CN112458447A - Method for coloring silver oxide gray at constant temperature of copper alloy - Google Patents

Method for coloring silver oxide gray at constant temperature of copper alloy Download PDF

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Publication number
CN112458447A
CN112458447A CN202011373231.9A CN202011373231A CN112458447A CN 112458447 A CN112458447 A CN 112458447A CN 202011373231 A CN202011373231 A CN 202011373231A CN 112458447 A CN112458447 A CN 112458447A
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China
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copper alloy
coloring
liquid
solution
stirring
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Pending
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CN202011373231.9A
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Chinese (zh)
Inventor
王宏
丁峰
徐春红
芦斌
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China Aviation Industry Standard Parts Manufacturing Co Ltd
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China Aviation Industry Standard Parts Manufacturing Co Ltd
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Priority to CN202011373231.9A priority Critical patent/CN112458447A/en
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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
    • C23C22/52—Treatment of copper or alloys based thereon
    • 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
    • C23C22/78—Pretreatment of the material to be coated
    • 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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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Treatment Of Metals (AREA)

Abstract

The invention discloses a method for coloring silver oxide gray at constant temperature of copper alloy, which is characterized by comprising the following steps of: (1) preparing a coloring liquid: stirring and dissolving lead carbonate, acetic acid and sodium thiosulfate and standing to obtain a coloring liquid; (2) copper alloy pretreatment: firstly, placing copper alloy in degreasing liquid for ultrasonic degreasing, then preparing polishing liquid, chemically polishing the copper alloy for 5-15s, then taking out and cleaning, and then activating for 30-60s by means of sulfuric acid activating liquid; (3) heating the coloring liquid prepared in the step (1) to 80 ℃ and keeping the temperature constant, immersing the copper alloy treated in the step (2) into the coloring liquid and slowly stirring, soaking for 50-60s to realize silver gray coloring, then taking out the copper alloy, washing with clear water and drying, and protecting by using wax. The invention has the advantages of convenient operation, high efficiency, reliability, good effect and simple formula, and is suitable for popularization and application of constant-temperature silver oxide gray coloring of copper alloy.

