CN114438363A - Production method of directly-formed foam copper carbon matrix composite material electric boot - Google Patents

Abstract

The invention relates to the technical field of rail transit, and discloses a production method of a directly-formed copper foam carbon matrix composite material electric boot, which comprises the following steps: s1, adopting 15ppi foam copper with the porosity of 95%; s2, performing vacuum impregnation on the foam copper by using phenolic resin at 90 ℃ under the vacuum of 1.0 MPa; s3, curing: curing at room temperature of-40 ℃ for 1h, curing at 40-80 ℃ for 3h, curing at 80-100 ℃ for 2h, curing at 100-120 ℃ for 2h, curing at 120-130 ℃ for 2h, then preserving heat at 130 ℃ for 1h, naturally cooling and taking the material; the performance of the foam copper-carbon/carbon composite material is superior to that of a pure carbon material, and because of the three-dimensional net structure, the foam copper-carbon/carbon composite material can bear a large amount of energy when in impact, and can play a role in drawing and pinning to prevent crack propagation; meanwhile, the foam copper-carbon/carbon composite material also has excellent friction and wear properties.

Description

Production method of directly-formed copper foam carbon matrix composite material electric shoe

Technical Field

The invention relates to the technical field of rail transit, in particular to a method for producing a directly-formed copper foam carbon matrix composite electric boot.

Background

Along with the rapid development of rail transit, the railway department has more and more demand on pantograph slide plates, and most of the pantograph slide plates in China depend on import. How to realize the localization of the pantograph slide plate becomes a problem to be solved urgently at present. As a current collecting material for rail transit, when a train runs at a high speed, the pantograph slide plate not only can transmit electric power from a conductive net to the train, but also can be a typical friction material. Therefore, in order to ensure the stable and safe operation of the train, the physical performance of the pantograph slide plate is highly required. The domestic carbon sliding plate is far short of meeting the use requirements in terms of breaking resistance and strength. The most critical part of the production process is that no mature forming equipment exists, when most manufacturers rely on an improved extruder to produce the electric shoes, not only is the theoretical verification of a die nozzle curve and an extrusion force not carried out, but also a large number of pores exist in the extruded pure carbon electric shoes.

At present, the problem of insufficient physical performance of the pure carbon electric shoe is solved. In the publication CN201911153808.2, a method for preparing a carbon fiber reinforced pantograph pure carbon slip strip material is disclosed, in which a non-metallic conductive material, carbon fiber reinforced and modified coal pitch, is used as a conductive medium of the material, so that the conductivity is improved; the carbon slide bar material prepared by carbon fiber reinforcement has stable structure, strong physical and chemical properties and good safety performance; the resistivity, the mechanical strength and the like of the pure carbon sliding plate material are enhanced; the material prepared by the process is simple, is beneficial to mass production, adopts the raw material with wide market and has low cost; the carbon slide bar material prepared by the invention completely meets or is superior to technical conditions of a pantograph carbon slide plate of an alternating current transmission locomotive, resists large power frequency and impact current impact, and has stable resistance; corrosion resistance, no toxicity, environmental protection, long service life and low cost.

However, the non-wettability of the carbon fiber and the carbon matrix composite is an unchangeable technical difficulty, and the carbon fiber is relatively difficult to disperse and agglomerate, but the publication does not mention how to disperse the carbon fiber. In addition, the carbon fiber having a high elastic modulus releases a large amount of internal stress during baking after molding, which causes a wall gap to be formed at a contact surface between the carbon fiber and the carbon substrate, and thus the crack is easily propagated.

In publication CN201510018265.9, a method for vacuum pressure infiltration of a pantograph metal-impregnated carbon sliding plate is disclosed, comprising the steps of: firstly, placing a porous carbon strip in a first graphite boat; secondly, the copper matrix is copper alloy, the additive elements are Cr or Ti, and the copper alloy block is placed in a second graphite boat; thirdly, vacuumizing a system where the graphite boat is positioned, and starting heating after a set vacuum degree is reached; after the temperature is raised to a set temperature, the furnace body is rotated to pour the copper alloy into the first graphite boat where the porous carbon strips are positioned, and the pressure is rapidly pressurized to finish the pressure infiltration process; fourthly, after cooling, rotating the furnace body, and pouring the redundant copper alloy back to the second graphite boat; and taking out the metal-impregnated carbon sliding plate.

