CN108930045B - Copper alloy cleaning method - Google Patents
Copper alloy cleaning method Download PDFInfo
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- CN108930045B CN108930045B CN201810791575.8A CN201810791575A CN108930045B CN 108930045 B CN108930045 B CN 108930045B CN 201810791575 A CN201810791575 A CN 201810791575A CN 108930045 B CN108930045 B CN 108930045B
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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
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/10—Other heavy metals
- C23G1/103—Other heavy metals copper or alloys of copper
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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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F17/00—Multi-step processes for surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by subclass C21D or C22F or class C25
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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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F3/00—Brightening metals by chemical means
- C23F3/04—Heavy metals
- C23F3/06—Heavy metals with acidic solutions
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- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- ing And Chemical Polishing (AREA)
- Cleaning Or Drying Semiconductors (AREA)
Abstract
The invention belongs to the technical field of copper alloy surface treatment, and discloses a copper alloy cleaning method, which comprises the following steps: step one, acid washing: soaking and washing the copper alloy in a pickling solution, and then taking out and washing; step two, light emitting: soaking and washing the copper alloy obtained in the step one in a brightening solution, and then taking out and washing; step three, demoulding: soaking and washing the copper alloy obtained in the step two in a stripping liquid, and then taking out and washing; the copper alloy cleaning method is completely free of chromium, phosphorus, heavy metals and toxic and harmful chemical substances, the wastewater treatment process is simple, the wastewater treatment chemicals mainly adopt cheap quick lime, caustic soda and a small amount of flocculant, and the wastewater treatment cost is very low compared with that of high-concentration chromium-containing wastewater.
Description
Technical Field
The invention belongs to the technical field of copper alloy surface treatment, and particularly relates to a copper alloy cleaning method.
Background
In the field of copper alloy wire manufacturing, waste water generated after chromic acid cleaning and passivation and filtered chromium slag are a great harmful source and a potential hazard source for natural ecological environment all the time, and the common chromium-free cleaning technology process on the market has the limitations of difficult operation and difficult control in practice such as fast bath solution temperature rise, unstable bath solution, even cooling facilities and the like, and simultaneously, the cleaning cost is difficult to control, so the environment-friendly chromium-free cleaning technology process replacing chromic acid cleaning passivation and low cost becomes the technical problem which is to be solved by the whole field of copper alloy wire manufacturing.
Disclosure of Invention
In order to solve the above problems in the prior art, the present invention aims to provide a method for cleaning copper alloy.
The technical scheme adopted by the invention is as follows:
a copper alloy cleaning method comprises the following steps:
step one, acid washing: soaking and washing the copper alloy in a pickling solution, and then taking out and washing; the pickling solution comprises 5-15% of industrial sulfuric acid, 5-15% of 50% of hydrogen peroxide, 0.1-1% of glacial acetic acid and the balance of water by mass percent;
in the process, the hydrogen peroxide is used for replacing the combination of nitric acid and industrial sulfuric acid which are strong oxidizers and can generate toxic smoke in the prior art, the oxide on the surface of the copper alloy is rapidly stripped, and the copper alloy oxide is converted into copper sulfate crystal for precipitation.
Step two, light emitting: soaking and washing the copper alloy obtained in the step one in a brightening solution, and then taking out and washing; the brightening liquid comprises 4-99.9% of hydrogen peroxide, 0.1-0.6% of industrial sulfuric acid and 0-7% of ethanol with the mass percentage of 50%, and the balance of water;
after the copper alloy is washed by acid washing, stripping and flushing oxide on the surface, the surface of the copper alloy has no good metallic luster because of uneven corrosion, so that the bright state of the surface of the copper alloy can be achieved by carrying out mild chemical polishing in the step two; the ethanol is used as a stabilizer in the process, so that the service life of the brightening liquid is prolonged from about 4 days to about 7 days.
Step three, demoulding: soaking and washing the copper alloy obtained in the step two in a stripping liquid, and then taking out and washing; the stripping liquid comprises 1-100% of glacial acetic acid by mass percent and the balance of water.
After the copper alloy is washed by light-emitting and water-flushing, a layer of golden yellow copper alloy oxide film is formed on the surface of the copper alloy, and the golden yellow copper alloy oxide film needs to be removed in glacial acetic acid aqueous solution, so that the original metallic luster of the copper alloy can be shown.
Preferably, the copper alloy cleaning method further comprises:
step four, passivation: and (4) passivating the copper alloy obtained in the third step in a passivating solution, and then taking out and cleaning the copper alloy.
