阅读说明：本技术 汽车轮毂喷粉前表面处理工艺 (Surface treatment process before automobile hub powder spraying ) 是由 陈彦广 蔡景坤 陈艺文 朱银银 顾建军 于 2019-09-25 设计创作，主要内容包括：本发明提供汽车轮毂喷粉前表面处理工艺,依次包括预清洗处理、脱脂处理、水洗处理、酸洗处理、第一次纯水洗处理、钝化处理、第二次纯水洗处理；所述钝化处理工序之后还包括封闭处理工序和第三次纯水洗处理工序。本发明的有益效果是可以完全除去轮毂表面的油污、铝屑等杂质,且可以在轮毂表面形成洁净的、适宜的转化膜,为后序涂装提供较好的基材表面。(The invention provides a surface treatment process before powder spraying of an automobile hub, which sequentially comprises pre-cleaning treatment, degreasing treatment, water washing treatment, acid washing treatment, primary pure water washing treatment, passivation treatment and secondary pure water washing treatment; the passivation treatment process also comprises a sealing treatment process and a third pure water washing treatment process. The invention has the advantages that the invention can completely remove impurities such as oil stain, aluminum scraps and the like on the surface of the hub, and can form a clean and proper conversion coating on the surface of the hub, thereby providing a better substrate surface for subsequent coating.)

1. The surface treatment process before powder spraying of the automobile hub sequentially comprises pre-cleaning treatment, degreasing treatment, washing treatment, acid washing treatment, primary pure water washing treatment, passivation treatment and secondary pure water washing treatment; the method is characterized in that: the passivation treatment process also comprises a sealing treatment process and a third pure water washing treatment process.

2. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the sealing treatment process specifically comprises the steps of spraying cleaning solution 1 in a reaction tank and then soaking the hub; the cleaning solution 1 is a mixed solution obtained by mixing an antirust sealing agent and water, wherein the antirust sealing agent accounts for 0.03-0.3% of the total amount of the mixed solution, the temperature is 40-50 ℃, the spray pressure is 0.06-0.08MPa, the spray time is 60s, and the soaking time is 90 s.

3. The process for treating the surface of the automobile hub before powder spraying according to claim 2, which is characterized in that: the rust removal sealing agent consists of the following components in parts by mass: 20-30 parts of coupling aniline, 20-40 parts of benzoic acid, 10-18 parts of sodium nitrite, 10-20 parts of dilute acetic acid, 5-12 parts of ethanol, 1-5 parts of a stabilizer, 100 parts of distilled water, 4-12 parts of acrylic acid and 2-5 parts of a cross-linking agent.

4. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the pre-cleaning treatment process specifically comprises the step of spraying and cleaning the hub for multiple times by using hot water in a reaction tank, wherein the water temperature is 40-60 ℃, the spraying pressure is 0.08-0.1MPa, and the spraying time is 60 s.

5. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the degreasing treatment process comprises two degreasing treatment processes, specifically, a cleaning solution 2 is used for spraying and cleaning the hub in the reaction tank; the temperature of the cleaning liquid 2 in the first degreasing treatment process is 40-50 ℃, the spray pressure is 0.1-0.12MPa, and the spray time is 60 s; the temperature of the cleaning liquid 2 in the second degreasing treatment process is 50-60 ℃, the spray pressure is 0.1-0.12MPa, and the spray time is 60 s.

6. The process for treating the surface of the automobile hub before powder spraying according to claim 6, which is characterized in that: the cleaning liquid 2 is a mixed liquid obtained by mixing an alkaline degreasing agent and water, wherein the alkaline degreasing agent accounts for 3% -6% of the total amount of the mixed liquid.

7. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the washing treatment procedure is that tap water is used for repeatedly spraying and cleaning the hub for many times in the reaction tank, the temperature is kept at normal temperature, the spraying pressure is 0.06-0.1MPa, and the spraying time is 40 s; the acid cleaning process is to spray and clean the hub by using 0.5 percent sulfuric acid solution in the reaction tank, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s.

8. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the first pure water washing treatment process specifically comprises the steps of spraying and cleaning the hub for multiple times by using pure water in a reaction tank until the last spraying and cleaning is finished, wherein the PH value of liquid in the reaction tank is between 6.5 and 7.5, and the conductivity of the pure water is less than 500 mu s/cm; the second pure water washing treatment process is to spray and clean the hub for several times in the reaction tank with pure water, wherein the spraying time is 60s, and the conductivity of the pure water is less than 50 mus/cm.

9. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the passivation treatment process specifically comprises the steps of spraying a mixed solution of 4595 aluminum chromium-free passivator and water in a reaction tank and then soaking the hub; wherein the 4595 aluminum chromium-free passivator accounts for 3% of the total amount of the mixed solution; the spraying pressure is 0.06-0.08MPa, the spraying time is 60s, and the soaking time is 30 s.

10. The process for treating the surface of the automobile hub before powder spraying according to claim 1, which is characterized in that: the third pure water washing treatment procedure comprises two pure water washing processes, specifically, a hub is cleaned by spraying pure water in a reaction tank; in the primary pure water washing process, the conductivity of pure water is less than 20 mus/cm, the temperature is normal temperature, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s; in the pure water washing process again, the conductivity of the pure water is less than 10 mus/cm, the temperature is normal temperature, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s.

Technical Field

The invention belongs to the field of hub manufacturing, and particularly relates to a surface treatment process before powder spraying of an automobile hub.

Background

In the production and manufacturing process of the automobile aluminum alloy wheel hub, after the wheel hub turning process is completed, emulsion, oil stain, aluminum scraps, other impurities and the like which are adhered to the surface of a wheel hub workpiece need to be cleaned, and the surface of the wheel hub needs to be dry and comfortable, and the next process can be switched to.

The Chinese invention patent with patent publication number CN 104014504A and publication number 2014.09.03 discloses a hub surface pretreatment process, which comprises the following steps: a. the method comprises the following steps of (1) first hot water washing treatment, b, pre-degreasing treatment, c, degreasing treatment, d, second hot water washing treatment, e, acid washing treatment, f, first pure water washing treatment, g, chromium-free passivation treatment and h, second pure water washing treatment; however, in the treatment process of the invention, direct water washing after passivation may cause incomplete and closed passivation film, and further affect the whole passivation effect, so that the passivation film of the hub is incomplete, and the subsequent processing and manufacturing are affected.

Disclosure of Invention

The invention aims to solve the problem of providing a surface treatment process before powder spraying of an automobile hub, and the hub adopting the treatment process can completely remove impurities such as oil stains and aluminum scraps on the surface, can form a clean and proper conversion film on the surface of the hub, and provides a better substrate surface for subsequent coating.

In order to solve the technical problems, the invention adopts the technical scheme that: the surface treatment process before automobile hub powder spraying comprises the following steps: sequentially comprises pre-cleaning treatment, degreasing treatment, water washing treatment, acid washing treatment, primary pure water washing treatment, passivation treatment and secondary pure water washing treatment; the passivation treatment process also comprises a sealing treatment process and a third pure water washing treatment process.

Further, the sealing treatment process is to soak the hub after spraying the cleaning solution 1 in the reaction tank; the cleaning solution 1 is a mixed solution obtained by mixing an antirust sealing agent and water, wherein the antirust sealing agent accounts for 0.03-0.3% of the total amount of the mixed solution, the temperature of the mixed solution 3 is 40-50 ℃, the spray pressure is 0.06-0.08MPa, the spray time is 60s, and the soaking time is 90 s.

Further, the rust removal sealing agent consists of the following components in parts by mass: 20-30 parts of coupling aniline, 20-40 parts of benzoic acid, 10-18 parts of sodium nitrite, 10-20 parts of dilute acetic acid, 5-12 parts of ethanol, 1-5 parts of a stabilizer, 100 parts of distilled water, 4-12 parts of acrylic acid and 2-5 parts of a cross-linking agent.

Further, the pre-cleaning treatment process is to spray and clean the hub for multiple times by using hot water in the reaction tank, wherein the water temperature is 40-60 ℃, the spray pressure is 0.08-0.1MPa, and the spray time is 60 s.

Further, the degreasing treatment process comprises two degreasing treatment processes, specifically, a hub is sprayed and cleaned in the reaction tank by using a cleaning solution 2; the temperature of the cleaning liquid 2 in the first degreasing treatment process is 40-50 ℃, the spray pressure is 0.1-0.12MPa, and the spray time is 60 s; the temperature of the cleaning liquid 2 in the second degreasing treatment process is 50-60 ℃, the spray pressure is 0.1-0.12MPa, and the spray time is 60 s.

