A high-strength automobile brake disc and preparation method thereof

Abstract

The present invention relates to the technical field of automobile brake disc preparation, and specifically to a high-strength automobile brake disc and a preparation method thereof. The preparation method of the high-strength automobile brake disc provided by the present invention comprises the following steps: electroplating an aluminum film layer on the surface of the brake disc substrate; mixing zirconium propionate, titanium sulfate, ferrocene dicarboxylic acid, glacial acetic acid and a solvent, and then performing a hydrothermal reaction to obtain a spray coating; using the spray coating to form a wear-resistant coating on the aluminum film surface of the brake disc substrate by a plasma spraying process; heat-treating, electrolyzing, and performing a secondary heat treatment on the wear-resistant coating of the brake disc substrate to obtain the high-strength automobile brake disc. The wear-resistant coating obtained by the process of the present invention not only has high strength, but also has good bonding between the coating and the substrate and good wear resistance.

Description

Technical Field

[0001] The invention relates to the technical field of automobile brake disc preparation, and in particular to a high-strength automobile brake disc and a preparation method thereof. Background Art

[0002] With the improvement of people's living standards, cars have become an indispensable means of transportation for people, but they also bring problems such as air pollution. In order to effectively alleviate the energy and pollution problems brought by cars, achieving lightweight cars has become an important measure.

[0003] At present, most automobile brake disc materials are cast iron materials. However, cast iron materials have a high specific gravity, which leads to a large weight of the car and high energy consumption. In order to achieve lightweight automobiles, lightweight materials such as aluminum-based materials are generally used to replace heavier cast iron materials. However, aluminum-based materials as brake disc materials have low strength and poor wear resistance. In order to improve the strength and wear resistance of aluminum-based brake discs, the existing technology generally covers the surface of the aluminum-based brake disc with a wear-resistant layer, but the improvement in strength and wear resistance is still limited. Summary of the invention

[0004] In order to overcome the defect that the wear-resistant layer on the surface of the existing aluminum-based brake disc has limited improvement on the strength and wear resistance of the brake disc, a high-strength automobile brake disc and a preparation method thereof are provided.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme:

[0006] A method for preparing a high-strength automobile brake disc comprises the following steps:

[0007] 1) electroplating an aluminum film layer on the surface of a brake disc substrate to obtain a brake disc substrate coated with an aluminum film;

[0008] 2) mixing zirconium propionate, titanium sulfate, ferrocene dicarboxylic acid, glacial acetic acid and a solvent, and then subjecting the mixture to a hydrothermal reaction. After the reaction is completed, centrifuging, washing and drying the mixture to obtain a spray coating;

[0009] 3) using a plasma spraying process to form a wear-resistant coating on the aluminum film surface of the brake disc substrate;

[0010] 4) heat treating the wear-resistant coating of the brake disc substrate to obtain a heat-treated brake disc substrate;

[0011] 5) immersing the aluminum film layer and the wear-resistant coating of the brake disc substrate in an acid electrolyte for electrolysis, and after the electrolysis is completed, taking out the brake disc substrate, washing it with water, and drying it to obtain an electrolyzed brake disc substrate;

[0012] 6) The wear-resistant coating of the brake disc substrate after electrolysis is subjected to secondary heat treatment to obtain the high-strength automobile brake disc.

[0013] Preferably, in step 2), the mass ratio of zirconium propionate, titanium sulfate, ferrocenedicarboxylic acid and glacial acetic acid is (8-15): (8-15): (5-10): (20-50).

[0014] Preferably, the thickness of the aluminum film layer is 10-20 μm.

[0015] Preferably, the mass ratio of the glacial acetic acid to the solvent is (0.2-1):1;

[0016] The hydrothermal reaction temperature is 100-140° C., and the hydrothermal reaction time is 8-15 hours.

[0017] Preferably, the solvent in step 2) is dichloromethane;

[0018] The washing step is performed using dichloromethane.

[0019] Preferably, the thickness of the wear-resistant coating in step 3) is 500-700 μm;

[0020] In the plasma spraying process, the spraying current is 300-350A, the spraying voltage is 40V, the powder feeding rate is 3.5-4.0g / min, the argon flow rate is 120-130SCFH, the hydrogen flow rate is 20-25SCFH, the powder feeding direction is 90°, the spraying distance is 500-600mm, and the spraying speed is 20-30mm / s.

