CN111013991A - Paint spraying process for automobile brake drum - Google Patents
Paint spraying process for automobile brake drum Download PDFInfo
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- CN111013991A CN111013991A CN201911402547.3A CN201911402547A CN111013991A CN 111013991 A CN111013991 A CN 111013991A CN 201911402547 A CN201911402547 A CN 201911402547A CN 111013991 A CN111013991 A CN 111013991A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/14—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to metal, e.g. car bodies
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
- B05D3/0218—Pretreatment, e.g. heating the substrate
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
- B05D3/0254—After-treatment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/04—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by exposure to gases
- B05D3/0406—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by exposure to gases the gas being air
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/10—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by other chemical means
- B05D3/102—Pretreatment of metallic substrates
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/50—Multilayers
- B05D7/52—Two layers
- B05D7/54—No clear coat specified
- B05D7/544—No clear coat specified the first layer is let to dry at least partially before applying the second layer
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/73—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals characterised by the process
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D2451/00—Type of carrier, type of coating (Multilayers)
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Wood Science & Technology (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
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Abstract
The invention discloses a paint spraying process for an automobile brake drum, which comprises the following steps: the method comprises the following steps: preprocessing an automobile brake drum workpiece; step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one; step three: and (3) performing paint spraying treatment on the automobile brake drum workpiece treated in the step (II), wherein the surface oxidation treatment specifically comprises the following steps: firstly, preparing an oxidant solution, then placing the automobile brake drum workpiece treated in the first step into the oxidant solution for dipping, and taking out and drying the automobile brake drum workpiece by cold air after the dipping is finished; the paint spraying process improves the adhesive force of paint on the upper surface of the automobile brake drum workpiece, and has excellent salt spray test effect and prolonged service life.
Description
Technical Field
The invention relates to the field of automobile accessory paint spraying processes, in particular to a paint spraying process for an automobile brake drum.
Background
The brake drum is integrally cast from high-strength gray cast iron or alloy cast iron containing Cr. The brake drum has simple structure, convenient processing, large heat capacity and large mass, and is mainly used for medium and heavy automobiles. In the production process of the brake drum, the brake drum needs to be subjected to paint spraying operation after being formed, the brake drum obtained by the existing paint spraying process is low in paint adhesion, and the phenomenon of paint falling is easy to occur after the brake drum is used for a period of time.
Disclosure of Invention
The invention aims to solve at least one technical problem in the prior art and provides a paint spraying process for an automobile brake drum.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a paint spraying process for an automobile brake drum comprises the following steps:
the method comprises the following steps: preprocessing an automobile brake drum workpiece;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
step three: and D, performing paint spraying treatment on the automobile brake drum workpiece treated in the step two.
Preferably, in the first step, the pretreatment comprises alkali washing, water washing and drying in sequence, wherein the pH of alkali liquor in the alkali washing is 9-11, the alkali washing temperature is 50-70 ℃, and the alkali washing time is 5-10 min.
Preferably, in the second step, the surface oxidation treatment specifically comprises: firstly preparing an oxidant solution, then placing the automobile brake drum workpiece treated in the first step into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
Preferably, the impregnation is ultrasonic impregnation.
Preferably, the impregnation comprises the following three stages, in order:
the first stage is as follows: the dipping temperature is 50-60 ℃, and the dipping time is 20-30 min;
and a second stage: the dipping temperature is 100-150 ℃, and the dipping time is 5-10 min;
and a third stage: the dipping temperature is 170-190 ℃, and the dipping time is 5-10 min.
Preferably, in the second step, before the surface oxidation treatment, a surface roughness treatment is further included, and the surface roughness treatment specifically includes: the surface roughness of the brake drum workpiece is treated to 10-30 μm.
Preferably, in the third step, before the painting treatment, an additional step one is further included, where the additional step one specifically is: preheating the automobile brake drum workpiece at 50-60 deg.c for 5-10 min.
