CN108642350A - A kind of anticorrosion aluminium ally section and its surface treatment method - Google Patents

A kind of anticorrosion aluminium ally section and its surface treatment method Download PDF

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CN108642350A
CN108642350A CN201810693422.XA CN201810693422A CN108642350A CN 108642350 A CN108642350 A CN 108642350A CN 201810693422 A CN201810693422 A CN 201810693422A CN 108642350 A CN108642350 A CN 108642350A
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surface treatment
treatment method
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CN108642350B (en
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钱顺妹
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Huzhou Yang Xi Electrification Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C21/00Alloys based on aluminium
    • C22C21/10Alloys based on aluminium with zinc as the next major constituent
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C24/00Coating starting from inorganic powder
    • C23C24/02Coating starting from inorganic powder by application of pressure only
    • C23C24/04Impact or kinetic deposition of particles
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D11/00Electrolytic coating by surface reaction, i.e. forming conversion layers
    • C25D11/02Anodisation
    • C25D11/04Anodisation of aluminium or alloys based thereon
    • C25D11/06Anodisation of aluminium or alloys based thereon characterised by the electrolytes used
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25FPROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
    • C25F1/00Electrolytic cleaning, degreasing, pickling or descaling
    • C25F1/02Pickling; Descaling
    • C25F1/04Pickling; Descaling in solution

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Mechanical Engineering (AREA)
  • Electrochemistry (AREA)
  • Prevention Of Electric Corrosion (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)

Abstract

The invention discloses a kind of anticorrosion aluminium ally section and its surface treatment method, anticorrosion aluminium ally section is made of the raw material for including following weight proportion, Zn:5.1~5.6 parts, Cu:1.4~1.8 parts, Mg:1.8~2.6 parts, Mn:0.28~0.42 part, Si:0.5~1.5 part, Fe:0.7~1 part, Zr:0.08~0.12 part, surplus is Al and inevitable impurity.Surface treatment method includes oil removal treatment, acid electrolysis, alkali electrolysis, anodic oxidation and alloy coating spraying.The present invention has the characteristics that improve aluminium alloy extrusions corrosion resistance and stain resistance.

