantageously reduce the size of engine and reduction gearbox, be realized
The further loss of weight of vehicle, therefore vehicle body loss of weight is very important for automotive light weight technology.
Vehicle mass reduction not simply mitigates vehicle weight, but in the premise for guaranteeing bus body strength and safety
Under, reduction body of a motor car quality as much as possible, while guarantee the manufacturing cost of body of a motor car in reasonable range, it is main at present
There are three types of means: (1) using lightweight mechanism, required with the strength and stiffness of bodywork parts as constraint, optimum design method is right
The mechanism of part optimizes；(2) lightweighting materials are used, by largely using lightweight, high-strength material to realize vehicle body
Substantially loss of weight；(3) use lightweight structure material, using made of Special Working Technology, with lightweight structure feature, vehicle
Use blank material；(4) more material mixing vehicle bodies are used, using high performance light material can effective lightweight vehicle body, but at
This still higher, considering cost and light weight effect, German scholar propose " more material lightweight structures ".Wherein, pass through
Automotive dead weight is reduced using lightweighting materials and has obtained the common concern of auto industry, becomes the mainstream skill of body lightening
Art mainly substitutes common iron using high strength steel plate, light metal material, composite material and uses more material mixing vehicle body knots
Structure.Wherein composite material is because density is low (1/3 or so of aluminium alloy), and specific strength height, impact resistance, Resisting fractre toughness be good, vibration damping
Sound insulation value is good, can design act charitably, be corrosion-resistant etc. it is a series of a little, obtained the attention of auto industry.Referring to table 1, table 1 is
Weight loss effect and relative cost comparison after light material substitution.
The weight loss effect of 1 light material of table substitution and relative cost comparison
High-performance light structural material occupies an important strategic position in economy and national defense construction, wherein as matrix
Lightweight structural material mainly has tri- kinds of alloys of A1, Mg, Ti, and reinforcement material mainly has SiC, A12O3、BC4、TiB2Deng.Mg alloy
Density ratio aluminium it is low, using its as matrix preparation composite material aerospace and auto industry application in have very big potentiality,
But its high-temperature stability is poor, is difficult to be used as critical component；Ti alloy-base composite material has good inoxidizability and high temperature
Mechanical property, but its preparation cost is high, processing difficulties, limits it and is widely used: and aluminium alloy quality is light, matrix alloy selection
The advantages that range is wide, high-strength, high-ductility, heat-resisting, anti-corrosion, and aluminium easily recycles, and can be recycled, and heat-treatability is good, so aluminium closes
Gold becomes a kind of widely applied basis material, becomes the mainstream of current such Materials and research work.Fine aluminium and aluminium close
Gold is used as parent metal, and alloy matrix aluminum mainly has Al-Cu-Mg, A1-Mg-Si and Al-Zn-Mg alloy.Reinforcement material
The intensity of middle SiC is high, hardness is high, thermal stability is good, price is relatively cheap, and relatively broad answer has been obtained in reinforcement material
With.
AlSiC composite material is widely used in aviation boat with its excellent thermophysical property and mechanical mechanics property at present
It, the fields such as Electronic Packaging, optical instrument, sports equipment.In auto industry field, it is mainly used in high performance brake at present
The high-temperature services such as piece, cylinder piston, bearing bush field, silicon-carbide particle hot conditions still modulus with higher and
Intensity so it is more preferable than primary aluminum alloy high-temp performance to be added to Aluminum Matrix Composites Strengthened by SiC, while being obviously improved zero
The specific strength and specific modulus of component, significantly reduce pts wt.
For AlSiC composite material, preparation SiC base prefabricated component is first had to, AlSiC Material cladding is then carried out.Existing skill
In art, AlSiC composite material is prepared, during SiC base prefabricated component, using powder injection molding technology, and powder is infused
When penetrating molding and preparing complex parts, it is desirable that injection powder has good mobility, needs to be added a large amount of organic binders, bonds
The subtractive process of agent is link most difficult in entire technique, and degreasing time is long, and the large quantity of exhaust gas that when degreasing generates makes environment
At pollution, while powder size is generally just suitble to powder injection molding process requirement in 0.5~20um, and injection moulding can only
The lesser device of size is made, for body of a motor car application and preparation, it is prefabricated that injection moulding method is unable to get the SiC met the requirements
Part.
