CN112725786A - Cobalt-containing phosphating agent, metal piece and surface phosphating method thereof - Google Patents
Cobalt-containing phosphating agent, metal piece and surface phosphating method thereof Download PDFInfo
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- CN112725786A CN112725786A CN202011458271.3A CN202011458271A CN112725786A CN 112725786 A CN112725786 A CN 112725786A CN 202011458271 A CN202011458271 A CN 202011458271A CN 112725786 A CN112725786 A CN 112725786A
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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
- C23C22/05—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 using aqueous solutions
- C23C22/06—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 using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/48—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 using aqueous solutions using aqueous acidic solutions with pH less than 6 not containing phosphates, hexavalent chromium compounds, fluorides or complex fluorides, molybdates, tungstates, vanadates or oxalates
- C23C22/56—Treatment of aluminium or alloys based thereon
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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
-
- 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
- C23C22/76—Applying the liquid by spraying
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- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
Abstract
The invention relates to a cobalt-containing phosphating agent, a metal piece and a surface phosphating method thereof. The phosphating agent is used for surface pretreatment of metal pieces and comprises the following components in parts by weight in 1000 parts: 5-30 parts of phosphoric acid, 3-10 parts of zinc oxide, 0.5-3 parts of magnesium salt, 0.5-3 parts of aluminum salt, 0.5-5 parts of cobalt nitrate and the balance of water. The film formed by the phosphating agent has a delicate structure and firm adhesive force, can generate a continuous, uniform and colored phosphating layer on the surface of a metal piece, and is applied to phosphating treatment before spraying of the surfaces of steel and iron such as cold-rolled plates, hot-rolled plates, angle steel and the like. The phosphating solution has long service life and no waste water, and can be used for phosphating by adopting a brushing mode, a soaking mode, a spraying mode or a combination mode thereof. The adoption temperature is 10-50 ℃, the coating can be dried or naturally dried, the energy consumption is greatly saved, the phosphating time is short, no additional surface adjustment is needed before use, no accelerator is needed, and the operation is simple and time-saving.
Description
Technical Field
The invention relates to the technical field of metal surface treatment, in particular to a cobalt-containing phosphating agent, a metal piece and a surface phosphating method thereof.
Background
To improve the surface properties or appearance of the product, the workpiece is usually surface treated. For example, surface treatment processes for aluminum, iron, and alloys thereof are in great variety of industries. Moreover, most of the work requires a pretreatment before the surface treatment, such as cleaning, degreasing, and phosphating, passivation, etc. of the metal parts for some applications.
Phosphating generally adopts a phosphating agent to pretreat a metal piece so as to form a film layer on the surface of the metal piece, so that subsequent surface treatment is carried out, and the bonding force and the corrosion resistance of a subsequent film are increased. For example, before a metal part is subjected to a spray coating process, it is necessary to form a phosphate on the surface of the metal part to prevent corrosion of the surface of the metal part during the treatment of the metal part and to increase the adhesion between the metal part and the coating. However, the existing phosphating agents have high energy consumption, more precipitates, short service life, poor corrosion resistance and complex operation (surface adjustment is needed before phosphating, the phosphating agent needs to be added into phosphating solution regularly and quantitatively, and the acidity needs to be strictly controlled).
Disclosure of Invention
In view of the above, a cobalt-containing phosphating agent with a delicate structure, firm adhesion, good corrosion resistance, high temperature resistance, low energy consumption and simple operation, a phosphating treatment method for the surface of a metal part and the metal part prepared by phosphating treatment are provided.
A cobalt-containing phosphating agent is used for forming phosphating on the surface of a metal piece and comprises the following components in parts by weight in 1000 parts: 5-30 parts of phosphoric acid, 3-10 parts of zinc oxide, 0.5-3 parts of magnesium salt, 0.5-3 parts of aluminum salt, 0.5-5 parts of cobalt nitrate and the balance of water.
A surface phosphating method for a metal piece comprises the following steps: preparing the phosphating agent, forming phosphating agent solution, brushing, soaking and spraying the phosphating agent solution on the metal piece, performing treatment for a preset time, washing the metal piece with water, and drying.
And a metal member having a surface provided with a phosphate coating formed by the metal member surface phosphate treatment method as described above.