Further, the cleaning liquid 2 is a mixed liquid obtained by mixing an alkaline degreasing agent and water, wherein the alkaline degreasing agent accounts for 3% -6% of the total amount of the mixed liquid.

Further, the washing treatment procedure is that tap water is used for repeatedly spraying and cleaning the hub for multiple times in the reaction tank, the temperature is kept at normal temperature, the spraying pressure is 0.06-0.1MPa, and the spraying time is 40 s; the acid cleaning process is to spray and clean the hub by using 0.5 percent sulfuric acid solution in the reaction tank, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s.

Further, the first pure water washing treatment process specifically comprises the steps of spraying and cleaning the hub for multiple times by using pure water in a reaction tank until the pH value of liquid in the reaction tank is between 6.5 and 7.5 after the last spraying and cleaning, wherein the conductivity of the pure water is less than 500 mu s/cm; the second pure water washing treatment process is to spray and clean the hub for several times in the reaction tank with pure water, wherein the spraying time is 60s, and the conductivity of the pure water is less than 50 mus/cm.

Further, the passivation treatment process specifically comprises the steps of spraying a mixed solution of 4595 aluminum chromium-free passivator and water in a reaction tank and then soaking the hub; wherein the 4595 aluminum chromium-free passivator accounts for 3% of the total amount of the mixed solution; the spraying pressure is 0.06-0.08MPa, the spraying time is 60s, and the soaking time is 30 s.

Further, the third pure water washing treatment process comprises two pure water washing processes, specifically, a hub is cleaned by spraying pure water in a reaction tank; in the primary pure water washing process, the conductivity of pure water is less than 20 mus/cm, the temperature is normal temperature, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s; in the pure water washing process again, the conductivity of the pure water is less than 10 mus/cm, the temperature is normal temperature, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s.

The invention has the advantages and positive effects that:

1. the process adds a sealing procedure, so that a passivation film formed in the passivation procedure can be sealed and protected, the quality of the hub is improved, and the acid and alkali resistance of the hub can be improved;

2. in the process, the water washing procedures are arranged after the degreasing treatment, the acid washing treatment and the sealing treatment, so that the hub can be washed more thoroughly, and the hub is kept clean before entering the next procedure without reaction liquid of the previous procedure;

3. the hub treated by the process has good cleaning effect, impurities on the surface of the hub are thoroughly removed, a clean and proper conversion film is formed on the surface of the hub, the film layer is flat and full, transparent and bright, wear-resistant and corrosion-resistant, the corrosion of corrosive media in the environment to metal parts can be effectively isolated, and the conversion film can improve the binding force between the substrate and a rear coating.

Drawings

FIG. 1 is a process flow diagram of a surface treatment process before powder spraying of an automobile hub according to the present invention;

FIG. 2 is a diagram showing the effect of the hub after the first surface treatment process before powder spraying of the automobile hub according to the embodiment of the invention;

FIG. 3 is a diagram showing the effect of the hub after the second embodiment of the surface treatment process for automobile hub powder spraying according to the present invention;

FIG. 4 is a diagram showing the effect of the hub after the third treatment of the embodiment of the surface treatment process for automobile hub powder spraying according to the invention;

FIG. 5 is a diagram of the hub effect after the fourth treatment in the embodiment of the surface treatment process for automobile hub powder spraying according to the invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings.

As shown in fig. 1, the surface treatment process before powder spraying of the automobile hub sequentially comprises pre-cleaning treatment, degreasing treatment, water washing treatment, acid washing treatment, primary pure water washing treatment, passivation treatment and secondary pure water washing treatment; the passivation treatment process also comprises a sealing treatment process and a third pure water washing treatment process.

Further, the sealing treatment process is to soak the hub after spraying the cleaning solution 1 in the reaction tank; the cleaning solution 1 is a mixed solution obtained by mixing an antirust sealing agent and water, wherein the antirust sealing agent accounts for 0.03-0.3% of the total amount of the mixed solution, the temperature of the mixed solution 3 is 40-50 ℃, the spray pressure is 0.06-0.08MPa, the spray time is 60s, and the soaking time is 90 s. The sealing treatment process is arranged, so that the film layer after the passivation reaction can be sealed into an integral smooth film layer, the passivation film is protected, and meanwhile, the quality of the hub and the acid and alkali resistance of the hub can be improved.