Description

A kind of anticorrosion aluminium ally section and its surface treatment method
Technical field
The present invention relates to a kind of anticorrosion aluminium ally section, especially a kind of anticorrosion aluminium ally section and its surface treatment Method.
Background technology
Due to being added to High Contents of Magnesium, element silicon in aluminium alloy, its casting character can be improved, increase material hardness and strong Degree, but also reduces its corrosion resistance.For architectural aluminum section and other industrial aluminum profiles, surface treatment is to further increase aluminium profiles Material case hardness, corrosion resistance and the indispensable technical process of aesthetic measure.The table of industrial common aluminium and its alloy Surface treatment technique is anodic oxidation, electrolytic coloring and electrophoretic painting, wherein the most universal with anodic oxidation.The sun of aluminium and its alloy Pole aoxidizes while being dissolved from surface with aluminium oxide in two processes of Surface Creation comprising metallic aluminium, and final result is in material surface One layer of micron-sized aluminum oxide film is generated, plays the role of improving hardness and corrosion proof.Aluminium alloy containing magnesium, silicon passes through Anodized after the dissolving of surface metal aluminium, exposes not oxidized elemental silicon, and the aluminum oxide film of generation is not easy covering list Matter silicon, gap caused by silicon particle easily corrode.The existing technique to being surface-treated containing magnesium, silico-aluminum, generation Anode oxide film can have a large amount of microcellular structure units, and the density of lack of homogeneity, oxidation film is not big enough, be easy suffering erosion property from The corrosion failure of son;Micropore is also easy to the pollutant in absorption environment, influences the appearance, its corrosion resistance and stain resistance of film not Enough ideals, need to be improved.Therefore, the existing technique to being surface-treated containing magnesium, silico-aluminum, the aluminium that has that treated Alloy profile corrosion resistance and the not ideal enough problem of stain resistance.
Invention content
The object of the present invention is to provide a kind of anticorrosion aluminium ally section and its surface treatment methods.The present invention has The characteristics of improving aluminium alloy extrusions corrosion resistance and stain resistance.
Technical scheme of the present invention:A kind of anticorrosion aluminium ally section, it is made of the raw material for including following weight proportion, Zn:5.1~5.6 parts, Cu:1.4~1.8 parts, Mg:1.8~2.6 parts, Mn:0.28~0.42 part, Si:0.5~1.5 part, Fe: 0.7~1 part, Zr:0.08~0.12 part, surplus is Al and inevitable impurity.
A kind of surface treatment method of above-mentioned anticorrosion aluminium ally section, includes the following steps:
A, aluminium alloy is placed in oil removing groove, degreaser is added, the oil removal treatment at 70-90 DEG C of temperature, then 60-70 DEG C Water rinses, and the cleaning of room temperature water flowing obtains a product;
B, a product are placed in electrolytic cell, acid electrolyte is added into electrolytic cell, be powered, at 40-60 DEG C, current density 6 ~12A/dm2Under carry out electrolysis processing 3-5min, obtain b product;
C, b product are again placed in electrolytic cell, alkaline electrolyte is added into electrolytic cell, be powered, at 50-80 DEG C, electric current is close Degree is 6~12A/dm2Under carry out electrolysis processing 3-5min, obtain c product;
D, c product are placed in oxidation trough, 0.2 part of 1 part of sulfuric acid, 4 parts of deionized water and oxalic acid progress anodic oxidation, temperature is added Degree is 12-25 DEG C, and current density is 1~2A/dm2, voltage 13-23V, time 30-40min then take out and are placed in boiling water Middle processing 30-50min takes out drying, obtains d product;
E, d product are placed under the protection atmosphere of nitrogen and are sprayed using alloy coating, the alloy coating includes following The raw material of weight proportion is made:50-60 parts of zinc powder, 10-20 parts of nickel powder, 5-10 parts of carborundum powder, are tuned into coating after mixed grinding, It is sprayed on the surface of d product, obtains aluminium alloy extrusions.
In surface treatment method above-mentioned, degreaser includes sodium hydroxide 60-80g/l, tricresyl phosphate pot 30-50g/l, surface Activating agent 6-8g/l.
In surface treatment method above-mentioned, in the step b, acid electrolyte includes that the raw material of following weight proportion is made: 1 part of ferrous sulfate, 1 part of copper sulphate, 0.5 part of hydrochloric acid.
In surface treatment method above-mentioned, the alkaline electrolyte includes that the raw material of following weight proportion is made:Sodium hydroxide 1 Part, 1 part of copper sulphate, 0.2 part of iron chloride.
In surface treatment method above-mentioned, the step e is to be placed in d product under the protection atmosphere of nitrogen to apply using alloy Material is sprayed, and the alloy coating includes that the raw material of following weight proportion is made:50-60 parts of zinc powder, 10-20 parts of nickel powder, carbon 5-10 parts of SiClx powder, is tuned into coating after mixed grinding, be sprayed on the surface of d product, and coating thickness 0.4-0.6mm is then placed in 30-60min is heated in 200-400 DEG C of high temperature furnace, then is air-cooled to room temperature, obtains aluminium alloy extrusions.