[0021] Preferably, in step 4), the heat treatment temperature is 580-640° C. and the heat treatment time is 1-3 h;

[0022] Step 5) the solutes in the neutral-acid electrolyte are sulfuric acid and sodium chloride, wherein the concentration of sulfuric acid is 5-15 g / L, and the concentration of sodium chloride is 25-35 g / L;

[0023] The current density in the electrolysis step is 0.02-0.04A·cm -2 , the electrolysis time is 20-40min.

[0024] Preferably, in step 6), the secondary heat treatment temperature is 460-520° C., and the secondary heat treatment time is 1-3 h.

[0025] Preferably,

[0026] Before electroplating the aluminum film layer on the surface of the brake disc substrate in step 1), the step also includes grinding and sandblasting the surface of the brake disc substrate;

[0027] The brake disc substrate is an aluminum alloy brake disc substrate; the aluminum alloy brake disc substrate, calculated by mass fraction, includes the following components: Si 6.2-6.9%, Mg 0.3-0.4%, Fe 0.2-0.3%, Cu 0.1-0.2%, and the balance is Al.

[0028] The present invention also provides a method for preparing a high-strength automobile brake disc, which is prepared by the above-mentioned preparation method.

[0029] Beneficial effects of the present invention:

[0030] The invention provides a method for preparing a high-strength automobile brake disc. First, an aluminum film is formed on the surface of a brake disc substrate. A spray coating obtained by a specific method is used to form a wear-resistant coating on the surface of the aluminum film of the brake disc substrate by a plasma spraying process. Then, the high-strength automobile brake disc is obtained by a primary heat treatment, electrolysis and secondary heat treatment. The invention forms a cross-linked network structure by the coordination of ferrocene dicarboxylic acid with metal zirconium and metal titanium through a hydrothermal reaction. The metal zirconium, metal titanium and ferrocene are evenly distributed in the network structure. Then, a wear-resistant coating is formed on the surface of the aluminum film by a plasma spraying process. Through the first heat treatment, the metal zirconium and metal titanium form corresponding oxides. At the same time, the ferrocene connected thereto evaporates to form pores in the wear-resistant coating. Then, through electrolysis treatment, aluminum ions in the aluminum film migrate into the pores and form aluminum oxide through a secondary heat treatment. The wear-resistant coating obtained by the process of the invention has not only high strength, but also good bonding between the coating and the substrate and good wear resistance. DETAILED DESCRIPTION

[0031] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0032] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0033] Example 1

[0034] This embodiment provides a method for preparing a high-strength automobile brake disc, comprising the following steps:

[0035] 1) grinding and sandblasting the surface of a cast aluminum alloy brake disc substrate to obtain a pretreated brake disc substrate, wherein the aluminum alloy brake disc substrate comprises the following components by mass fraction: Si 6.8%, Mg 0.4%, Fe 0.3%, Cu 0.2%, and the balance Al;

[0036] 2) electroplating an aluminum film layer on the surface of the pretreated brake disc substrate, wherein the thickness of the aluminum film layer is 15 μm, to obtain a brake disc substrate coated with an aluminum film;

[0037] 3) 10 g of zirconium propionate, 10 g of titanium sulfate, 5 g of ferrocene dicarboxylic acid, 20 g of glacial acetic acid and 100 g of dichloromethane were mixed and then added into a reactor for hydrothermal reaction at a temperature of 120° C. for 10 h. After the reaction was completed, the mixture was centrifuged, and the solid product was washed with dichloromethane and dried to obtain a spray coating;

[0038] 4) The spray coating obtained in step 3) is used to form a wear-resistant coating with a thickness of 600 μm on the aluminum film surface of the brake disc substrate by a plasma spraying process, wherein the spraying current is 300A, the spraying voltage is 40V, the powder feeding rate is 3.5g / min, the argon flow rate is 120SCFH, the hydrogen flow rate is 20SCFH, the powder feeding direction is 90°, the spraying distance is 500mm, and the spraying speed is 25mm / s;

[0039] 5) heat treating the wear-resistant coating of the brake disc substrate at a heat treatment temperature of 620° C. for a heat treatment time of 1.5 h to obtain a heat-treated brake disc substrate;

[0040] 6) The aluminum film layer and the wear-resistant coating of the brake disc substrate were immersed in 10g / L H2SO4 and 30g / L NaCl electrolyte for electrolysis at a current density of 0.04A·cm -2 The electrolysis time is 30 minutes. After the electrolysis is completed, the brake disc substrate is taken out, washed with water, and dried to obtain the electrolyzed brake disc substrate;

[0041] 7) The wear-resistant coating of the brake disc substrate after electrolysis is subjected to secondary heat treatment at a temperature of 480° C. for a time of 2 h to obtain the high-strength automobile brake disc.