However, the casting is carried out by rotating the furnace body, and the method is not only dangerous but also uncontrollable under high temperature and high pressure. The dipping copper alloy not only needs to heat and melt the alloy, but also needs to apply larger pressure to promote the copper alloy to enter the carbon matrix, the pressure even needs more than 500MPa, and simultaneously, the furnace body is also rotated in the technical scheme, which cannot be realized in actual production at all, and cannot meet continuous industrial production, so the method has high danger and difficult realizability. Moreover, even at a temperature of 1000 ℃, the wetting angle of the molten copper alloy with carbon is as high as 140 degrees, which is not only unsatisfactory for impregnating open pores, but also insufficient for impregnating closed pores.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a method for producing a directly-formed copper foam carbon matrix composite material electric shoe, which solves the problems in the background technology.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: a method for producing a directly-formed copper foam carbon matrix composite material electric boot comprises the following steps:

s1, adopting 15ppi foam copper with the porosity of 95%;

s2, performing vacuum impregnation on the foam copper by using phenolic resin at 90 ℃ under the vacuum of 1.0 MPa;

s3, curing: curing at room temperature of-40 ℃ for 1h, curing at 40-80 ℃ for 3h, curing at 80-100 ℃ for 2h, curing at 100-120 ℃ for 2h, curing at 120-130 ℃ for 2h, then preserving heat at 130 ℃ for 1h, naturally cooling and taking the material;

s4, carbonization: carbonizing at room temperature of-100 deg.C for 2h, carbonizing at 100-350 deg.C for 10h, carbonizing at 350-500 deg.C for 10h, and carbonizing at 500-800 deg.C for 5 h;

s5, uniformly mixing graphite, micron-sized carbon black, pitch coke, stearic acid and iron oxide, kneading and coating, wherein the kneading and coating temperature depends on the softening point of the binder pitch at 120 ℃, the kneading and coating time is 100min, and then crushing into 100-mesh powder;

s6, sequentially placing 100-mesh powder, carbon deposition foam copper and 100-mesh powder from top to bottom, heating to 180 ℃, prepressing for 5min under the pressure of 5MPa, pressing under the pressure of 30MPa, and maintaining the pressure for 20min to obtain a finished product.

Preferably, in step S2, the phenolic resin used is diluted with a diluent, and the ratio of the phenolic resin to the diluent is 100: 20.

Preferably, the specific process of step S2 is as follows:

early preparation: cleaning the surface of a workpiece by using an air gun; the phenolic resin viscosity was 200mPa · s, the viscosity when heated for use was 150mPa · s;

dipping: preheating a workpiece for 1h in a preheating box at 150 ℃, preheating phenolic aldehyde to 50 ℃ and preheating for 0.5h, and cooling the impregnation tank to 45 ℃ after preheating the impregnation tank to 50 ℃; then putting the workpiece into a dipping tank, vacuumizing to-0.1 MPa for 1.5h, wherein the vacuum pump continuously works in the process, and the dipping tank keeps the heating temperature of 45 ℃; under the condition that the vacuum pump is not closed, opening a special resin suction valve, sucking the preheated resin, and continuously vacuumizing for 1 h; then the vacuumized valve is closed, the inflation valve is opened, the positive pressure is 0.65MPa and lasts for 1 hour, and the pressure is maintained for 0.5 hour under the condition of the air pressure of the air source.

Preferably, in step S5, the graphite is 200 meshes, and the pitch coke is 80-300 meshes.

(III) advantageous effects

The invention provides a production method of a directly-formed copper foam carbon matrix composite material electric shoe, which has the following beneficial effects:

the performance of the foam copper-carbon/carbon composite material is superior to that of a pure carbon material, and because of the three-dimensional net structure, the foam copper-carbon/carbon composite material can bear a large amount of energy when in impact, and can play a role in drawing and pinning to prevent crack propagation; meanwhile, the copper foam-carbon/carbon composite material has excellent friction and wear properties, not only plays a role of a conductive network to stably transit current to a rail train, but also can enter pores of a carbon matrix to play a role of reinforcing the matrix when copper in a large plastic deformation and a certain molten state is subjected to high-temperature friction, so that the friction properties are excellent.

Drawings

FIG. 1 is a schematic process flow diagram of the present invention;

FIG. 2 is a schematic view of the pressing of the composite material of the present invention;

FIG. 3 is a partially enlarged schematic view of the composite material of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1-3, the present invention provides a technical solution: a method for producing a directly-formed copper foam carbon matrix composite material electric boot comprises the following steps:

s1, adopting 15ppi foam copper with the porosity of 95%;

s2, performing vacuum impregnation on the copper foam by using phenolic resin at 90 ℃ under the vacuum of 1.0MPa, wherein the phenolic resin is diluted by a diluent, the ratio of the phenolic resin to the diluent is 100: 20, and the specific impregnation process comprises the following steps:

early preparation: cleaning the surface of a workpiece by using an air gun; the phenolic resin viscosity was 200mPa · s, the viscosity when heated for use was 150mPa · s;