In view of the above-mentioned problems, the silicon-carbide particle of the different average particle sizes of the application selection at least two, particle and particle it
Between can fill mutually so that silicon carbide prefabricated component obtains enough intensity；And formed by isostatic cool pressing technology, it can obtain
To the structural member of big complicated shape, and mold is cheap, obtained prefabricated component even density, and intensity is high；Vacuum pressed is to SiC
Prefabricated component carries out liquid phase aluminising, the AlSiC structural member of available high intensity.
The application is described in detail with embodiment with reference to the accompanying drawing.
It is the flow chart of one embodiment of preparation method of the application silicon carbide aluminum-base composite structural member referring to Fig. 1, Fig. 1,
This method comprises:
Step S101: the silicon-carbide particle of at least two different average particle sizes is provided.
Varigrained silicon-carbide particle, geometry is also different, and the geometry of usual silicon-carbide particle is irregular,
For Polyhedral, there are also very sharp wedge angles for some particles.SiC prefabricated component is prepared with a kind of SiC particulate of average particle size, is easy to make
It is imperfect at being filled between particle, cause prefabricated component intensity inadequate, finally makes the intensity of AlSiC composite material inadequate, it can not
As body structural member.Present embodiment selects the silicon-carbide particle of two or more different average particle sizes, so that different
It can be filled mutually between the SiC particulate and SiC particulate of size, so that SiC prefabricated component obtains enough intensity.
In one embodiment, the mean particle size range of silicon-carbide particle is 3~150um, such as: a kind of silicon-carbide particle
Average particle size be 3um, a kind of average particle size of silicon-carbide particle is 50um, and a kind of average particle size of silicon-carbide particle is
100um, a kind of average particle size of silicon-carbide particle are 150um, etc..In general, when grain graininess is smaller, grain spacing
Smaller, the intensity of composite material can improve；When grain graininess is larger, grain spacing is larger, and the plasticity of composite material can improve；
Therefore, in practical applications, two or more silicon-carbide particles is selected according to the intensity requirement of composite material and plasticity requirements etc.
Average particle size.
Step S102: the silicon-carbide particle of the different average particle sizes of predetermined ratio is uniformly mixed.
According to actual needs, it determines the predetermined ratio of the silicon-carbide particle of two or more different average particle sizes, then will
The silicon-carbide particle of the different average particle sizes of predetermined ratio is uniformly mixed.
Step S103: bonding agent is added into silicon-carbide particle after mixing and is kneaded, and passes through isostatic cool pressing
Technology is formed, SiC reinforcement prefabricated component is made.
Bonding agent is the substance referred to by homogeneous or heterogeneous surface bonding connection together, in present embodiment
In, bonding agent includes but is not limited to: and paraffin or base-material (such as: granularity is the silicon carbide and di-iron trioxide of 170~190 mesh
Mixture), auxiliary material (such as: granularity be 310~330 mesh Guangxi white clay) etc. composition, or including with paraffin it is main at
The binder divided, or commercial silicon carbide adhesive special, etc..
Bonding agent to be added into silicon-carbide particle after mixing to be kneaded, wherein the time of mixing is 4~12h,
Such as: 4h, 7h, 9h, 12h, etc..The time of mixing is different, and the intensity of obtained prefabricated component is also different, to final AlSiC
The intensity of composite structural member is also different, and according to actual application, the time of mixing is too short or too long, less properly.
In one embodiment, bonding agent is conventional use of paraffin, and paraffin is cheap, save the cost.Wherein, paraffin plus
Enter the 1%~5% of the total amount that amount is silicon-carbide particle after mixing, such as: 1%, 2%, 3%, 4%, 5%, etc..
Isostatic pressing technology be it is a kind of using product in closed pressure vessel it is each under impartial ultra high pressure state at
The ultrahigh-pressure hydraulic advanced technology of type.Isostatic cool pressing technology (Cold Isostatic Pressing, CIP) is at normal temperature, to lead to
Common rubber or plastics make thin wall wrap model material, using liquid as pressure medium, are mainly used for powder body material molding, further to burn
Knot, forging or hot isostatic pressing process provide green body.