[0042] Example 2

[0043] This embodiment provides a method for preparing a high-strength automobile brake disc, comprising the following steps:

[0044] 1) grinding and sandblasting the surface of a cast aluminum alloy brake disc substrate to obtain a pretreated brake disc substrate, wherein the aluminum alloy brake disc substrate comprises the following components by mass fraction: Si 6.8%, Mg 0.4%, Fe 0.3%, Cu 0.2%, and the balance Al;

[0045] 2) electroplating an aluminum film layer on the surface of the pretreated brake disc substrate, wherein the thickness of the aluminum film layer is 15 μm, to obtain a brake disc substrate coated with an aluminum film;

[0046] 3) 15 g of zirconium propionate, 10 g of titanium sulfate, 8 g of ferrocene dicarboxylic acid, 20 g of glacial acetic acid and 100 g of dichloromethane were mixed and then added into a reactor for hydrothermal reaction at a temperature of 120° C. for 10 h. After the reaction was completed, the mixture was centrifuged, and the solid product was washed with dichloromethane and dried to obtain a spray coating;

[0047] 4) The spray coating obtained in step 3) is used to form a wear-resistant coating with a thickness of 610 μm on the aluminum film surface of the brake disc substrate by a plasma spraying process, wherein the spraying current is 300A, the spraying voltage is 40V, the powder feeding rate is 3.5g / min, the argon flow rate is 120SCFH, the hydrogen flow rate is 20SCFH, the powder feeding direction is 90°, the spraying distance is 500mm, and the spraying speed is 25mm / s;

[0048] 5) heat treating the wear-resistant coating of the brake disc substrate at a heat treatment temperature of 620° C. for a heat treatment time of 2 h to obtain a heat-treated brake disc substrate;

[0049] 6) The aluminum film layer and the wear-resistant coating of the brake disc substrate were immersed in 10g / L H2SO4 and 30g / L NaCl electrolyte for electrolysis at a current density of 0.03A·cm -2 The electrolysis time is 30 minutes. After the electrolysis is completed, the brake disc substrate is taken out, washed with water, and dried to obtain the electrolyzed brake disc substrate;

[0050] 7) The wear-resistant coating of the brake disc substrate after electrolysis is subjected to secondary heat treatment at a temperature of 500° C. for a time of 2 h to obtain the high-strength automobile brake disc.

[0051] Example 3

[0052] This embodiment provides a method for preparing a high-strength automobile brake disc, comprising the following steps:

[0053] 1) grinding and sandblasting the surface of a cast aluminum alloy brake disc substrate to obtain a pretreated brake disc substrate, wherein the aluminum alloy brake disc substrate comprises the following components by mass fraction: Si 6.8%, Mg 0.4%, Fe 0.3%, Cu 0.2%, and the balance Al;

[0054] 2) electroplating an aluminum film layer on the surface of the pretreated brake disc substrate, wherein the thickness of the aluminum film layer is 15 μm, to obtain a brake disc substrate coated with an aluminum film;

[0055] 3) 15 g of zirconium propionate, 12 g of titanium sulfate, 8 g of ferrocene dicarboxylic acid, 20 g of glacial acetic acid and 100 g of dichloromethane were mixed and then added into a reactor for hydrothermal reaction at a temperature of 130° C. for 12 h. After the reaction was completed, the mixture was centrifuged, and the solid product was washed with dichloromethane and dried to obtain a spray coating;

[0056] 4) The spray coating obtained in step 3) is used to form a wear-resistant coating with a thickness of 620 μm on the aluminum film surface of the brake disc substrate by a plasma spraying process, wherein the spraying current is 300A, the spraying voltage is 40V, the powder feeding rate is 3.5g / min, the argon flow rate is 120SCFH, the hydrogen flow rate is 20SCFH, the powder feeding direction is 90°, the spraying distance is 500mm, and the spraying speed is 25mm / s;

[0057] 5) heat treating the wear-resistant coating of the brake disc substrate at a heat treatment temperature of 620° C. for a heat treatment time of 2.5 h to obtain a heat-treated brake disc substrate;

[0058] 6) The aluminum film layer and the wear-resistant coating of the brake disc substrate were immersed in 10g / L H2SO4 and 30g / L NaCl electrolyte for electrolysis at a current density of 0.04A·cm -2 The electrolysis time is 30 minutes. After the electrolysis is completed, the brake disc substrate is taken out, washed with water, and dried to obtain the electrolyzed brake disc substrate;

[0059] 7) The wear-resistant coating of the brake disc substrate after electrolysis is subjected to secondary heat treatment at a temperature of 490° C. for a time of 2.5 h to obtain the high-strength automobile brake disc.