Further, the rust removal sealing agent consists of the following components in parts by mass: 20-30 parts of coupling aniline, 20-40 parts of benzoic acid, 10-18 parts of sodium nitrite, 10-20 parts of dilute acetic acid, 5-12 parts of ethanol, 1-5 parts of a stabilizer, 100 parts of distilled water, 4-12 parts of acrylic acid and 2-5 parts of a cross-linking agent.

Further, the pre-cleaning treatment process is to spray and clean the hub for multiple times by using hot water in the reaction tank, wherein the water temperature is 40-60 ℃, the spray pressure is 0.08-0.1MPa, and the spray time is 60 s. The process is to wash away the impurities such as dust, iron filings and the like on the surface of the hub by hot water, and when the obvious impurities cannot be seen by naked eyes, the cleaning is thorough.

Further, the degreasing treatment process comprises two degreasing treatment processes, specifically, a hub is sprayed and cleaned in the reaction tank by using a cleaning solution 2; the temperature of the cleaning liquid 2 in the first degreasing treatment process is 40-50 ℃, the spray pressure is 0.1-0.12MPa, and the spray time is 60 s; the temperature of the cleaning liquid 2 in the second degreasing treatment process is 50-60 ℃, the spray pressure is 0.1-0.12MPa, and the spray time is 60 s. The degreasing step is to remove grease on the surface of the hub.

Further, the cleaning liquid 2 is a mixed liquid obtained by mixing an alkaline degreasing agent and water, wherein the content of the alkaline degreasing agent is 3% -6%.

Further, the washing treatment procedure is that tap water is used for repeatedly spraying and cleaning the hub for multiple times in the reaction tank, the temperature is kept at normal temperature, the spraying pressure is 0.06-0.1MPa, and the spraying time is 40 s; the acid cleaning process is to spray and clean the hub by using 0.5 percent sulfuric acid solution in the reaction tank, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s. The water washing treatment process is to thoroughly wash the residual degreasing agent on the hub, and the hub can be repeatedly washed by tap water for several times, so that the alkaline substances in the hub are prevented from reacting with the acid in the next process to influence the action of the next process. The acid washing step is intended to remove the oxide film on the hub surface.

Further, the first pure water washing treatment process specifically comprises the steps of spraying and cleaning the hub for multiple times by using pure water in a reaction tank until the pH value of liquid in the reaction tank is between 6.5 and 7.5 after the last spraying and cleaning, wherein the conductivity of the pure water is less than 500 mu s/cm; the second pure water washing treatment process is to spray and clean the hub for several times in the reaction tank with pure water, wherein the spraying time is 60s, and the conductivity of the pure water is less than 50 mus/cm. The first pure water washing treatment process is to remove the residual acid solution on the surface of the hub; the second pure water washing step is to remove the passivation solution remaining on the surface of the hub.

Further, the passivation treatment process specifically comprises the steps of spraying a mixed solution of 4595 aluminum chromium-free passivator and water in a reaction tank and then soaking the hub; wherein the 4595 aluminum chromium-free passivator accounts for 3% of the total amount of the mixed solution; the spraying pressure is 0.06-0.08MPa, the spraying time is 60s, and the soaking time is 30 s. The passivation treatment process is to form a layer of passivation film on the surface of the hub, so that the quality and the corrosion resistance of the front hub are improved, and the later-stage powder spraying treatment of the hub is facilitated.

Further, the third pure water washing treatment process comprises two pure water washing processes, specifically, a hub is cleaned by spraying pure water in a reaction tank; in the primary pure water washing process, the conductivity of pure water is less than 20 mus/cm, the temperature is normal temperature, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s; in the pure water washing process again, the conductivity of the pure water is less than 10 mus/cm, the temperature is normal temperature, the spray pressure is 0.06-0.08MPa, and the spray time is 60 s. The third pure water washing treatment process is to remove residual liquid on the surface of the hub in the sealing treatment process, and simultaneously thoroughly clean the coated hub to prepare for later powder spraying.