Preferably, in the third step, the paint spraying treatment comprises spraying a primer and spraying a finish paint in sequence, wherein the spraying of the primer is performed at least twice, and the total thickness of the primer is 8-30 μm; the thickness of the finish paint is 5-20 μm.
Preferably, in the third step, an additional step two is further included after the finish paint is sprayed, where the additional step two specifically is: and baking and curing the automobile brake drum workpiece sprayed with the finish paint at the baking temperature of 150-220 ℃ for 30-50 min.
Preferably, in the third step, the spraying manner of the painting process is: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the workpiece of the automobile brake drum is 15-25cm, the spraying direction of the spray gun is vertical to the surface of the workpiece of the automobile brake drum, and the moving speed of the spray gun is kept at 40-50 cm/s.
The invention has the beneficial effects that:
(1) according to the paint spraying process, the surface oxidation treatment is carried out on the automobile brake drum workpiece, so that the polar component with carbon molecules on the surface of the workpiece is increased, the surface tension of the automobile brake drum workpiece is reduced, the adhesive force of paint on the upper surface of the automobile brake drum workpiece is improved, the salt spray test effect of the automobile brake drum is excellent, and the service life of the automobile brake drum is prolonged.
(2) The invention adopts at least two times of spraying the priming paint, can effectively ensure the thickness of the priming paint and ensure the paint spraying quality.
(3) According to the invention, the automobile brake drum workpiece is preheated before the primer is sprayed, the adsorption effect of the sprayed primer can be effectively improved, and because the curing component in the primer can be rapidly solidified to form a film when the primer is sprayed on the surface of the workpiece and is contacted with the surface with a certain temperature, the spraying effect is improved.
(4) According to the invention, the automobile brake drum workpiece is subjected to oxidation treatment by controlling the dipping temperature pairs in three stages and by adopting ultrasonic dipping, on one hand, the dipping is carried out at a lower temperature, so that oxidant molecules in an oxidant solution can be slowly diffused and can reach the surface of the workpiece within enough time, and the oxidant molecules are uniformly distributed on the surface of the workpiece, and meanwhile, the solvent molecules in the oxidant solution are not influenced, so that the oxidation concentration is ensured, then, the high-temperature treatment is adopted in the second stage and the third stage, so that the oxidation reaction of the oxidant molecules on the surface of the workpiece is accelerated, and the volatilization of the partial solvent molecules in the temperature stage along with the consumption of the oxidant molecules can ensure the stability of the oxidation concentration to a certain extent, so that the stable performance of the whole oxidation treatment is; on the other hand, ultrasonic impregnation is adopted, the ultrasonic impregnation and the ultrasonic impregnation are combined, the oxidation effect is more uniform, the adhesive force of the paint is also uniform, and therefore the paint spraying effect is improved.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
Example 1
A paint spraying process for an automobile brake drum comprises the following steps:
the method comprises the following steps: pretreating an automobile brake drum workpiece, wherein the pretreatment sequentially comprises alkali washing, water washing and drying;
the pH of the alkali liquor in the alkali washing is 9, the alkali washing temperature is 50 ℃, and the alkali washing time is 5 min.
The alkali liquor can be prepared from alkaline substances such as sodium bicarbonate, sodium carbonate and the like, or can be prepared from commercially available metal cleaning agents to adjust the qualified pH, for example, the metal cleaning agent is a JC-015 metal cleaning agent produced by clean and thorough cleaning agent technology limited of Dongguan;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
the surface oxidation treatment specifically comprises the following steps: firstly preparing an oxidant solution, then putting the automobile brake drum workpiece treated in the step one into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
The impregnation comprises the following three stages in sequence:
the first stage is as follows: the dipping temperature is 50 ℃, and the dipping time is 20 min;
and a second stage: the dipping temperature is 100 ℃, and the dipping time is 5 min;
and a third stage: the impregnation temperature was 170 ℃ and the impregnation time was 5 min.
