阅读说明：本技术 一种耐高电流电机碳刷复合材料 (High-current-resistant motor carbon brush composite material ) 是由 白文进 于 2020-06-28 设计创作，主要内容包括：本发明涉及一种耐高电流电机碳刷复合材料,所述耐高电流电机碳刷复合材料按包括以下重量份的原料制造：碳粉40～55份,铜粉32～42份,二硫化钼3～4份,碳化钒3～4份,碳化铬1～5份。该碳刷复合材料有良好的耐磨性,在环境温度120℃,电流强度在25～28A条件下,平均磨损时间可达到1222h。(The invention relates to a high-current-resistant motor carbon brush composite material which is prepared from the following raw materials in parts by weight: 40-55 parts of carbon powder, 32-42 parts of copper powder, 3-4 parts of molybdenum disulfide, 3-4 parts of vanadium carbide and 1-5 parts of chromium carbide. The carbon brush composite material has good wear resistance, and the average wear time can reach 1222h under the conditions that the ambient temperature is 120 ℃ and the current intensity is 25-28A.)

1. The high-current-resistant motor carbon brush composite material is characterized by being prepared from the following raw materials in parts by weight: 40-55 parts of carbon powder, 32-42 parts of copper powder, 3-4 parts of molybdenum disulfide, 3-4 parts of vanadium carbide and 1-5 parts of chromium carbide.

2. The high current resistant motor carbon brush composite material of claim 1, wherein the high current resistant motor carbon brush composite material is prepared from the following raw materials in parts by weight: 55 parts of carbon powder, 35 parts of copper, 3 parts of molybdenum disulfide, 3 parts of vanadium carbide and 2 parts of chromium carbide.

3. The carbon brush composite material for the high current resistant motor according to claim 1, wherein the carbon powder is graphite powder.

4. The carbon brush composite material for the high-current-resistant motor according to claim 1, wherein the copper powder is electrolytic copper powder.

5. The high current resistant motor carbon brush composite of claim 1, prepared by the following method:

the method comprises the following steps: adding the carbon powder, the copper powder, the molybdenum disulfide, the vanadium carbide and the chromium carbide into a stirrer according to a proportion, stirring for 1-2 h, and uniformly mixing;

step two: putting the uniformly mixed raw materials into a raw material barrel of a pressure forming machine, pressing the powder into a blank material, wherein the pressing pressure is 20-30 MPa, and the pressure maintaining time is 3-5 s;

step three: uniformly placing the formed blank material in an industrial electric furnace to sinter into a carbon block, wherein the sintering conditions are as follows: firing for 5-8 h under the protection of argon at 850-900 ℃;

step four: the sintered carbon block is processed into the carbon brush strip.

6. A preparation method of a high current resistant motor carbon brush composite material according to any one of claims 1 to 5 is characterized by comprising the following steps:

the method comprises the following steps: adding the carbon powder, the copper powder, the molybdenum disulfide, the vanadium carbide and the chromium carbide into a stirrer according to a proportion, stirring for 1-2 h, and uniformly mixing;

step two: putting the uniformly mixed raw materials into a raw material barrel of a pressure forming machine, pressing the powder into a blank material, wherein the pressing pressure is 20-30 MPa, and the pressure maintaining time is 3-5 s;

step three: uniformly placing the formed blank material in an industrial electric furnace to sinter into a carbon block, wherein the sintering conditions are as follows: firing for 5-8 h under the protection of argon at 850-900 ℃;

step four: the sintered carbon block is processed into the carbon brush strip.

Technical Field

The invention relates to the field of new materials, in particular to a composite material for a carbon brush of a motor.

Background

Carbon brushes are important parts of a generator and are used for transmitting energy or signals between a fixed part and a rotating part (generally, a collecting ring) of the generator, and the carbon brushes continuously rub against the collecting ring during service, and are accompanied by electrical wear besides common mechanical friction wear. The traditional carbon brush has the phenomena of accelerated abrasion, serious arc ablation and the like under the condition of high current, the abrasion resistance is greatly weakened, the abrasion time is obviously shortened, and the service life is obviously shortened. Therefore, it is a necessary trend to improve the conventional carbon brush to develop a carbon brush material having still better wear resistance under high current conditions.

Disclosure of Invention

The invention provides a high-current-resistant motor carbon brush composite material aiming at the technical problems in the prior art.

The technical scheme for solving the technical problems is as follows: a high-current-resistant motor carbon brush composite material is prepared from the following raw materials in parts by weight: 40-55 parts of carbon powder, 32-42 parts of copper powder, 3-4 parts of molybdenum disulfide, 3-4 parts of vanadium carbide and 1-5 parts of chromium carbide.

Further, the health food is preferably prepared from the following raw materials in parts by weight: 55 parts of carbon powder, 35 parts of copper powder, 3 parts of molybdenum disulfide, 3 parts of vanadium carbide and 2 parts of chromium carbide.

Further, the carbon powder is graphite powder.

Further, the copper powder is electrolytic copper powder.

Further, the high-current-resistant motor carbon brush composite material is prepared by the following method:

the method comprises the following steps: adding the carbon powder, the copper powder, the molybdenum disulfide, the vanadium carbide and the chromium carbide into a stirrer according to a proportion, stirring for 1-2 h, and uniformly mixing;

step two: putting the uniformly mixed raw materials into a raw material barrel of a pressure forming machine, pressing the powder into a blank material, wherein the pressing pressure is 20-30 MPa, and the pressure maintaining time is 3-5 s;

step three: uniformly placing the formed blank material in an industrial electric furnace to sinter into a carbon block, wherein the sintering conditions are as follows: firing for 5-8 h under the protection of argon at 850-900 ℃;

step four: the sintered carbon block is processed into the carbon brush strip.