The film formed by the cobalt-containing phosphating agent has the advantages of delicate structure, firm adhesive force, good corrosion resistance, high temperature resistance (no damage caused by baking at 280 ℃), low energy consumption and simple operation, and can be used for phosphating before the spraying of the surface of steel. After the metal piece is brushed, soaked and sprayed with the phosphating agent solution, a phosphating layer formed on the surface is compact in structure and strong in adhesive force, and a subsequent spraying process is facilitated, so that the adhesion formation of a coating is facilitated.
Detailed Description
The present invention will be described in detail with reference to specific examples.
The embodiment of the invention provides a cobalt-containing phosphating agent for surface pretreatment of a metal piece, which comprises the following components in parts by weight in 1000 parts: 5-30 parts of phosphoric acid, 3-10 parts of zinc oxide, 0.5-3 parts of magnesium salt, 0.5-3 parts of aluminum salt, 0.5-5 parts of cobalt nitrate and the balance of water.
Specifically, the phosphating agent also comprises 0.2-3 parts of nickel nitrate, 0.2-2 parts of nitric acid and 0.5-5 parts of tannic acid. The weight parts of the cobalt nitrate are 1-3 parts, the weight parts of the nickel nitrate are 0.5-2 parts, and the weight parts of the tannic acid are 1-3 parts. The purity of the phosphoric acid is not less than 85%, and the weight portion of the phosphoric acid is preferably 10-20 parts. The magnesium salt is magnesium nitrate and magnesium sulfate, the aluminum salt is aluminum nitrate and aluminum sulfate, and the zinc oxide is 5-8 parts by weight.
In the phosphating agent, the better film forming effect is achieved by controlling the proportion balance of the components. For example, when the content of phosphoric acid is low, the film formation is too slow and too thin, and even the film formation cannot be performed, on the contrary, the film formation is too fast due to too fast reaction, the film just formed is dissolved again, and the film is not firm enough, so that the weight part of phosphoric acid is preferably 10 to 20 in this embodiment. Among them, zinc oxide and phosphoric acid function to provide the main components of the phosphating film. The cobalt nitrate is used as an accelerant and a secondary component of the film layer, and the cobalt nitrate can accelerate the film layer forming speed and improve the film layer adhesive force during film forming. The nickel nitrate is used for improving the corrosion resistance of the film, and magnesium nitrate, aluminum nitrate and other magnesium salts or aluminum salts obviously improve the compactness, the corrosion resistance and the adhesive force of the film.
In the embodiment, the phosphating layer formed by the phosphating agent has a delicate structure, firm adhesion, good corrosion resistance, capability of resisting high temperature of 280 ℃, no damage caused by baking at the high temperature of 280 ℃, low energy consumption and simple operation, and can be used for phosphating before spraying on the surface of steel.
The embodiment of the invention also provides a metal piece surface phosphating method, which comprises the following steps: preparing the phosphating agent, forming phosphating agent solution, brushing, soaking and spraying the phosphating agent solution on the metal piece, performing treatment for a preset time, washing the metal piece with water, and drying.
When the metal piece is immersed into the phosphating agent solution for surface treatment, the temperature of the phosphating agent is controlled to be 10-50 ℃, and is preferably controlled to be about 35 ℃. The metal part is preferably immersed in the phosphating solution for a period of 5 to 15 minutes. The embodiment of the invention also provides a metal piece, which is treated by the metal piece surface phosphating method, so that phosphating is formed on the surface of the metal piece. After the metal piece is brushed, soaked and sprayed with the phosphating agent solution, a phosphating layer formed on the surface is compact in structure and strong in adhesive force, and a subsequent spraying process is facilitated, so that the adhesion formation of a coating is facilitated. Moreover, the metal part is protected by phosphorization, and the color and luster are bright.
The phosphating agent, the treatment method thereof, the formed metal piece performance and other aspects of the invention are described by specific examples.
Example 1
Mixing the following components in parts by weight (the total amount is 1000 parts by weight): 5 parts of phosphoric acid, 3 parts of zinc oxide, 0.5 part of magnesium nitrate, 0.5 part of aluminum nitrate, 0.5 part of cobalt nitrate and the balance of water, and stirring and uniformly mixing to prepare the phosphating agent.