The oxidizing agent used in this example includes 1 part by weight of potassium dichromate, 0.1 part by weight of triethanolamine, 1 part by weight of ammonium molybdate, 1 part by weight of sodium silicate, and 1 part by weight of surfactant; the surfactant is sodium lauryl sulfate.
Step three: performing paint spraying treatment on the automobile brake drum workpiece treated in the step two, wherein the paint spraying treatment sequentially comprises spraying primer, spraying finish paint and baking and curing; spraying the primer twice, wherein the total thickness of the primer is 8 mu m; the thickness of the finish paint is 5 mu m; the baking temperature is 150 ℃, and the baking time is 30 min.
And (3) preheating the automobile brake drum workpiece before spraying the primer, wherein the preheating temperature is 50 ℃, and the preheating time is 5 min.
The spraying mode of the paint spraying treatment is as follows: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the automobile brake drum workpiece is 15cm, and the spraying direction of the spray gun is vertical to the surface of the automobile brake drum workpiece; the moving speed of the lance was kept at 40 cm/s.
Example 2
A paint spraying process for an automobile brake drum comprises the following steps:
the method comprises the following steps: pretreating an automobile brake drum workpiece, wherein the pretreatment sequentially comprises alkali washing, water washing and drying;
the pH of the alkali liquor in the alkali washing is 10, the alkali washing temperature is 60 ℃, and the alkali washing time is 7 min.
The alkali liquor can be prepared from alkaline substances such as sodium bicarbonate, sodium carbonate and the like, and can also be a commercially available metal cleaning agent, for example, the metal cleaning agent produced by clean cleaning agent technology limited company of Dongguan is JC-015;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
the surface oxidation treatment specifically comprises the following steps: firstly preparing an oxidant solution, then putting the automobile brake drum workpiece treated in the step one into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
The impregnation comprises the following three stages in sequence:
the first stage is as follows: the dipping temperature is 55 ℃, and the dipping time is 25 min;
and a second stage: the dipping temperature is 120 ℃, and the dipping time is 7 min;
and a third stage: the impregnation temperature was 180 ℃ and the impregnation time was 7 min.
The oxidizing agent used in this example includes 3 parts by weight of potassium dichromate, 0.3 part by weight of triethanolamine, 2 parts by weight of ammonium molybdate, 1.5 parts by weight of sodium silicate, and 3 parts by weight of a surfactant; the surfactant is sodium lauryl sulfate.
Step three: performing paint spraying treatment on the automobile brake drum workpiece treated in the step two, wherein the paint spraying treatment sequentially comprises spraying primer, spraying finish paint and baking and curing; spraying the primer twice, wherein the total thickness of the primer is 15 mu m; the thickness of the finish paint is 10 mu m; the baking temperature is 170 ℃ and the baking time is 40 min.
And (3) preheating the automobile brake drum workpiece before spray painting treatment, wherein the preheating temperature is 55 ℃, and the preheating time is 7 min.
The spraying mode of the paint spraying treatment is as follows: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the automobile brake drum workpiece is 20cm, and the spraying direction of the spray gun is vertical to the surface of the automobile brake drum workpiece; the moving speed of the lance was kept at 45 cm/s.
Example 3
A paint spraying process for an automobile brake drum comprises the following steps:
the method comprises the following steps: pretreating an automobile brake drum workpiece, wherein the pretreatment sequentially comprises alkali washing, water washing and drying;
the PH of the alkali liquor in the alkali washing is 11, the alkali washing temperature is 70 ℃, and the alkali washing time is 10 min.
The alkali liquor can be prepared from alkaline substances such as sodium bicarbonate, sodium carbonate and the like, and can also be a commercially available metal cleaning agent, for example, the metal cleaning agent produced by clean cleaning agent technology limited company of Dongguan is JC-015;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
the surface oxidation treatment specifically comprises the following steps: firstly preparing an oxidant solution, then putting the automobile brake drum workpiece treated in the step one into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
The impregnation comprises the following three stages in sequence:
the first stage is as follows: the dipping temperature is 60 ℃, and the dipping time is 30 min;
and a second stage: the dipping temperature is 150 ℃, and the dipping time is 10 min;
and a third stage: the impregnation temperature was 190 ℃ and the impregnation time was 10 min.