The invention also provides a preparation method of the high-current-resistant motor carbon brush composite material, which comprises the following steps:

the method comprises the following steps: adding the carbon powder, the copper powder, the molybdenum disulfide, the vanadium carbide and the chromium carbide into a stirrer according to a proportion and stirring for 1-2 h;

step two: the uniformly mixed raw materials are put into a raw material barrel of a pressure forming machine, a filling mechanism automatically adds powder into a die cavity, and the powder is pressed into a blank material, wherein the pressing pressure is 20 MPa-30 MPa, and the pressure maintaining time is 3 s-5 s;

step three: uniformly placing the formed blank material in an industrial electric furnace to sinter into a carbon block, wherein the sintering conditions are as follows: firing for 5-8 h under the protection of argon at 850-900 ℃;

step four: the sintered carbon block is processed into the carbon brush strip.

The invention has the beneficial effects that:

1. the carbon brush composite material has good wear resistance by adding the chromium carbide.

2. The molybdenum disulfide can generate a good synergistic effect with carbon, and the lubricating property of the carbon brush composite material is enhanced.

3. The vanadium carbide has some special properties, can improve the comprehensive mechanical properties of the material such as wear resistance, toughness, strength, thermal fatigue and the like, and can obviously improve the fracture toughness of the composite material and prolong the service life of the material by adding trace vanadium carbide.

4. The carbon brush composite material has the advantage that the average wear time can reach 1222h under the conditions that the ambient temperature is 120 ℃ and the current intensity is 25-28A.

Detailed Description

In the invention, the carbon powder is derived from natural graphite powder, the carbon content is more than or equal to 99 percent, and the granularity is less than 45 um;

the copper powder is derived from electrolytic copper powder, the purity is more than or equal to 99.5 percent, and the granularity<44.5um, loose packing ratio of 0.5-1.0g/cm³；

The molybdenum disulfide is gray powder, the purity is more than 98.0 percent, and the granularity is less than 44.5 um;

the purity of vanadium carbide is more than or equal to 99 percent, the average particle size is 50nm, and the loose packed ratio is 1.9-2.0g/cm³；

Chromium carbide is Cr₃C₂Purity is more than or equal to 99 percent, average granularity is 100nm, and loose packed ratio is 2.1-2.2g/cm³。

Preparing the following raw materials in parts by weight into a carbon brush composite material: 40-55 parts of carbon powder, 32-42 parts of copper powder, 3-4 parts of molybdenum disulfide, 3-4 parts of vanadium carbide and 1-5 parts of chromium carbide.

The high-current-resistant motor carbon brush composite material is prepared by the following method:

the method comprises the following steps: adding the carbon powder, the copper powder, the molybdenum disulfide, the vanadium carbide and the chromium carbide into a stirrer according to a proportion, stirring for 1-2 h, and uniformly mixing;

step two: putting the uniformly mixed raw materials into a raw material barrel of a pressure forming machine, pressing the powder into a blank material, wherein the pressing pressure is 20-30 MPa, and the pressure maintaining time is 3-5 s;

step three: uniformly placing the formed blank material in an industrial electric furnace to sinter into a carbon block, wherein the sintering conditions are as follows: firing for 5-8 h under the protection of argon at 850-900 ℃;

step four: the sintered carbon block is processed into the carbon brush strip.

The heating of the carbon brush is mainly related to factors such as current density, commutation sparks, heat dissipation conditions and mechanical friction born by the carbon brush, and if the current density, the commutation sparks and the heat dissipation conditions are the same, the electric conductivity of a carbon brush material can be improved by increasing the content of copper powder, so that the carbon brush can bear higher current density, but the higher the content of copper is, the higher the current density of the carbon brush is, the higher the calorific value of the carbon brush in the working process is, the higher the generated electric friction is, the larger the copper content can also cause the adhesion abrasion between the carbon brush and a copper commutator, the insufficient lubricity can also increase the mechanical friction, and the poorer the abrasion resistance of the carbon brush is. Through repeated research by the inventor, the heat productivity of the carbon brush is not obviously different when the carbon is 50-55 parts and the copper powder is 32-42 parts, and the carbon brush in the raw material composition range can bear the heat productivity. The wear resistance of the carbon brush is also related to the speed of forming an oxide film on the surface of the commutator, and if a uniform, moderate and stable oxide film can be quickly formed on the surface of the commutator, the wear of the carbon brush is small. When a certain amount of molybdenum disulfide is added, the forming speed of an oxide film on the surface of the commutator can be influenced, and the wear resistance of the carbon brush is greatly influenced. The vanadium carbide can improve the fracture toughness of the composite material and prolong the service life of the material. The chromium carbide is used as a wear-resistant material and is added into the carbon brush, so that the wear resistance of the carbon brush can be improved. However, the addition of these alloys is too much, which may affect the metallographic structure of carbon and copper, but is not favorable for improving the wear resistance of the carbon brush under high current density. Therefore, when 55 parts of carbon powder, 35 parts of copper powder, 3 parts of molybdenum disulfide, 3 parts of vanadium carbide and 2 parts of chromium carbide are needed, the components are matched with the preparation method according to the proportion, and the optimal synergistic effect can be generated among the components to obtain the optimal performance.