The treatment method comprises the following steps: preparing a phosphating agent solution; taking a cold-rolled sheet as an example of the metal piece, immersing the cold-rolled sheet into a phosphating agent solution, controlling the temperature at 35 ℃, performing soaking treatment for 10 minutes, washing the metal piece with water, and drying. In the treatment process, a phosphating agent can be added in time to ensure the effect of the working solution. The temperature for phosphorization drying should not be too high, and should be controlled at normal temperature to 120 deg.C to prevent film layer from cracking due to too high temperature.
After the phosphating agent solution is treated, the surface of the metal workpiece is observed, the surface of the workpiece is colored, uniform in color and fine in phosphating, and the adhesion is evaluated to grade 1 according to a 2-hour boiling water adhesion test after spraying treatment.
Example 2
Mixing the following components in parts by weight (the total amount is 1000 parts by weight): 10 parts of phosphoric acid, 5 parts of zinc oxide, 1 part of magnesium nitrate, 1 part of cobalt nitrate, 0.2 part of nickel nitrate, 0.5 part of tannic acid and the balance of water, and stirring and uniformly mixing to prepare the phosphating agent.
The treatment method comprises the following steps: preparing a phosphating agent solution; taking a cold-rolled sheet as an example of the metal piece, immersing the cold-rolled sheet into a phosphating agent solution, controlling the temperature at 35 ℃, performing soaking treatment for 10 minutes, washing the metal piece with water, and drying. In the treatment process, a phosphating agent can be added in time to ensure the effect of the working solution. The temperature for phosphorization drying should not be too high, and should be controlled at normal temperature to 120 deg.C to prevent film layer from cracking due to too high temperature.
After the phosphating agent solution is treated, the surface of the metal workpiece is observed, the surface of the workpiece is colored, uniform in color and fine in phosphating, and the adhesion is evaluated to be 0 grade according to a 2-hour boiling water adhesion test after spraying treatment.
Example 3
Mixing the following components in parts by weight (the total amount is 1000 parts by weight): 20 parts of phosphoric acid, 8 parts of zinc oxide, 2 parts of magnesium nitrate, 1 part of aluminum nitrate, 2 parts of cobalt nitrate, 1 part of nickel nitrate, 1 part of tannic acid and the balance of water, and stirring and uniformly mixing to prepare the phosphating agent.
The treatment method comprises the following steps: preparing a phosphating agent solution; taking a cold-rolled sheet as an example of the metal piece, immersing the cold-rolled sheet into a phosphating agent solution, controlling the temperature at 35 ℃, performing soaking treatment for 10 minutes, washing the metal piece with water, and drying. In the treatment process, a phosphating agent can be added in time to ensure the effect of the working solution. The temperature for phosphorization drying should not be too high, and should be controlled at normal temperature to 120 deg.C to prevent film layer from cracking due to too high temperature.
After the phosphating agent solution is treated, the surface of the metal workpiece is observed, the surface of the workpiece is colored, uniform in color and fine in phosphating, and the adhesion is evaluated to be 0 grade according to a 2-hour boiling water adhesion test after spraying treatment.
Example 4
Mixing the following components in parts by weight (the total amount is 1000 parts by weight): 25 parts of phosphoric acid, 9 parts of zinc oxide, 2 parts of magnesium nitrate, 2 parts of aluminum nitrate, 3 parts of cobalt nitrate, 2 parts of nickel nitrate, 3 parts of tannic acid and the balance of water, and stirring and uniformly mixing the components to prepare the phosphating agent.
The treatment method comprises the following steps: preparing a phosphating agent solution; taking a cold-rolled sheet as an example of the metal piece, immersing the cold-rolled sheet into a phosphating agent solution, controlling the temperature at 35 ℃, performing soaking treatment for 10 minutes, washing the metal piece with water, and drying. In the treatment process, a phosphating agent can be added in time to ensure the effect of the working solution. The temperature for phosphorization drying should not be too high, and should be controlled at normal temperature to 120 deg.C to prevent film layer from cracking due to too high temperature.
After the phosphating agent solution is treated, the surface of the metal workpiece is observed, the surface of the workpiece is colored, uniform in color and fine in phosphating, and the adhesion is evaluated to be 0 grade according to a 2-hour boiling water adhesion test after spraying treatment.