The oxidant used in this example includes 10 parts by weight of potassium dichromate, 1 part by weight of triethanolamine, 3 parts by weight of ammonium molybdate, 2 parts by weight of sodium silicate, and 5 parts by weight of surfactant; the surfactant is sodium lauryl sulfate.
Step three: performing paint spraying treatment on the automobile brake drum workpiece treated in the step two, wherein the paint spraying treatment sequentially comprises spraying primer, spraying finish paint and baking and curing; spraying the primer twice, wherein the total thickness of the primer is 10 mu m; the thickness of the finish paint is 20 mu m; the baking temperature is 220 deg.C, and the baking time is 50 min.
The automobile brake drum workpiece is preheated before the paint spraying treatment, the preheating temperature is 60 ℃, and the preheating time is 10 min.
The spraying mode of the paint spraying treatment is as follows: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the automobile brake drum workpiece is 25cm, and the spraying direction of the spray gun is vertical to the surface of the automobile brake drum workpiece; the moving speed of the lance was kept at 50 cm/s.
Example 4
The present embodiment is optimized based on embodiment 2, and specifically, in the second step, before the surface oxidation treatment, a surface roughness treatment is further included, where the surface roughness treatment specifically is: the surface roughness of the automobile brake drum workpiece is treated to 10 microns by quartz sand spraying.
Example 5
The present embodiment is optimized based on embodiment 2, and specifically, in the second step, before the surface oxidation treatment, a surface roughness treatment is further included, where the surface roughness treatment specifically is: the surface roughness of the automobile brake drum workpiece is treated to 20 microns by quartz sand spraying.
Example 6
The present embodiment is optimized based on embodiment 2, and specifically, in the second step, before the surface oxidation treatment, a surface roughness treatment is further included, where the surface roughness treatment specifically is: the surface roughness of the automobile brake drum workpiece is treated to 30 mu m by quartz sand spraying.
Example 7
This example is a further optimization based on example 2, and specifically, the impregnation is ultrasonic impregnation.
Comparative example 1
A paint spraying process for an automobile brake drum comprises the following steps:
the method comprises the following steps: sequentially carrying out alkali washing, water washing and drying on the automobile brake drum workpiece;
the PH of the alkali liquor in the alkali washing is 11, the alkali washing temperature is 70 ℃, and the alkali washing time is 10 min.
The alkali liquor can be prepared from alkaline substances such as sodium bicarbonate, sodium carbonate and the like, and can also be a commercially available metal cleaning agent, for example, the metal cleaning agent produced by clean cleaning agent technology limited company of Dongguan is JC-015;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
the surface oxidation treatment specifically comprises the following steps: firstly preparing an oxidant solution, then putting the automobile brake drum workpiece treated in the step one into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
The impregnation temperature was 60 ℃ and the impregnation time was 60 min.
The oxidant used in this example includes 10 parts by weight of potassium dichromate, 1 part by weight of triethanolamine, 3 parts by weight of ammonium molybdate, 2 parts by weight of sodium silicate, and 5 parts by weight of surfactant; the surfactant is sodium lauryl sulfate.
Step three: performing paint spraying treatment on the automobile brake drum workpiece treated in the step two, wherein the paint spraying treatment sequentially comprises spraying primer, spraying finish paint and baking and curing; spraying the primer twice, wherein the total thickness of the primer is 10 mu m; the thickness of the finish paint is 20 mu m; the baking temperature is 220 deg.C, and the baking time is 50 min.
And (3) preheating the automobile brake drum workpiece before spraying the primer, wherein the preheating temperature is 60 ℃, and the preheating time is 10 min.