[0060] Comparative Example 1

[0061] This comparative example provides a method for preparing a high-strength automobile brake disc, which differs from Example 1 in that in step 3), 10 g of zirconium propionate, 10 g of titanium sulfate, 20 g of glacial acetic acid and 100 g of dichloromethane are mixed, then added into a reactor and stirred at 120° C. for 10 h, distilled under reduced pressure, the solid is washed with dichloromethane, and dried to obtain a spray coating.

[0062] Comparative Example 2

[0063] This comparative example provides a method for preparing a high-strength automobile brake disc, comprising the following steps:

[0064] 1) grinding and sandblasting the surface of a cast aluminum alloy brake disc substrate to obtain a pretreated brake disc substrate, wherein the aluminum alloy brake disc substrate comprises the following components by mass fraction: Si 6.8%, Mg 0.4%, Fe 0.3%, Cu 0.2%, and the balance Al;

[0065] 2) electroplating an aluminum film layer on the surface of the pretreated brake disc substrate, wherein the thickness of the aluminum film layer is 15 μm, to obtain a brake disc substrate coated with an aluminum film;

[0066] 3) 10 g of zirconium propionate, 10 g of titanium sulfate, 5 g of ferrocene dicarboxylic acid, 20 g of glacial acetic acid and 100 g of dichloromethane were mixed and then added into a reactor for hydrothermal reaction at a temperature of 120° C. for 10 h. After the reaction was completed, the mixture was centrifuged, and the solid product was washed with dichloromethane and dried to obtain a spray coating;

[0067] 4) The spray coating obtained in step 3) is used to form a wear-resistant coating with a thickness of 600 μm on the aluminum film surface of the brake disc substrate by a plasma spraying process, wherein the spraying current is 300A, the spraying voltage is 40V, the powder feeding rate is 3.5g / min, the argon flow rate is 120SCFH, the hydrogen flow rate is 20SCFH, the powder feeding direction is 90°, the spraying distance is 500mm, and the spraying speed is 25mm / s;

[0068] 5) heat treating the wear-resistant coating of the brake disc substrate at a heat treatment temperature of 620° C. for a heat treatment time of 1.5 h to obtain a heat-treated brake disc substrate;

[0069] 6) The wear-resistant coating of the heat-treated brake disc substrate is subjected to secondary heat treatment at a temperature of 480° C. for a heat treatment time of 2 h to obtain an automobile brake disc.

[0070] Comparative Example 3

[0071] This comparative example provides a method for preparing a high-strength automobile brake disc, comprising the following steps:

[0072] 1) grinding and sandblasting the surface of a cast aluminum alloy brake disc substrate to obtain a pretreated brake disc substrate, wherein the aluminum alloy brake disc substrate comprises the following components by mass fraction: Si 6.8%, Mg 0.4%, Fe 0.3%, Cu 0.2%, and the balance Al;

[0073] 2) electroplating an aluminum film layer on the surface of the pretreated brake disc substrate, wherein the thickness of the aluminum film layer is 15 μm, to obtain a brake disc substrate coated with an aluminum film;

[0074] 3) 10 g of zirconium propionate, 10 g of titanium sulfate, 5 g of ferrocene dicarboxylic acid, 20 g of glacial acetic acid and 100 g of dichloromethane were mixed and then added into a reactor for hydrothermal reaction at a temperature of 120° C. for 10 h. After the reaction was completed, the mixture was centrifuged, and the solid product was washed with dichloromethane and dried to obtain a spray coating;

[0075] 4) The spray coating obtained in step 3) is used to form a wear-resistant coating with a thickness of 600 μm on the aluminum film surface of the brake disc substrate by a plasma spraying process, wherein the spraying current is 300A, the spraying voltage is 40V, the powder feeding rate is 3.5g / min, the argon flow rate is 120SCFH, the hydrogen flow rate is 20SCFH, the powder feeding direction is 90°, the spraying distance is 500mm, and the spraying speed is 25mm / s;