After the copper alloy is subjected to demoulding, in order to enhance the oxidation resistance of the copper alloy in the subsequent packaging and storage processes, after the copper alloy is washed by water, the copper alloy needs to be subjected to oxidation resistance treatment through passivation. Wherein, the passivation solution is the prior art.
Preferably, the copper alloy cleaning method further comprises:
step five, drying: and (4) soaking the copper alloy obtained in the fourth step in hot water, taking out and air-drying.
After the copper alloy is subjected to passivation and oxidation resistance treatment, for quick drying, the copper alloy can be soaked and washed in hot water at the temperature of 60-90 ℃ for 5-10 seconds, then surface moisture is quickly evaporated, and packaging can be carried out after drying.
Preferably, the pickling solution in the step one is prepared by mixing 8-10% of industrial sulfuric acid with the mass percentage of 98%, 8-10% of 50% of hydrogen peroxide and 0.1-1% of glacial acetic acid with water to 100%.
Preferably, the immersion cleaning time in the step one is 10 to 60 seconds, and the immersion cleaning temperature is normal temperature.
Preferably, the brightening solution in the second step is prepared by mixing 10-20% of hydrogen peroxide and 0.25-0.4% of industrial sulfuric acid in percentage by mass, wherein the hydrogen peroxide is 50%, and the industrial sulfuric acid is 98%, and the water is added to 100%.
Preferably, the immersion cleaning time in the second step is 10 to 60 seconds, and the immersion cleaning temperature is normal temperature.
Preferably, the membrane removing liquid in the third step is prepared by adding water to 100% according to the mass percentage of glacial acetic acid of 10-20%.
Preferably, the immersion cleaning time in the third step is 10-60 seconds, and the immersion cleaning temperature is normal temperature.
The above washing is sufficient water washing.
The invention has the beneficial effects that:
the copper alloy cleaning method provided by the invention has the advantages that the tank liquor of each working procedure section does not contain lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls and polybrominated phenylene oxides, does not contain extremely toxic and harmful chemical substances such as phosphorus and derivatives thereof, the main components of the tank liquor are hydrogen peroxide, a small amount of hydrocarbon and trace carbon, hydrogen, oxygen and nitrogen compounds, the tank liquor is easily decomposed into oxygen and water and is easily biodegraded under the alkalescent state, so the generated wastewater is mainly combined with quicklime and caustic soda to adjust the pH value to be neutral, copper sulfate crystals in the tank liquor are filtered, the formed clear liquid is easily purified to the discharge standard, the uncleanness of chromium-containing wastewater treatment and the damage and potential harm of chromium slag to water and soil in the natural environment are completely avoided, the copper alloy cleaning method is completely free of chromium, phosphorus, heavy metals and toxic and harmful chemical substances, the wastewater treatment process is simple, and the wastewater treatment chemical mainly adopts cheap quicklime, The treatment cost of the waste water is very low compared with the treatment cost of the high-concentration chromium-containing waste water.
Drawings
FIG. 1 is a flow chart of the copper alloy cleaning method of the present invention.
FIG. 2 is a process diagram of wastewater treatment according to the present invention.
Detailed Description
The invention is further explained below with reference to the drawings and the specific embodiments.
Example 1:
as shown in fig. 1, the present embodiment provides a copper alloy cleaning method for cleaning a copper alloy wire, including the following steps:
step one, acid washing: the copper alloy wire is soaked and washed for 50 seconds in pickling solution prepared by mixing 98% of industrial sulfuric acid 9%, 50% of hydrogen peroxide 9% and glacial acetic acid 0.6% by mass and adding water to 100%, and then the copper alloy wire is taken out and washed, wherein the soaking and washing temperature is normal temperature.
Step two, light emitting: and (3) soaking and washing the copper alloy wire rod obtained in the step one in a bright dipping solution prepared by mixing 15% of hydrogen peroxide and 0.3% of industrial sulfuric acid in a mass percentage of 50% and adding water to 100%, taking out and washing, wherein the soaking and washing temperature is normal temperature.
Step three, demoulding: and (3) soaking and washing the copper alloy wire rod obtained in the step two in a stripping liquid prepared by mixing 10% of glacial acetic acid by mass and adding water to 100% by mass for 50 seconds, then taking out and washing, wherein the soaking and washing temperature is normal temperature.
Step four, passivation: and (4) passivating the copper alloy wire rod obtained in the third step in a passivating solution for 50 seconds, and then taking out and cleaning the copper alloy wire rod.