The spraying mode of the paint spraying treatment is as follows: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the automobile brake drum workpiece is 25cm, and the spraying direction of the spray gun is vertical to the surface of the automobile brake drum workpiece; the moving speed of the lance was kept at 50 cm/s.
Comparative example 2
A paint spraying process for an automobile brake drum comprises the following steps:
the method comprises the following steps: sequentially carrying out alkali washing, water washing and drying on the automobile brake drum workpiece;
the PH of the alkali liquor in the alkali washing is 11, the alkali washing temperature is 70 ℃, and the alkali washing time is 10 min.
The alkali liquor can be prepared from alkaline substances such as sodium bicarbonate, sodium carbonate and the like, and can also be a commercially available metal cleaning agent, for example, the metal cleaning agent produced by clean cleaning agent technology limited company of Dongguan is JC-015;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
the surface oxidation treatment specifically comprises the following steps: firstly preparing an oxidant solution, then putting the automobile brake drum workpiece treated in the step one into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
The impregnation comprises the following three stages in sequence:
the first stage is as follows: the dipping temperature is 60 ℃, and the dipping time is 30 min;
and a second stage: the dipping temperature is 150 ℃, and the dipping time is 10 min;
and a third stage: the impregnation temperature was 190 ℃ and the impregnation time was 10 min.
The oxidant used in this example includes 10 parts by weight of potassium dichromate, 1 part by weight of triethanolamine, 3 parts by weight of ammonium molybdate, 2 parts by weight of sodium silicate, and 5 parts by weight of surfactant; the surfactant is sodium lauryl sulfate.
Step three: performing paint spraying treatment on the automobile brake drum workpiece treated in the step two, wherein the paint spraying treatment sequentially comprises spraying primer, spraying finish paint and baking and curing; spraying the primer twice, wherein the total thickness of the primer is 10 mu m; the thickness of the finish paint is 20 mu m; the baking temperature is 220 deg.C, and the baking time is 50 min.
The spraying mode of the paint spraying treatment is as follows: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the automobile brake drum workpiece is 25cm, and the spraying direction of the spray gun is vertical to the surface of the automobile brake drum workpiece; the moving speed of the lance was kept at 50 cm/s.
The primer used in the above examples is prepared by mixing the following components in parts by weight: 40 parts of waterborne polyurethane resin, 25 parts of filler (calcium silicate), 1 part of auxiliary agent (ethylene glycol) and 35 parts of water;
the finish paint used in the above examples is prepared by mixing the following components in parts by weight: 65 parts of water-based silicone-acrylate resin, 3 parts of nano colloidal silica, 0.5 part of a crosslinking agent (dicumyl peroxide), 0.5 part of a film-forming aid (propylene glycol), 3 parts of a toughening agent (chloropropene) and 30 parts of water.
The following tests were carried out for examples 1 to 7 and comparative examples 1 and 2, and the test values are shown in Table 1;
salt spray test: and (3) carrying out a 360-hour neutral salt spray test according to GB/T10125 test specifications, carefully observing the corrosion condition of the surface of the workpiece after the salt spray test, recording the corrosion state, wherein the corrosion rate is lower than 0.1%, namely the product is qualified, and the fewer corrosion points are, so that the spraying coverage of the paint is good, and the salt spray is not easy to penetrate through the paint layer to corrode the metal layer of the workpiece.
And (3) testing the adhesive force: reference may be made to ASTM D3359 method a, namely: randomly selecting 1 area on the workpiece, wherein the specification is 150mm multiplied by 150 mm; a sharp blade is used for scratching a fork with an included angle of 60 degrees on a selected area, namely the surface, the depth is required to reach the surface of a workpiece, then a professional pressure sensitive adhesive tape with the width of 25mm is pasted, the surface of the adhesive tape pasted with finish paint is pulled up at a stable speed, the condition that paint layers on two sides of a cutting mark are not more than 1.5mm when the paint layers on the two sides of the cutting mark are uncovered is a qualified product, and the adhesion test value in the following table is the length of the uncovered paint layers on the two sides of the.