Description

Method for coloring silver oxide gray at constant temperature of copper alloy
Technical Field
The invention belongs to the technical field of surface treatment, and particularly relates to a method for coloring silver oxide gray at constant temperature of copper alloy.
Background
The basic principle of the coloring process is that a layer of very thin compound is formed on the surface of copper and its alloy by chemical oxidation or anode electrolysis or cathode electrolysis, thereby producing various shades of color including yellow, orange, red, purple, blue, green, black, cyan, bronze, etc., but the electrolysis process needs to consume a large amount of electric energy and needs large-scale equipment. In the prior art, various coloring processes exist, but a plurality of problems exist: the formula components are complex, the required coloring treatment time is long, the coloring effect is poor, a film layer is easy to fall off, the service life of the coloring liquid is short, and the coloring thickness is uneven.
Disclosure of Invention
The invention aims to overcome the defects and provide the method for coloring the copper alloy constant-temperature silver oxide gray, which is convenient to operate, efficient, reliable, good in effect and simple in formula.
The purpose of the invention and the main technical problem of solving the invention are realized by adopting the following technical scheme:
the invention discloses a method for coloring silver oxide gray at constant temperature of copper alloy, which comprises the following steps:
(1) preparing a coloring liquid: weighing 15-20g of lead carbonate, placing the lead carbonate in a beaker with the capacity of 1L, adding 200mL of deionized water, stirring and dissolving, weighing 35-40mL of acetic acid, slowly stirring and adding the acetic acid into the solution, standing the solution for 30min, weighing 45-60g of sodium thiosulfate, adding the sodium thiosulfate into the standing solution, stirring and dissolving, and standing for 60min to obtain a coloring solution;
(2) copper alloy pretreatment: firstly, measuring 40-60g of oil powder LCX-52 (industrial grade), adding water to dilute the oil powder LCX-52 to 1L, heating the oil powder LCX-52 to 50-60 ℃, then placing the copper alloy in deoiling liquid to carry out ultrasonic deoiling, taking out the oil powder after 30-60s, washing the oil powder with deionized water, then weighing 90-120g of chromic anhydride and 10-15mL of sulfuric acid, adding water to dilute the copper alloy to 1L, uniformly stirring the mixture to prepare polishing solution, taking out the copper alloy after chemical polishing for 5-15s, washing the copper alloy, then preparing 20-50mL/L of sulfuric acid as activating solution, taking out the copper alloy after activating the copper alloy for 30-60s at room temperature;
(3) coloring: heating the coloring liquid prepared in the step (1) to 80 ℃ and keeping the temperature constant, immersing the copper alloy treated in the step (2) into the coloring liquid and slowly stirring, soaking for 50-60s to realize silver gray coloring, then taking out the copper alloy, washing with clear water and drying, and protecting by using wax.
Compared with the prior art, the invention has obvious advantages and beneficial effects. According to the technical scheme, in the method for coloring the grey silver oxide at the constant temperature of the copper alloy, the lead carbonate, the sodium thiosulfate and the acetic acid are added into the coloring liquid formula, the compactness and the film forming rate of the film layer are improved due to the addition of the lead carbonate, the acetic acid can adjust the pH =4 of the coloring liquid to enable the film layer to be more compact, the synergistic interaction effect is achieved with the added lead carbonate, the brightness can be improved, the stability and the corrosion resistance of the coloring layer are improved, and the uniformity and the attractiveness of the appearance color are guaranteed. S ionized by sodium thiosulfate2O3 2-And S2-With metal ions Pb2+Black sulfide particles are formed and attached on the surface of copper or copper alloy to form a bottom color, and the color is increased from silver gray to lake blue to silver gray along with the red color of the copper alloy. The extent of the chemical reaction varies with the reaction time, and the resulting color of the mixture varies, which may be determined by a variety of factors, including grain size, interference of light, etc. In a word, the invention has the advantages of convenient operation, high efficiency, reliability, good effect and simple formula, and is suitable for popularization and application of the constant-temperature silver oxide gray coloring of the copper alloy.
Detailed Description
The following preferred embodiments, detailed descriptions of the specific implementation, structure, features and effects of the method for coloring silver oxide gray at constant temperature for copper alloy according to the present invention are provided below.
Example 1:
the method for coloring the silver gray oxide at constant temperature of the copper alloy is characterized by comprising the following steps of:
(1) preparing a coloring liquid: weighing 15g of lead carbonate, placing the lead carbonate in a beaker with the capacity of 1L, adding 200mL of deionized water, stirring and dissolving, weighing 35mL of acetic acid, slowly stirring and adding the acetic acid into the solution, standing the solution for 30min, weighing 45g of sodium thiosulfate, adding the sodium thiosulfate into the solution after standing, stirring and dissolving the sodium thiosulfate, and standing for 60min to obtain a coloring solution;
(2) copper alloy pretreatment: firstly, 40g of oil powder LCX-52 (industrial grade) is measured, water is added to dilute the oil powder LCX-52 to 1L, the copper alloy is placed in deoiling liquid to carry out ultrasonic deoiling after being heated to 50 ℃, the copper alloy is taken out after 30s and cleaned by deionized water, 90g of chromic anhydride and 10mL of sulfuric acid are weighed, water is added to dilute the copper alloy to 1L and then stirred uniformly to prepare polishing solution, the copper alloy is taken out after being chemically polished for 5s and cleaned, then 20mL/L of sulfuric acid is prepared to be used as activating solution, and the copper alloy is taken out and cleaned after being activated for 30s at room;
(3) coloring: heating the coloring liquid prepared in the step (1) to 80 ℃ and keeping the temperature constant, immersing the copper alloy treated in the step (2) into the coloring liquid and slowly stirring, soaking for 50s to realize silver gray coloring, then taking out the copper alloy, cleaning with clear water and drying, and protecting by using wax.
Example 2:
the method for coloring the silver gray oxide at constant temperature of the copper alloy is characterized by comprising the following steps of:
(1) preparing a coloring liquid: weighing 17.5g of lead carbonate, placing the lead carbonate in a beaker with the capacity of 1L, adding 200mL of deionized water, stirring and dissolving, weighing 37.5mL of acetic acid, slowly stirring and adding the acetic acid into the solution, standing the solution for 30min, weighing 52.5g of sodium thiosulfate, adding the sodium thiosulfate into the standing solution, stirring and dissolving, and standing for 60min to obtain a coloring solution;
(2) copper alloy pretreatment: firstly, 50g of oil powder LCX-52 (industrial grade) is measured, water is added to dilute the oil powder LCX-52 to 1L, the copper alloy is placed in deoiling liquid to carry out ultrasonic deoiling after being heated to 55 ℃, the oil powder is taken out after 45s and cleaned by deionized water, 105g of chromic anhydride and 12.5mL of sulfuric acid are weighed, water is added to dilute the oil alloy to 1L and stirred uniformly to prepare polishing solution, the copper alloy is taken out after being chemically polished for 10s and cleaned, then 35mL/L of sulfuric acid is prepared to be used as activating solution, and the copper alloy is taken out after being activated for 45s at room temperature and cleaned;
(3) coloring: heating the coloring liquid prepared in the step (1) to 80 ℃ and keeping the temperature constant, immersing the copper alloy treated in the step (2) into the coloring liquid and slowly stirring, soaking for 55s to realize silver gray coloring, then taking out the copper alloy, cleaning with clear water and drying, and protecting by using wax.
Example 3:
the method for coloring the silver gray oxide at constant temperature of the copper alloy is characterized by comprising the following steps of:
(1) preparing a coloring liquid: weighing 20g of lead carbonate, placing the lead carbonate in a beaker with the capacity of 1L, adding 200mL of deionized water, stirring and dissolving, weighing 40mL of acetic acid, slowly stirring and adding the acetic acid into the solution, standing the solution for 30min, weighing 60g of sodium thiosulfate, adding the sodium thiosulfate into the solution after standing, stirring and dissolving the sodium thiosulfate, and standing for 60min to obtain a coloring solution;
(2) copper alloy pretreatment: firstly, 60g of oil powder LCX-52 (industrial grade) is measured, water is added to dilute the oil powder LCX-52 to 1L, the copper alloy is placed in deoiling liquid to carry out ultrasonic deoiling after the temperature is heated to 60 ℃, the oil powder is taken out after 60s and cleaned by deionized water, 120g of chromic anhydride and 15mL of sulfuric acid are weighed, water is added to dilute the oil alloy to 1L and stirred uniformly to prepare polishing solution, the copper alloy is taken out after being chemically polished for 15s and cleaned, 50mL/L of sulfuric acid is prepared to be used as activating solution, and the copper alloy is taken out and cleaned after being activated for 60s at room;
(3) coloring: heating the coloring liquid prepared in the step (1) to 80 ℃ and keeping the temperature constant, immersing the copper alloy treated in the step (2) into the coloring liquid and slowly stirring, soaking for 60s to realize silver gray coloring, then taking out the copper alloy, washing with clear water and drying, and protecting by using wax.
The invention has the advantages of convenient operation, high efficiency, reliability, good effect and simple formula, and is suitable for popularization and application of constant-temperature silver oxide gray coloring of copper alloy.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and any simple modification, equivalent change and modification made to the above embodiment according to the technical spirit of the present invention are within the scope of the present invention without departing from the technical spirit of the present invention.