Compared with conventional molding techniques, isostatic cool pressing technology is had the following characteristics that
The first, operating pressure is low；The second, molding extrudate density is high；Third, the even density of green compact are consistent.Equal static pressure
Fluid media (medium) transmits pressure, equal in all directions；Jacket is compressed unanimous on the whole with powder, and powder and jacket are without opposite fortune
Dynamic, the frictional resistance between them is seldom, and pressure only slightly declines, and therefore, blank density is uniform；4th, because
Even density, production draw ratio can be unrestricted, is conducive to produce rodlike, tubulose carefully long product；5th, it can not need
Lubricant is added in powder, has not only reduced the pollution to product, but also simplify manufacturing process；6th, product is had excellent performance, and is produced
Period is short, has a wide range of application.
In one embodiment, carrying out molding pressure by isostatic cool pressing technology is 50~200MPa, the mold used
For rubber mold.The forming technique is suitble to prepare the structural member of big complicated shape, and obtained prefabricated component even density is sintered out
The sample contraction consistency come is good, near-net-shape.Wherein, the size of rubber mold makes sintered SiC reinforcement prefabricated component
The size for being dimensioned slightly smaller than final products, be convenient for the subsequent processing of final products in this way, such as make sintered carbon
SiClx enhances each 0.1%-2% smaller than the size of final products to size of prefabricated component.
For the disadvantage for overcoming the limitation of dry powder molding compression machine, mold manufacture complicated, the application uses rubber mold, powder
The compression moulding of isostatic cool pressing mode is used after filling, rubber mold is not limited by shape of product complexity, and low in cost, and
Isostatic cool pressing makes SiC green body uniform force, and green density is uniform, and when sintering is not susceptible to deformation, while reinforcement may be implemented
Net molding.Therefore, on the whole, formed by isostatic cool pressing technology, the structural member of big complicated shape can be obtained, and
Mold is cheap, obtained prefabricated component even density, and intensity is high.
In conjunction with referring to fig. 2, if bonding agent uses paraffin, after step S103, it is also necessary to be pre-sintered, with degreasing, i.e.,
Further include:
Step S105: SiC reinforcement prefabricated component is pre-sintered.
Specifically, in one embodiment, the temperature being pre-sintered be 550~700 DEG C, soaking time be 0.5h~
4h.In this way, the paraffin of addition on the one hand can be excluded, the intensity of prefabricated component on the other hand can also be kept.
Step S104: by Vacuumgas pressure infiltration method, make melt and the SiC reinforcement prefabricated component containing aluminium that carbon be made
SiClx aluminum-base composite structural member.
Vacuumgas pressure infiltration technique is: prefabricated component first is made in reinforcement material, then prefabricated component is put into and is held positioned at pressure-bearing
In the mold of device, after extracting the gas in prefabricated component out, under vacuum and the collective effect of inert gas, metal is melted using pressure
Body is by being allowed to infiltrate prefabricated component in the press-in die of channel.Wherein, the preparation of prefabricated component and the control of technological parameter are that high property is made
The key of energy composite structural member.The advantages of this method, is: it is widely applicable, suitable for the preparation of a variety of composite materials, reinforcement
Type, shape, size, the volume fraction of material are substantially unrestricted；It can be directly prepared into composite part, it is especially complex-shaped
Part, substantially without following process；The defects of dipping carries out in a vacuum, Under Pressure Solidification, pore-free, loose, shrinkage cavity,
Dense structure, material property are good；Simple process, parameter is easy to control, can be according to the physics of reinforcement material and parent metal material
Chemical characteristic, strict temperature control, pressure and other parameters avoid serious interfacial reaction.
In one embodiment, by the aluminum alloy melting containing aluminium and after being heated to 720 DEG C~780 DEG C, 0.5~2h of constant temperature,
Degasification is removed slag, and aluminum alloy melting liquid is obtained；The SiC prefabricated component prepared (for example, SiC vehicle body prefabricated component) is placed in aluminising chamber,
Die cavity and SiC prefabricated component are vacuumized with die casting vacuum machine, the vacuum degree for keeping aluminising intracavitary is lower than 1000Pa, by aluminium alloy
Melt is passed through the infiltration of aluminising chamber, finally applies the pressure of 50~100MPa, enables aluminum alloy to melt and be infiltrated up in SiC prefabricated component
Hole in, keep pressure 2~4 minutes after, obtain AlSiC composite structural member (such as: what is be put into is SiC vehicle body prefabricated component, most
What is prepared afterwards is the automotive compounded body structure part of AlSiC).