TABLE 1 test values of examples 1 to 6 and comparative examples 1 and 2
| Test specimen | Adhesion test value (mm) | Salt spray test (% Corrosion) |
| Example 1 | 0.5 | 0.02 |
| Example 2 | 0.4 | 0.01 |
| Example 3 | 0.6 | 0.03 |
| Example 4 | 0.3 | 0.02 |
| Example 5 | 0.4 | 0.01 |
| Example 6 | 0.5 | 0.03 |
| Example 7 | 0.2 | 0.01 |
| Comparative example 1 | 1.8 | 0.12 |
| Comparative example 2 | 1.7 | 0.13 |
As can be seen from Table 1, the test performances of examples 1-7 are superior to those of comparative examples 1 and 2, wherein the performance of example 7 is better, the test value of the adhesive force is 0.2mm, the corrosion rate of 360h in the salt spray test is only 0.01%, which shows that the corrosion points are fewer, the spraying coverage of the paint is good, and the salt spray is not easy to penetrate through the paint layer and corrode the metal layer of the workpiece; the test values of comparative examples 1 and 2 do not reach the qualified value, and compared with example 2, the impregnation mode of the oxidant affects the performance of the sample, mainly because: on one hand, the low-temperature impregnation is firstly carried out, so that oxidant molecules in an oxidant solution can be slowly diffused and can reach the surface of a workpiece in enough time, the oxidant molecules are uniformly distributed on the surface of the workpiece, meanwhile, solvent molecules in the oxidant solution are not influenced, the oxidation concentration is ensured, then, the high-temperature treatment is adopted in the second stage and the third stage, the oxidation reaction of the oxidant molecules on the surface of the workpiece is accelerated, the volatilization of the partial solvent molecules in the temperature stage along with the consumption of the oxidant molecules can ensure the stability of the oxidation concentration to a certain extent, the stable proceeding of the whole oxidation treatment is ensured, and the oxidation treatment effect is good; on the other hand, ultrasonic impregnation is adopted, and the ultrasonic impregnation are combined, so that the oxidation effect is more uniform; it can also be seen from comparative example 2 that preheating the automobile brake drum workpiece before spraying the primer greatly affects the performance of the sample, and the treatment can effectively improve the adsorption effect of the sprayed primer, because when the primer is sprayed on the surface of the workpiece and is contacted with the surface with a certain temperature, the curing component in the primer can be rapidly solidified to form a film, the phenomenon of tearing is not easy to occur, the salt spray test is excellent, and the adhesive force is correspondingly improved; the spraying effect is improved. Meanwhile, the ultrasonic impregnation adopted in the embodiment 7 enables the oxidation treatment effect to be more uniform, and the adsorption force to the subsequent primer and finish paint to be better, so that the adhesive force of the primer and finish paint is improved to a certain extent; in the embodiment, the primer and the finish paint both adopt water-based paint, and the bonding performance is more excellent according to the similarity and intermiscibility principle.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept of the present invention, and these changes and modifications are all within the scope of the present invention.
Claims (10)
1. The paint spraying process of the automobile brake drum is characterized by comprising the following steps of:
the method comprises the following steps: preprocessing an automobile brake drum workpiece;
step two: carrying out surface oxidation treatment on the automobile brake drum workpiece treated in the step one;
step three: and D, performing paint spraying treatment on the automobile brake drum workpiece treated in the step two.
2. The automobile brake drum paint spraying process according to claim 1, wherein in the first step, the pretreatment comprises alkali washing, water washing and drying sequentially, wherein the pH of alkali liquor in the alkali washing is 9-11, the alkali washing temperature is 50-70 ℃, and the alkali washing time is 5-10 min.
3. The paint spraying process of the automobile brake drum as claimed in claim 1, wherein in the second step, the surface oxidation treatment specifically comprises: firstly preparing an oxidant solution, then placing the automobile brake drum workpiece treated in the first step into the oxidant solution for dipping, and taking out and drying by cold air after the dipping is finished.