Example 5
Mixing the following components in parts by weight (the total amount is 1000 parts by weight): 30 parts of phosphoric acid, 10 parts of zinc oxide, 3 parts of magnesium nitrate, 1 part of aluminum nitrate, 5 parts of cobalt nitrate, 3 parts of nickel nitrate, 1 part of nitric acid, 5 parts of tannic acid and the balance of water, and stirring and uniformly mixing to prepare the phosphating agent.
The treatment method comprises the following steps: preparing a phosphating agent solution; taking a cold-rolled sheet as an example of the metal piece, immersing the cold-rolled sheet into a phosphating agent solution, controlling the temperature at 35 ℃, performing soaking treatment for 10 minutes, washing the metal piece with water, and drying. In the treatment process, a phosphating agent can be added in time to ensure the effect of the working solution. The temperature for phosphorization drying should not be too high, and should be controlled at normal temperature to 120 deg.C to prevent film layer from cracking due to too high temperature.
After the phosphating agent solution is treated, the surface of the metal workpiece is observed, the surface of the workpiece is colored, uniform in color and fine in phosphating, and the adhesion is evaluated to be 0 grade according to a 2-hour boiling water adhesion test after spraying treatment.
It should be noted that the present invention is not limited to the above-mentioned embodiments, and other changes and modifications can be made by those skilled in the art according to the spirit of the present invention, and these changes and modifications made according to the spirit of the present invention should be included in the scope of the present invention as claimed.
Claims (10)
1. A phosphating agent is used for forming phosphating on the surface of a metal piece and is characterized by comprising the following components in parts by weight in 1000 parts by weight: 5-30 parts of phosphoric acid, 3-10 parts of zinc oxide, 0.5-3 parts of magnesium salt, 0.5-3 parts of aluminum salt, 0.5-5 parts of cobalt nitrate and the balance of water.
2. The phosphating agent of claim 1 further comprising 0.2 to 3 parts nickel nitrate, 0.2 to 2 parts nitric acid and 0.5 to 5 parts tannic acid.
3. The phosphating agent of claim 1, wherein the phosphoric acid has a purity of 85% or greater.
4. The phosphating agent of claim 1 wherein the magnesium salt is magnesium nitrate or magnesium sulfate and the aluminum salt is aluminum nitrate or aluminum sulfate.
5. The phosphating agent of claim 1, wherein the phosphoric acid is present in an amount of from 10 to 20 parts by weight.
6. The phosphating agent of claim 1, wherein the zinc oxide is present in an amount of 5 to 8 parts by weight.
7. The phosphating agent of claim 2, wherein the cobalt nitrate is 1 to 3 parts by weight, the nickel nitrate is 0.5 to 2 parts by weight, and the tannic acid is 1 to 3 parts by weight.
8. A surface phosphating method for a metal piece comprises the following steps: preparing a phosphating agent according to any one of claims 1 to 7, forming a phosphating agent solution, brushing, dipping and spraying the phosphating agent solution on a metal piece, washing the metal piece with water after a predetermined time, and drying.
9. A metal member characterized in that a surface of the metal member is formed with a phosphate coating by the metal member surface phosphating method according to claim 8.
10. The metal article of claim 9, wherein the metal article is a cold rolled sheet, a hot rolled sheet, or an angle steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011458271.3A CN112725786A (en) | 2020-12-11 | 2020-12-11 | Cobalt-containing phosphating agent, metal piece and surface phosphating method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011458271.3A CN112725786A (en) | 2020-12-11 | 2020-12-11 | Cobalt-containing phosphating agent, metal piece and surface phosphating method thereof |
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| Publication Number | Publication Date |
|---|---|
| CN112725786A true CN112725786A (en) | 2021-04-30 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011458271.3A Withdrawn CN112725786A (en) | 2020-12-11 | 2020-12-11 | Cobalt-containing phosphating agent, metal piece and surface phosphating method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116024559A (en) * | 2022-12-31 | 2023-04-28 | 广东斗原精密技术有限公司 | Coating agent and steel processing method |
-
2020
- 2020-12-11 CN CN202011458271.3A patent/CN112725786A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116024559A (en) * | 2022-12-31 | 2023-04-28 | 广东斗原精密技术有限公司 | Coating agent and steel processing method |
| CN116024559B (en) * | 2022-12-31 | 2023-11-07 | 广东斗原精密技术有限公司 | Coating agent and steel processing method |
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Application publication date: 20210430 |
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