Step five, drying: and (4) soaking and washing the copper alloy wire rod obtained in the fourth step in hot water at 85 ℃ for 8 seconds, taking out and air-drying the copper alloy wire rod, and packaging the copper alloy wire rod after drying.
Example 2:
as shown in fig. 1, the present embodiment provides a method for cleaning a copper alloy, including the following steps:
step one, acid washing: the copper alloy is soaked and washed for 60 seconds in pickling solution prepared by mixing 98% of industrial sulfuric acid 5%, 50% of hydrogen peroxide 5% and glacial acetic acid 0.1% by mass and adding water to 100%, and then the copper alloy is taken out and washed, wherein the soaking and washing temperature is normal temperature.
Step two, light emitting: and (3) soaking and washing the copper alloy obtained in the step one in a bright dipping solution prepared by mixing 4% of 50% hydrogen peroxide, 0.1% of 98% industrial sulfuric acid and 7% of 95% ethanol in percentage by mass with water to 100% for 60 seconds, then taking out and washing, wherein the soaking and washing temperature is normal temperature.
Step three, demoulding: and (3) soaking and washing the copper alloy obtained in the step two in a stripping liquid prepared by mixing 1% of glacial acetic acid by mass and adding water to 100% by mass for 60 seconds, then taking out and washing, wherein the soaking and washing temperature is normal temperature.
Step four, passivation: and (4) passivating the copper alloy obtained in the third step in a passivating solution for 20 seconds, and then taking out and cleaning the copper alloy.
Step five, drying: and (4) soaking and washing the copper alloy obtained in the fourth step in hot water at 90 ℃ for 10 seconds, taking out and air-drying the copper alloy, and packaging the copper alloy after drying.
Example 3:
as shown in fig. 1, the present embodiment provides a method for cleaning a copper alloy, including the following steps:
step one, acid washing: the copper alloy is soaked and washed in pickling solution prepared by mixing 98% of industrial sulfuric acid 15%, 50% of hydrogen peroxide 15% and glacial acetic acid 1% by mass and adding water to 100% for 20 seconds, and then taken out and washed, wherein the soaking and washing temperature is normal temperature.
Step two, light emitting: and (3) soaking and washing the copper alloy obtained in the step one in a bright dipping solution prepared by mixing 99.4% of hydrogen peroxide and 0.6% of industrial sulfuric acid, wherein the hydrogen peroxide and the industrial sulfuric acid are 50% by mass for 25 seconds, and then taking out and washing the copper alloy, wherein the soaking and washing temperature is normal temperature.
Step three, demoulding: and D, soaking and washing the copper alloy obtained in the step two in a stripping liquid prepared from 100% of glacial acetic acid by mass for 20 seconds, then taking out and washing, wherein the soaking and washing temperature is normal temperature.
Step four, passivation: and (4) passivating the copper alloy obtained in the third step in a passivating solution for 30 seconds, and then taking out and cleaning the copper alloy.
Step five, drying: and (4) soaking and washing the copper alloy obtained in the fourth step in hot water at 60 ℃ for 6 seconds, taking out and air-drying the copper alloy, and packaging the copper alloy after drying.
Example 4:
as shown in fig. 1, the present embodiment provides a copper alloy cleaning method for cleaning a copper alloy wire, including the following steps:
step one, acid washing: the copper alloy wire is soaked and washed for 35 seconds in pickling solution prepared by mixing 98% of industrial sulfuric acid 10%, 50% of hydrogen peroxide 10% and glacial acetic acid 0.6% by mass and adding water to 100%, and then the copper alloy wire is taken out and washed, wherein the soaking and washing temperature is normal temperature.
Step two, light emitting: and (3) soaking and washing the copper alloy wire rod obtained in the step one in a bright dipping solution prepared by mixing 55% of hydrogen peroxide, 0.3% of 98% of industrial sulfuric acid and 5% of 95% of ethanol in percentage by mass and adding water to 100% for 35 seconds, and then taking out and washing the copper alloy wire rod, wherein the soaking and washing temperature is normal temperature.
Step three, demoulding: and (3) soaking and washing the copper alloy wire rod obtained in the step two in a stripping liquid prepared by mixing 55% of glacial acetic acid and 100% of water by mass for 35 seconds, taking out and washing, wherein the soaking and washing temperature is normal temperature.
Step four, passivation: and (4) passivating the copper alloy wire rod obtained in the third step in a passivating solution for 35 seconds, and then taking out and cleaning the copper alloy wire rod.