4. The process for spray painting an automotive brake drum according to claim 3, wherein the impregnation is ultrasonic impregnation.
5. The process for spray painting an automotive brake drum according to claim 3 or 4, characterized in that said impregnation comprises the following three stages, in sequence:
the first stage is as follows: the dipping temperature is 50-60 ℃, and the dipping time is 20-30 min;
and a second stage: the dipping temperature is 100-150 ℃, and the dipping time is 5-10 min;
and a third stage: the dipping temperature is 170-190 ℃, and the dipping time is 5-10 min.
6. The paint spraying process of the automobile brake drum as claimed in claim 1, wherein in the second step, before the surface oxidation treatment, a surface roughness treatment is further included, and the surface roughness treatment specifically comprises: the surface roughness of the brake drum workpiece is treated to 10-30 μm.
7. The process for spraying paint on an automobile brake drum according to claim 1, wherein in the third step, the painting process further comprises an additional step one, and the additional step one is specifically: preheating the automobile brake drum workpiece at 50-60 deg.c for 5-10 min.
8. The process for spraying paint on an automobile brake drum according to claim 1, wherein in the third step, the paint spraying treatment comprises spraying a primer and spraying a topcoat sequentially, wherein the spraying of the primer is performed at least twice, and the total thickness of the primer is 8-30 μm; the thickness of the finish paint is 5-20 μm.
9. The automobile brake drum paint spraying process according to claim 8, wherein in the third step, an additional step two is further included after the finish paint spraying, and the additional step two specifically comprises: and baking and curing the automobile brake drum workpiece sprayed with the finish paint at the baking temperature of 150-220 ℃ for 30-50 min.
10. The process for spraying paint on the brake drum of the automobile as claimed in claim 1, wherein in the third step, the spraying mode of the paint spraying treatment is as follows: spraying by using a spray gun, wherein the distance between the nozzle of the spray gun and the surface of the workpiece of the automobile brake drum is 15-25cm, the spraying direction of the spray gun is vertical to the surface of the workpiece of the automobile brake drum, and the moving speed of the spray gun is kept at 40-50 cm/s.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911402547.3A CN111013991A (en) | 2019-12-30 | 2019-12-30 | Paint spraying process for automobile brake drum |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911402547.3A CN111013991A (en) | 2019-12-30 | 2019-12-30 | Paint spraying process for automobile brake drum |
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| CN201911402547.3A Pending CN111013991A (en) | 2019-12-30 | 2019-12-30 | Paint spraying process for automobile brake drum |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112620056A (en) * | 2020-12-11 | 2021-04-09 | 江苏特丽亮镀膜科技有限公司 | Paint spraying process for alloy and plastic die castings |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104785427A (en) * | 2015-04-30 | 2015-07-22 | 吴军香 | Vehicle fender-guard paint spraying process |
-
2019
- 2019-12-30 CN CN201911402547.3A patent/CN111013991A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104785427A (en) * | 2015-04-30 | 2015-07-22 | 吴军香 | Vehicle fender-guard paint spraying process |
Non-Patent Citations (5)
| Title |
|---|
| 中国腐蚀与防护学会等: "《腐蚀与防护全书 热喷涂》", 31 December 1992, 化学工业出版社 * |
| 司春波: "《实用涂装工手册》", 31 May 2007, 广东科技出版社 * |
| 宋志伟等: "《水污染控制工程》", 31 July 2013, 中国矿业大学出版社 * |
| 王耀斌: "《国内外汽车维修实用手册》", 31 May 1995, 天津科学技术出版社 * |
| 陆晓华等: "《环境污染控制原理》", 28 February 2010, 华中科技大学出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112620056A (en) * | 2020-12-11 | 2021-04-09 | 江苏特丽亮镀膜科技有限公司 | Paint spraying process for alloy and plastic die castings |
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