Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification.
A method for preparing a carbon/carbon composite material pantograph slider for a high-speed train comprises the following steps:
1) graphitizing the carbon fiber pantograph slider preform;
2) charging, namely sequentially charging a plurality of carbon fiber pantograph slider preforms subjected to graphitization treatment into a charging barrel tool;
3) purging;
4) starting a cooling water circulation system;
5) heating;
6) fast deposition, introducing carbon source gas from the top or the bottom of the high-temperature vapor deposition furnace, preheating the gas, introducing the preheated gas through a narrow gap between the charging barrel tool and the preform, enabling the preheated gas to flow through the narrow gap between each layer of preform surface, and enabling tail gas to pass through the narrow gapThe tail end of the charging barrel tool is collected and drawn out of the furnace body, wherein the flow of the carbon source gas is controlled to be 5m3/h~50m3The pressure is controlled to be 3 kPa-50 kPa, the central temperature of a constant temperature area is controlled to be 800-1100 ℃, and the deposition time is controlled to be 150-250 h; the graphitization treatment temperature in the step 7) is 2200-2600 ℃, and the treatment time is 2-5 h;
7) carrying out graphitization treatment;
8) and (4) machining, namely finely machining and polishing the graphitized carbon/carbon composite material pantograph slide block according to the final structural design, and finishing the preparation of the carbon/carbon composite material pantograph slide block.
Wherein the graphitization temperature in the step 1) is 2200-2500 ℃, and the graphitization treatment time is 2-10 h; the charging barrel tool is a porous straight barrel of a graphite or carbon/carbon composite material product; the purging time in the step 3) lasts for 1-5 h; in the step 5), the temperature rising speed is controlled to be 50-150 ℃/h, and the temperature is kept when the temperature reaches 800-1100 ℃; in the step 6), the carbon source gas is natural gas, methane, ethane, ethylene, propane or propylene.
Example 1
A method for preparing a carbon/carbon composite material pantograph slider for a high-speed train comprises the following steps:
1) graphitizing the carbon fiber pantograph slider preform, wherein the graphitizing temperature is 2200 ℃, and the graphitizing time is 2 h;
2) and (4) charging, namely filling the prefabricated body of the needled laminated pantograph slide block in a grid shape in the furnace body of the high-temperature vapor deposition furnace. Fig. 1 is a schematic view of a pantograph slider preform charging tool, fig. 2 is a schematic view of a pantograph slider preform charging tool from top, the charging barrel tool is a porous straight barrel of a graphite/carbon composite material product, fig. 3 is a schematic view of a partial enlarged view of a single charging unit tool from top, two sides of each block, namely each row of needled lamination pantograph slider preforms, are gas flow areas, a in fig. 3 is a preform area, the width of the gas flow area B is 2mm, in the figure, the part of the two sides in the furnace body, which exceeds the gas flow area B, is a limiting area, and is used for fixing the position of the preforms in the tool, and the later machining is used for processing, and the tool layout is reasonable as shown by simulating and analyzing the flow field distribution of a gas precursor in a narrow slit;
3) purging, namely purging the whole high-temperature vapor deposition furnace by using high-purity Ar, wherein the purging time lasts for 1 h;
4) starting a cooling water circulation system;
5) heating, wherein the heating speed is controlled at 50 ℃/h, and the heating is stopped when the temperature reaches 800 ℃;
6) performing rapid deposition, introducing natural gas as carbon source gas from the top of the high temperature vapor deposition furnace, and controlling the flow at 5m3Controlling the pressure at 3kPa, wherein a carbon source gas firstly passes through a preheating area of a furnace top gas channel, the preheating area is divided by a graphite carbon plate, the purpose is to finally heat the temperature of the mixed gas to 950 ℃, and then the mixed gas enters a constant temperature area of a preform area, and the deposition time is controlled at 100 h;
7) performing graphitization treatment, namely putting the sample in a high-temperature furnace for graphitization treatment, wherein the graphitization treatment temperature is 2200 ℃, and the treatment time is 2 hours;
8) and (4) machining, namely machining the graphitized product according to the product requirement to form a final product.