Step five, drying: and (4) soaking and washing the copper alloy wire rod obtained in the fourth step in hot water at 70 ℃ for 8 seconds, taking out and air-drying the copper alloy wire rod, and packaging the copper alloy wire rod after drying.
The present invention is not limited to the above-described alternative embodiments, and various other forms of products can be obtained by anyone in light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.
Claims (9)
1. A copper alloy cleaning method is characterized by comprising the following steps:
step one, acid washing: soaking and washing the copper alloy in a pickling solution, and then taking out and washing; the pickling solution comprises 5-15% of industrial sulfuric acid, 5-15% of 50% of hydrogen peroxide, 0.1-1% of glacial acetic acid and the balance of water by mass percent;
step two, light emitting: soaking and washing the copper alloy obtained in the step one in a brightening solution, and then taking out and washing; the brightening liquid comprises 4-99.9% of hydrogen peroxide, 0.1-0.6% of industrial sulfuric acid and 0-7% of ethanol with the mass percentage of 50%, and the balance of water;
step three, demoulding: soaking and washing the copper alloy obtained in the step two in a stripping liquid, and then taking out and washing; the stripping liquid comprises 1-100% of glacial acetic acid by mass percent and the balance of water.
2. The method for cleaning a copper alloy according to claim 1, wherein: the copper alloy cleaning method further comprises the following steps:
step four, passivation: and (4) passivating the copper alloy obtained in the third step in a passivating solution, and then taking out and cleaning the copper alloy.
3. The method for cleaning a copper alloy according to claim 2, wherein: the copper alloy cleaning method further comprises the following steps:
step five, drying: and (4) soaking the copper alloy obtained in the fourth step in hot water, taking out and air-drying.
4. The method for cleaning a copper alloy according to claim 1, wherein: the pickling solution in the first step is prepared by mixing 8-10% of industrial sulfuric acid with the mass percent of 98%, 8-10% of 50% of hydrogen peroxide and 0.1-1% of glacial acetic acid with water until the mixture is 100%.
5. The copper alloy cleaning method according to claim 1 or 4, characterized in that: the immersion cleaning time in the step one is 10-60 seconds, and the immersion cleaning temperature is normal temperature.
6. The method for cleaning a copper alloy according to claim 1, wherein: the light emitting liquid in the step two is prepared by mixing 10-20% of hydrogen peroxide with the mass percentage of 50% and 0.25-0.4% of industrial sulfuric acid with water to 100%.
7. The copper alloy cleaning method according to claim 1 or 6, characterized in that: and the immersion cleaning time in the second step is 10-60 seconds, and the immersion cleaning temperature is normal temperature.
8. The method for cleaning a copper alloy according to claim 1, wherein: the film removing liquid in the third step is prepared by adding water to 100% according to the mass percentage of glacial acetic acid of 10-20%.
9. The copper alloy cleaning method according to claim 1 or 8, characterized in that: the immersion cleaning time in the third step is 10-60 seconds, and the immersion cleaning temperature is normal temperature.
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| CN111763936A (en) * | 2020-07-07 | 2020-10-13 | 苏州市吴中区曙光铜管厂 | Pre-passivation treatment process for inner wall of seamless smooth copper pipe |
| CN115110085A (en) * | 2021-10-23 | 2022-09-27 | 赵晓峰 | Novel method for improving stripping process in copper and alloy hydrogen peroxide chemical polishing system |
| CN115852383B (en) * | 2022-11-25 | 2024-08-13 | 国网浙江省电力有限公司宁波供电公司 | Copper alloy wire surface treatment equipment |
| CN119287357A (en) * | 2024-12-10 | 2025-01-10 | 湖南旺坤管业有限公司 | A pickling and passivation process for stainless steel pipe fittings |
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| DD104323A5 (en) * | 1973-04-25 | 1974-03-05 | ||
| CN101235507A (en) * | 2007-02-02 | 2008-08-06 | 深圳富泰宏精密工业有限公司 | Technique for cleaning beryllium-copper alloy |
| CN102051620A (en) * | 2010-11-24 | 2011-05-11 | 温州奥洋金属表面处理有限公司 | A kind of polishing solution for treating copper and copper alloy surface which replaces copper pickling process |
| CN103849876B (en) * | 2012-12-03 | 2016-04-06 | 浙江伟星实业发展股份有限公司 | A kind of chemically polishing method |
| CN106676538A (en) * | 2017-01-18 | 2017-05-17 | 宁波金田铜业(集团)股份有限公司 | Environment-friendly technology for copper and copper alloy surface treatment |
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