[0076] 5) The aluminum film layer and the wear-resistant coating of the brake disc substrate were immersed in 10g / L H2SO4 and 30g / L NaCl electrolyte for electrolysis at a current density of 0.04A·cm -2 The electrolysis time is 30 minutes. After the electrolysis is completed, the brake disc substrate is taken out, washed with water, and dried to obtain the electrolyzed brake disc substrate;

[0077] 6) The wear-resistant coating of the brake disc substrate after electrolysis is heat treated at a temperature of 480° C. for a time of 2 h to obtain the high-strength automobile brake disc.

[0078] Test Case

[0079] The surface hardness, coating tensile strength and friction and wear of the brake discs prepared in the above embodiments and comparative examples were tested at 100° C. The test results are shown in Table 1.

[0080] Table 1

[0081]

[0082] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for preparing a high-strength automobile brake disc, characterized in that: The steps include: 1) Electroplating an aluminum film layer on the surface of a brake disc substrate to obtain a brake disc substrate coated with an aluminum film; 2) Mixing zirconium propionate, titanium sulfate, ferrocene dicarboxylic acid, glacial acetic acid and a solvent, and then subjecting the mixture to a hydrothermal reaction. After the reaction is completed, centrifuging, washing and drying the mixture to obtain a spray coating; 3) Using a plasma spraying process to form a wear-resistant coating on the aluminum film surface of the brake disc substrate; 4) heat treating the wear-resistant coating of the brake disc substrate to obtain a heat-treated brake disc substrate; 5) The aluminum film layer and the wear-resistant coating of the brake disc substrate are immersed in an acid electrolyte for electrolysis. After the electrolysis is completed, the brake disc substrate is taken out, washed with water, and dried to obtain an electrolyzed brake disc substrate; 6) performing secondary heat treatment on the wear-resistant coating of the brake disc substrate after electrolysis to obtain the high-strength automobile brake disc; The hydrothermal reaction temperature is 100-140°C, and the hydrothermal reaction time is 8-15h; Step 4) The heat treatment temperature is 580-640°C and the heat treatment time is 1-3h; Step 5) The solutes in the neutral-acid electrolyte are sulfuric acid and sodium chloride, wherein the concentration of sulfuric acid is 5-15 g / L and the concentration of sodium chloride is 25-35 g / L; The current density in the electrolysis step is 0.02-0.04A•cm -2 , electrolysis time is 20-40min; In step 6), the secondary heat treatment temperature is 460-520°C, and the secondary heat treatment time is 1-3h.

2. The method for preparing a high-strength automobile brake disc according to claim 1, characterized in that: In step 2), the mass ratio of zirconium propionate, titanium sulfate, ferrocenedicarboxylic acid and glacial acetic acid is (8-15): (8-15): (5-10): (20-50).

3. The method for preparing a high-strength automobile brake disc according to claim 1, characterized in that: The thickness of the aluminum film layer is 10-20 μm.

4. The method for preparing a high-strength automobile brake disc according to claim 1, characterized in that: The mass ratio of the glacial acetic acid to the solvent is (0.2-1):

1.

5. The method for preparing a high-strength automobile brake disc according to claim 1, characterized in that: The solvent in step 2) is dichloromethane; The washing step is performed using dichloromethane.

6. The method for preparing a high-strength automobile brake disc according to claim 1, characterized in that: The thickness of the wear-resistant coating in step 3) is 500-700 μm; In the plasma spraying process, the spraying current is 300-350A, the spraying voltage is 40V, the powder feeding rate is 3.5-4.0g / min, the argon flow rate is 120-130SCFH, the hydrogen flow rate is 20-25SCFH, the powder feeding direction is 90°, the spraying distance is 500-600mm, and the spraying speed is 20-30mm / s.

7. The method for preparing a high-strength automobile brake disc according to claim 1, characterized in that: Before electroplating the aluminum film layer on the surface of the brake disc substrate in step 1), the step of grinding and sandblasting the surface of the brake disc substrate is also included; The brake disc substrate is an aluminum alloy brake disc substrate; the aluminum alloy brake disc substrate, calculated by mass fraction, includes the following components: Si 6.2-6.9%, Mg 0.3-0.4%, Fe0.2-0.3%, Cu0.1-0.2%, and the balance is Al.

8. A high-strength automobile brake disc, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 7.

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