In one embodiment, silicon carbide aluminum-base composite structural member is used for automotive body structure part.AlSiC composite structural member
Density it is low, substitute low carbon steel plate, can be with loss of weight nearly 2/3rds, while there is high specific strength and specific modulus, it is high-strength, high
Tough, wear-resisting, anti-corrosion, endurance etc., energy-saving and emission-reduction whiles, more enhance the security performance and service life of vehicle body.
It is the flow chart of one embodiment of preparation method of the application SiC reinforcement prefabricated component, the party referring to Fig. 3, Fig. 3
Method includes:
Step S201: the silicon-carbide particle of at least two different average particle sizes is provided.
Step S202: the silicon-carbide particle of the different average particle sizes of predetermined ratio is uniformly mixed.
Step S203: bonding agent is added into silicon-carbide particle after mixing and is kneaded, and passes through isostatic cool pressing
Technology is formed, SiC reinforcement prefabricated component is made.
Wherein, the mean particle size range of silicon-carbide particle is 3~150um.
Wherein, bonding agent is paraffin.
Wherein, the additional amount of paraffin is the 1%~5% of the total amount of silicon-carbide particle after mixing.
Wherein, it is 4~12h that the time that bonding agent is kneaded is added into silicon-carbide particle after mixing.
Wherein, carrying out molding pressure by isostatic cool pressing technology is 50~200MPa, and the mold used is rubber mold,
The size of the rubber mold makes the size for being dimensioned slightly smaller than final products of sintered SiC reinforcement prefabricated component, such as
So that sintered SiC reinforcement prefabricated component is each 0.1%-2% smaller than the size of final products to size.
The detailed description of related content refers to above method part, no longer superfluous herein to chat.
The silicon-carbide particle of the different average particle sizes of present embodiment selection at least two, can be mutual between particle and particle
Filling, so that silicon carbide prefabricated component obtains enough intensity；And formed by isostatic cool pressing technology, big complexity can be obtained
The structural member of shape, and mold is cheap, obtained prefabricated component even density, and intensity is high；It in this way, can be preparation
AlSiC composite structural member provides technical support.
Illustrate the preparation of silicon carbide aluminum-base composite structural member with specific embodiment below.
Embodiment 1:
The present embodiment illustrates so that AlSiC composite structural member prepares coachbuilt body B column as an example.
Traditional B column section shape is more complicated, is welded by more than one piece stamping steel plate, removes interior trim and overcoating part, B column one
As be divided into inner panel, stiffening plate, outside plate from inside to outside, substantially belong to closed thin wall girder construction, pass through welding manner with upper lower contact
B column and top cover curb girder and doorframe are attached.Guarantee that B column has enough intensity, or even needs to construct " outside plate-reinforcement
The tactic pattern of plate-local reinforcing plate-inner panel ", and stiffening plate structure is usually a small assembly, is pacified by installing on B column
Rigidity needed for the position of the full attachmentes such as band and door lock is larger, then needs to install corresponding stiffening plate, and excessive stiffening plate is not only not
Conducive to body lightening, and assembles vehicle body design and vehicle and complicate.
This example still uses inside and outside plate B-pillar structure, while the upper lower contact of B column is formed structure respectively inside and outside plate
Part is integrally formed in process of production, and is realized by following processing step.
(1) rubber mold designs: according to B column and the integrally formed planning of upper lower contact, net molding SiC reinforcement is prefabricated
It is slightly less than final products size, convenient final machining after part sintering.
(2) with mean particle size range be two kinds of SiC particulates of 4.0um and 30.0um, according to 1:1 ratio by SiC particulate,
3wt% paraffin (the 3% of the total amount of SiC particulate) is kneaded, and mixing time 4h obtains pelletizing.
(3) the resulting pelletizing of step 2 is filled to rubber mold, guarantees that powder packed is uniform, apparent density is consistent,
Isostatic cool pressing compression moulding is used under the pressure of 100MPa.
(4) the SiC green compact of step 3 are pre-sintered, 700 DEG C of sintering temperature, keep the temperature 4 hours, paraffin is vapored away, together
When obtain some strength porous structure SiC reinforcement prefabricated component.