Claims (1)

1. The method for coloring the silver gray oxide at constant temperature of the copper alloy is characterized by comprising the following steps of:
(1) preparing a coloring liquid: weighing 15-20g of lead carbonate, placing the lead carbonate in a beaker with the capacity of 1L, adding 200mL of deionized water, stirring and dissolving, weighing 35-40mL of acetic acid, slowly stirring and adding the acetic acid into the solution, standing the solution for 30min, weighing 45-60g of sodium thiosulfate, adding the sodium thiosulfate into the standing solution, stirring and dissolving, and standing for 60min to obtain a coloring solution;
(2) copper alloy pretreatment: firstly, measuring 40-60g of oil powder LCX-52 (industrial grade), adding water to dilute the oil powder LCX-52 to 1L, heating the oil powder LCX-52 to 50-60 ℃, then placing the copper alloy in deoiling liquid to carry out ultrasonic deoiling, taking out the oil powder after 30-60s, washing the oil powder with deionized water, then weighing 90-120g of chromic anhydride and 10-15mL of sulfuric acid, adding water to dilute the copper alloy to 1L, uniformly stirring the mixture to prepare polishing solution, taking out the copper alloy after chemical polishing for 5-15s, washing the copper alloy, then preparing 20-50mL/L of sulfuric acid as activating solution, taking out the copper alloy after activating the copper alloy for 30-60s at room temperature;
(3) coloring: heating the coloring liquid prepared in the step (1) to 80 ℃ and keeping the temperature constant, immersing the copper alloy treated in the step (2) into the coloring liquid and slowly stirring, soaking for 50-60s to realize silver gray coloring, then taking out the copper alloy, washing with clear water and drying, and protecting by using wax.
CN202011373231.9A 2020-11-30 2020-11-30 Method for coloring silver oxide gray at constant temperature of copper alloy Pending CN112458447A (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101054699A (en) * 2007-02-12 2007-10-17 伟业重工(安徽)有限公司 Plating technique for substituting chemical oxidation of copper and copper alloy
CN101109079A (en) * 2007-08-23 2008-01-23 黄炜棠 Hot tinting method on copper surface
CN104630760A (en) * 2015-01-23 2015-05-20 沈阳理工大学 Preparation method for preparing purple chemical conversion film on surface of yellow brass
CN106245022A (en) * 2016-07-27 2016-12-21 罗婷元 A kind of copper artware color method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101054699A (en) * 2007-02-12 2007-10-17 伟业重工(安徽)有限公司 Plating technique for substituting chemical oxidation of copper and copper alloy
CN101109079A (en) * 2007-08-23 2008-01-23 黄炜棠 Hot tinting method on copper surface
CN104630760A (en) * 2015-01-23 2015-05-20 沈阳理工大学 Preparation method for preparing purple chemical conversion film on surface of yellow brass
CN106245022A (en) * 2016-07-27 2016-12-21 罗婷元 A kind of copper artware color method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
忙子丹等: "在硫代硫酸钠-醋酸铅双组份体系中黄铜器表面着色的动力学研究", 《文物保护与考古科学》 *
蔡棣清等: "铜及铜合金化学抛光", 《材料保护》 *

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