Example 2
A method for preparing a carbon/carbon composite material pantograph slider for a high-speed train comprises the following steps:
1) graphitizing the carbon fiber pantograph slider preform, wherein the graphitizing temperature is 2500 ℃, and the graphitizing time is 10 hours;
2) loading, namely filling the needled laminated pantograph slider preforms in a grid shape in a furnace body of a high-temperature vapor deposition furnace, wherein each block, namely two sides of each row of needled laminated pantograph slider preforms are gas flow areas, the width of each gas flow area is 15mm, the parts of the two sides in the furnace body, which exceed the gas flow areas, are limiting areas, and the positioning of the preforms in the tool is fixed, and the subsequent machining is carried out;
3) purging with high purity N2Purging the whole high-temperature vapor deposition furnace for 5 hours;
4) starting a cooling water circulation system;
5) heating, wherein the heating speed is controlled at 150 ℃/h, and the heating is stopped when the temperature reaches 1100 ℃;
6) performing rapid deposition, introducing methane as carbon source gas from the bottom of the high temperature vapor deposition furnace, and controlling the flow at 50m3Controlling the pressure at 50kPa, firstly passing a carbon source gas through a preheating area of a gas channel at the bottom of a furnace, dividing the preheating area by a graphite carbon plate, and finally heating the temperature of the mixed gas to 1100 ℃ and then entering a constant temperature area of a preform area, wherein the deposition time is controlled at 400 h;
7) performing graphitization treatment, namely putting the sample in a high-temperature furnace for graphitization treatment, wherein the graphitization treatment temperature is 2600 ℃, and the treatment time is 5 h;
8) and (4) machining, namely machining the graphitized product according to the product requirement to form a final product.
Example 3
A method for preparing a carbon/carbon composite material pantograph slider for a high-speed train comprises the following steps:
1) graphitizing the carbon fiber pantograph slider preform, wherein the graphitizing temperature is 2300 ℃, and the graphitizing time is 8 h;
2) loading, namely filling the needled laminated pantograph slider preforms in a grid shape in a furnace body of a high-temperature vapor deposition furnace, wherein each block, namely two sides of each row of needled laminated pantograph slider preforms are gas flow areas, the width of each gas flow area is 10mm, the parts of the two sides in the furnace body, which exceed the gas flow areas, are limiting areas, and the positioning of the preforms in the tool is fixed, and the subsequent machining is carried out;
3) purging, namely purging the whole high-temperature vapor deposition furnace by using high-purity Ar, wherein the purging time lasts for 2 h;
4) starting a cooling water circulation system;
5) heating, wherein the heating speed is controlled at 80 ℃/h, and the heating is stopped when the temperature reaches 1000 ℃;
6) fast deposition, propane is taken as carbon source gas and is introduced from the top of the high-temperature vapor deposition furnace to flowThe amount is controlled to be 20m3Controlling the pressure at 20kPa, wherein a carbon source gas firstly passes through a preheating area of a furnace top gas channel, the preheating area is divided by a graphite carbon plate, the purpose is to finally heat the temperature of the mixed gas to 960 ℃, and then the mixed gas enters a constant temperature area of a preform area, and the deposition time is controlled at 200 h;
7) performing graphitization treatment, namely putting the sample in a high-temperature furnace for graphitization treatment, wherein the graphitization treatment temperature is 2300 ℃, and the treatment time is 3 hours;
8) and (4) machining, namely machining the graphitized product according to the product requirement to form a final product.
Example 4
A method for preparing a carbon/carbon composite material pantograph slider for a high-speed train comprises the following steps:
1) graphitizing the carbon fiber pantograph slider preform, wherein the graphitizing temperature is 2500 ℃, and the graphitizing time is 5 hours;
2) loading, namely filling the needled laminated pantograph slider preforms in a grid shape in a furnace body of a high-temperature vapor deposition furnace, wherein each block, namely two sides of each row of needled laminated pantograph slider preforms are gas flow areas, the width of each gas flow area is 6mm, the parts of the two sides in the furnace body, which exceed the gas flow areas, are limiting areas, and the positioning of the preforms in the tool is fixed, and the subsequent machining is carried out;
3) purging with high purity N2Purging the whole high-temperature vapor deposition furnace for 3 hours;
4) starting a cooling water circulation system;
5) heating, wherein the heating speed is controlled at 80 ℃/h, and the heating is stopped when the temperature reaches 990 ℃;
6) performing rapid deposition, introducing propylene as carbon source gas from the bottom of the high temperature vapor deposition furnace, and controlling the flow at 30m3H, controlling the pressure at 10kPa, passing the carbon source gas through a preheating zone of a furnace bottom gas channel, dividing the preheating zone by a graphite carbon plate, finally heating the temperature of the mixed gas to 1100 ℃, then entering a constant temperature zone of a preform area, and controlling the deposition timeAt 100 h;
7) performing graphitization treatment, namely putting the sample in a high-temperature furnace for graphitization treatment, wherein the graphitization treatment temperature is 2500 ℃, and the treatment time is 3 hours;
8) and (4) machining, namely machining the graphitized product according to the product requirement to form a final product.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.