(5) use 6063 aluminium alloys for aluminium based feedstock, constant temperature 1h, degasification are gone by aluminum alloy melting and after being heated to 750 DEG C
Slag obtains aluminum alloy melting liquid；The SiC prefabricated component is placed in aluminising chamber, with die casting vacuum machine to aluminising chamber and SiC prefabricated component into
Row vacuumizes, and the vacuum degree for keeping aluminising intracavitary is lower than 1000Pa, and opening molten aluminum channel makes molten aluminum fill up aluminising chamber, and is passed through nitrogen
Gas applies the pressure of 50MPa~100MPa, enables aluminum alloy in the hole that melt is infiltrated up in SiC prefabricated component, keeps pressure 2
After~4 minutes, the automotive compounded body structure part of AlSiC is obtained.Nitrogen herein can also select other inert gases to replace,
But selecting nitrogen, cost is relatively low.
(6) step 5 products obtained therefrom is further processed, by product design, it is only necessary to by the aluminium alloy part other than AlSiC
Removed by final size by machining.
Embodiment 2:
The present embodiment illustrates so that AlSiC composite structural member prepares coachbuilt body front longitudinal beam as an example.
In vehicle structure, it is widely adopted by the thin-wall member that low carbon steel plate is stamped to form, it can be by flange and its
His Member Welding together, main energy absorbing members when being vehicle collision, front longitudinal beam, body side wall, floor including automobile etc.
Perhaps position, traditional automobile front longitudinal beam cross section are thin-wall rectangular structures.Automobile occur head-on crash when, mainly by vehicle body before
The plastic deformation in portion absorbs impact kinetic energy, wherein what is played a major role is front longitudinal beam.
Compared to the low-carbon steel material of orthodox car front longitudinal beam, aluminium silicon carbide composite structural member has higher yield strength
And energy absorption ability, while achieving the purpose that significantly loss of weight.Comprehensively consider energy absorption ability, collision deceleration, displacement intrusion volume, and
It is convenient to rubber mold and fills out powder and compression moulding, this example selects rectangle and trapezium channel section automobile front longitudinal beam to be prepared, and by following
Processing step is realized.
(1) rubber mold designs: designing according to rectangle and trapezium channel section automobile front longitudinal beam, net molding SiC reinforcement prefabricated component is burnt
It is slightly less than final products size, convenient final machining after knot.
(2) it is tetra- kinds of SiC particulates of 4.0um, 16um, 30.0um, 70.0um, four kinds of particles according to 1:2:1 with average particle size:
1 be kneaded in the paraffin kneading machine of 3wt%, obtain pelletizing, mixing time 4h.
(3) the resulting pelletizing of step 2 is filled to rubber mold, guarantees that powder packed is uniform, apparent density is consistent,
Isostatic cool pressing compression moulding is used under the pressure of 150MPa.
(4) the SiC green compact of step 3 are pre-sintered, 700 DEG C of sintering temperature, keep the temperature 4 hours, paraffin is vapored away, together
When obtain some strength porous structure SiC reinforcement prefabricated component.
(5) use 6063 aluminium alloys for aluminium based feedstock, constant temperature 1h, degasification are gone by aluminum alloy melting and after being heated to 750 DEG C
Slag obtains aluminum alloy melting liquid；The SiC prefabricated component is placed in aluminising chamber, with die casting vacuum machine to aluminising chamber and SiC prefabricated component into
Row vacuumizes, and the vacuum degree for keeping aluminising intracavitary is lower than 1000Pa, and opening molten aluminum channel makes molten aluminum fill up aluminising chamber, and is passed through nitrogen
Gas applies the pressure of 50MPa~100MPa, enables aluminum alloy in the hole that melt is infiltrated up in SiC prefabricated component, keeps pressure 2
Minute~after 4 minutes, obtain the automotive compounded body structure part of AlSiC.Nitrogen herein can also select other inert gases
Instead of, but cost is relatively low for selection nitrogen.
(6) step 5 products obtained therefrom is further processed, by product design, it is only necessary to by the aluminium alloy part other than AlSiC
Removed by final size by machining.
Above-mentioned specific embodiment is silicon carbide aluminum-base composite structural member for automotive body structure part.AlSiC composite junction
The density of component is low, substitutes low carbon steel plate, can be with loss of weight nearly 2/3rds, while having high specific strength and specific modulus, high-strength,
High-ductility, wear-resisting, anti-corrosion, endurance etc., energy-saving and emission-reduction whiles, more enhance the security performance and service life of vehicle body.