dipping: preheating a workpiece for 1h in a preheating box at 150 ℃, preheating phenolic aldehyde to 50 ℃ and preheating for 0.5h, and cooling the impregnation tank to 45 ℃ after preheating the impregnation tank to 50 ℃; then putting the workpiece into a dipping tank, vacuumizing to-0.1 MPa for 1.5h, continuously operating the vacuum pump in the process, and keeping the heating temperature of the dipping tank at 45 ℃; under the condition that the vacuum pump is not closed, opening a special resin suction valve, sucking the preheated resin, and continuously vacuumizing for 1 h; then closing the vacuumizing valve, opening the inflation valve, keeping the positive pressure of 0.65MPa for 1h, and maintaining the pressure for 0.5h under the condition of air source pressure;

s3, curing: curing at room temperature of-40 ℃ for 1h, curing at 40-80 ℃ for 3h, curing at 80-100 ℃ for 2h, curing at 100-120 ℃ for 2h, curing at 120-130 ℃ for 2h, then preserving heat at 130 ℃ for 1h, naturally cooling and taking the material;

s4, carbonization: carbonizing at room temperature of-100 deg.C for 2h, carbonizing at 100-350 deg.C for 10h, carbonizing at 350-500 deg.C for 10h, and carbonizing at 500-800 deg.C for 5 h;

s5, uniformly mixing 200-mesh graphite, micron-sized carbon black, 80-300-mesh asphalt coke, stearic acid and iron oxide, kneading and coating, wherein the kneading and coating temperature depends on the softening point of the adhesive asphalt at 120 ℃, the kneading and coating time is 100min, and then crushing into 100-mesh powder;

s6, sequentially placing 100-mesh powder, carbon deposition foamy copper and 100-mesh powder from top to bottom, heating to 180 ℃, prepressing for 5min under the pressure of 5MPa, pressing under the pressure of 30MPa, and maintaining the pressure for 20min to obtain a finished product, wherein the comparison result of the finished product and the pure carbon is as follows:

it is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (4)

1. A production method of a directly-formed copper foam carbon matrix composite material electric boot is characterized by comprising the following steps: the method comprises the following steps:

s1, adopting 15ppi foam copper with the porosity of 95%;

s2, performing vacuum impregnation on the foam copper by using phenolic resin at 90 ℃ under the vacuum of 1.0 MPa;

s3, curing: curing at 40 ℃ for 1h, curing at 40-80 ℃ for 3h, curing at 80-100 ℃ for 2h, curing at 100-120 ℃ for 2h, curing at 120-130 ℃ for 2h, then preserving heat at 130 ℃ for 1h, naturally cooling and taking materials;

s4, carbonization: carbonizing at room temperature of-100 deg.C for 2h, carbonizing at 100-350 deg.C for 10h, carbonizing at 350-500 deg.C for 10h, and carbonizing at 500-800 deg.C for 5 h;

s5, uniformly mixing graphite, micron-sized carbon black, pitch coke, stearic acid and iron oxide, kneading and coating, wherein the kneading and coating temperature depends on the softening point of the binder pitch at 120 ℃, the kneading time is 100min, and then crushing into 100-mesh powder;

s6, sequentially placing 100-mesh powder, carbon deposition foam copper and 100-mesh powder from top to bottom, heating to 180 ℃, prepressing for 5min under the pressure of 5MPa, pressing under the pressure of 30MPa, and maintaining the pressure for 20min to obtain a finished product.

2. The method for producing a directly formed copper foam carbon matrix composite electric shoe as claimed in claim 1, wherein: in step S2, the phenolic resin used is diluted with a diluent, and the ratio of the phenolic resin to the diluent is 100: 20.

3. The method for producing a directly formed copper foam carbon matrix composite electric shoe as claimed in claim 1, wherein: the specific process of step S2 is as follows:

early preparation: cleaning the surface of a workpiece by using an air gun; the phenolic resin viscosity was 200mPa · s, the viscosity when heated for use was 150mPa · s;

dipping: preheating a workpiece for 1h in a preheating box at 150 ℃, preheating phenolic aldehyde to 50 ℃ and preheating for 0.5h, and cooling the impregnation tank to 45 ℃ after preheating the impregnation tank to 50 ℃; then putting the workpiece into a dipping tank, vacuumizing to-0.1 MPa for 1.5h, wherein the vacuum pump continuously works in the process, and the dipping tank keeps the heating temperature of 45 ℃; under the condition that the vacuum pump is not closed, opening a special resin suction valve, sucking the preheated resin, and continuously vacuumizing for 1 h; then the vacuumized valve is closed, the inflation valve is opened, the positive pressure is 0.65MPa and lasts for 1 hour, and the pressure is maintained for 0.5 hour under the condition of the air pressure of the air source.

4. The method for producing a directly formed copper foam carbon matrix composite electric shoe as claimed in claim 1, wherein: in the step S5, the graphite is 200 meshes, and the pitch coke is 80-300 meshes.

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