Mode the above is only the implementation of the present invention is not intended to limit the scope of the invention, all to utilize this
Equivalent structure or equivalent flow shift made by description of the invention and accompanying drawing content, it is relevant to be applied directly or indirectly in other
Technical field similarly includes in scope of patent protection of the invention.
Claims (16)
1. a kind of preparation method of silicon carbide aluminum-base composite structural member, wherein the described method includes:
The silicon-carbide particle of at least two different average particle sizes is provided；
The silicon-carbide particle of the different average particle sizes of predetermined ratio is uniformly mixed；
Bonding agent is added into silicon-carbide particle after mixing to be kneaded, and is formed by isostatic cool pressing technology,
SiC reinforcement prefabricated component is made；
By Vacuumgas pressure infiltration method, make the melt containing aluminium and the SiC reinforcement prefabricated component that the carbonization sial be made
Matrix composite part.
2. preparation method according to claim 1, wherein the mean particle size range of the silicon-carbide particle be 3~
150um。
3. preparation method according to claim 1, wherein the bonding agent is paraffin.
4. preparation method according to claim 3, wherein the additional amount of the paraffin is the carbonization after mixing
The 1%~5% of the total amount of silicon particle.
5. preparation method according to claim 3, wherein it is described by Vacuumgas pressure infiltration method, make the fusing containing aluminium
Liquid and the SiC reinforcement prefabricated component are made before the silicon carbide aluminum matrix composite, comprising:
The SiC reinforcement prefabricated component is pre-sintered.
6. preparation method according to claim 5, wherein described to be pre-sintered to the SiC reinforcement prefabricated component
Temperature is 550~700 DEG C, and soaking time is 0.5h~4h.
7. preparation method according to claim 1, wherein described to add bonding into silicon-carbide particle after mixing
The time that agent is kneaded is 4~12h.
8. preparation method according to claim 1, wherein described to carry out molding pressure by isostatic cool pressing technology be 50
~200MPa, the mold used are rubber mold, and the size of the rubber mold makes sintered SiC reinforcement prefabricated component
The size for being dimensioned slightly smaller than final products.
9. preparation method according to claim 1, wherein it is described by Vacuumgas pressure infiltration method, make the fusing containing aluminium
The silicon carbide aluminum-base composite structural member is made in liquid and the SiC reinforcement prefabricated component, comprising:
The SiC reinforcement prefabricated component is placed in aluminising chamber, is evacuated to vacuum degree lower than 1000Pa；
Melt containing aluminium is passed through the aluminising chamber, and is filled with nitrogen or inert gas, air pressure is made to reach 50~100MPa, is protected
The time for holding the pressure is 2~4min, so that the melting liquid containing aluminium be made to be infiltrated up to the gap of the SiC reinforcement prefabricated component
In.
10. preparation method according to claim 1, wherein the silicon carbide aluminum-base composite structural member is used for body of a motor car
Structural member.
11. a kind of preparation method of SiC reinforcement prefabricated component, wherein the described method includes:
The silicon-carbide particle of at least two different average particle sizes is provided；
The silicon-carbide particle of the different average particle sizes of predetermined ratio is uniformly mixed；
Bonding agent is added into silicon-carbide particle after mixing to be kneaded, and is formed by isostatic cool pressing technology,
The SiC reinforcement prefabricated component is made.
12. preparation method according to claim 11, wherein the mean particle size range of the silicon-carbide particle be 3~
150um。
13. preparation method according to claim 11, wherein the bonding agent is paraffin.
14. preparation method according to claim 13, wherein the additional amount of the paraffin is the carbon after mixing
The 1%~5% of the total amount of silicon carbide particle.
15. preparation method according to claim 11, wherein described add into silicon-carbide particle after mixing is glued
Connecing the time that agent is kneaded is 4~12h.
16. preparation method according to claim 11, wherein described to be by the molding pressure of isostatic cool pressing technology progress
50~200MPa, the mold used are rubber mold, and the size of the rubber mold makes sintered SiC reinforcement prefabricated
The size for being dimensioned slightly smaller than final products of part.
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| PCT/CN2017/108066 WO2019080106A1 (en) | 2017-10-27 | 2017-10-27 | Aluminum silicon carbide-based composite structural member and method for preparing silicon carbide reinforced preform |
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| CN111138198A (en) * | 2019-12-30 | 2020-05-12 | 珠海凯利得新材料有限公司 | Preparation method and application of aluminum silicon carbide composite material |
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