Compared with prior art, by optimizing the metal formulations of aluminium alloy extrusions, the intensity, hard of aluminium alloy extrusions is improved Then degree, toughness, wear-resisting property and thermal stability recycle the surface treatment in later stage, are first gone before carrying out anodic oxidation It is electrolysed except the greasy dirt in aluminium alloy extrusions, and by soda acid, removes the oxidation film naturally occurred, it is equal to generate quality convenient for the later stage Even oxidation film, and acid and alkaline condition is adapted to, when carrying out electrolytic oxidation process, increased a small amount of oxalic acid improves oxidation The hardness of film recycles the micropore in boiling water closing oxidation film, drying to reduce micropore, improve the density of oxidation film, ensures oxidation The uniformity and high compactness of film, then the sprayed coating on aluminium alloy again, forms a coating layer, and covering, protection effect are good, Consistency and intensity are improved, the exposure of aluminium alloy interior metal is avoided, the burn into of suffering erosion property ion is avoided to pollute, destroy, Intensity is high, service life is long.Therefore, the present invention has the characteristics that improve aluminium alloy extrusions corrosion resistance and stain resistance.
Specific implementation mode
With reference to embodiment, the present invention is further illustrated, but is not intended as the foundation limited the present invention.
Embodiment 1.
A kind of anticorrosion aluminium ally section, it is made of the raw material for including following weight proportion, Zn:5.1~5.6 parts, Cu: 1.4~1.8 parts, Mg:1.8~2.6 parts, Mn:0.28~0.42 part, Si:0.5~1.5 part, Fe:0.7~1 part, Zr:0.08~ 0.12 part, surplus is Al and inevitable impurity.
A kind of surface treatment method of above-mentioned anticorrosion aluminium ally section, includes the following steps:
A, aluminium alloy is placed in oil removing groove, degreaser is added, degreaser includes sodium hydroxide 60-80g/l, tricresyl phosphate pot 30-50g/l, surfactant 6-8g/l, the oil removal treatment at 70-90 DEG C of temperature, then 60-70 DEG C of water rinsing, room temperature flow Dynamic cleaning, obtains a product;
B, a product are placed in electrolytic cell, acid electrolyte is added into electrolytic cell, acid electrolyte includes following weight proportion Raw material is made:1 part of ferrous sulfate, 1 part of copper sulphate, 0.5 part of hydrochloric acid are powered, and at 40-60 DEG C, current density is 6~12A/dm2 Under carry out electrolysis processing 3-5min, obtain b product;
C, b product are again placed in electrolytic cell, alkaline electrolyte is added into electrolytic cell, the alkaline electrolyte includes following heavy The raw material of amount proportioning is made:1 part of sodium hydroxide, 1 part of copper sulphate, 0.2 part of iron chloride are powered, at 50-80 DEG C, current density 6 ~12A/dm2Under carry out electrolysis processing 3-5min, obtain c product;
D, c product are placed in oxidation trough, 0.2 part of 1 part of sulfuric acid, 4 parts of deionized water and oxalic acid progress anodic oxidation, temperature is added Degree is 12-25 DEG C, and current density is 1~2A/dm2, voltage 13-23V, time 30-40min then take out and are placed in boiling water Middle processing 30-50min takes out drying, obtains d product;The temperature of boiling water is 70-100 DEG C.
E, d product are placed under the protection atmosphere of nitrogen and are sprayed using alloy coating, the alloy coating includes following The raw material of weight proportion is made:50-60 parts of zinc powder, 10-20 parts of nickel powder, 5-10 parts of carborundum powder, are tuned into coating after mixed grinding, It is sprayed on the surface of d product, coating thickness 0.4-0.6mm is then placed in 200-400 DEG C of high temperature furnace and heats 30-60min, It is air-cooled to room temperature again, obtains aluminium alloy extrusions.
Embodiment 2.
A kind of anticorrosion aluminium ally section, it is made of the raw material for including following weight proportion, Zn:5.2 parts, Cu:1.4 Part, Mg:2.3 parts, Mn:1.30 parts, Si:0.8 part, Fe:0.8 part, Zr:0.11 part, surplus is Al and inevitable impurity.
A kind of surface treatment method of above-mentioned anticorrosion aluminium ally section, includes the following steps:
A, aluminium alloy is placed in oil removing groove, degreaser is added, degreaser includes sodium hydroxide 65g/l, tricresyl phosphate pot 35g/l, surfactant 7g/l, the oil removal treatment at 80 DEG C of temperature, then 65 DEG C of water rinsings, the cleaning of room temperature water flowing obtain a Product;
B, a product are placed in electrolytic cell, acid electrolyte is added into electrolytic cell, acid electrolyte includes following weight proportion Raw material is made:1 part of ferrous sulfate, 1 part of copper sulphate, 0.5 part of hydrochloric acid are powered, at 40-60 DEG C, current density 8A/dm2Under into Row electrolysis processing 3min, obtains b product;
C, b product are again placed in electrolytic cell, alkaline electrolyte is added into electrolytic cell, the alkaline electrolyte includes following heavy The raw material of amount proportioning is made:1 part of sodium hydroxide, 1 part of copper sulphate, 0.2 part of iron chloride are powered, at 55 DEG C, current density 6A/ dm2Under carry out electrolysis processing 3min, obtain c product;
D, c product are placed in oxidation trough, 0.2 part of 1 part of sulfuric acid, 4 parts of deionized water and oxalic acid progress anodic oxidation, temperature is added Degree is 12-25 DEG C, and current density is 1~2A/dm2, voltage 13-23V, time 30-40min then take out and are placed in boiling water Middle processing 30-50min takes out drying, obtains d product;
E, d product are placed under the protection atmosphere of nitrogen and are sprayed using alloy coating, the alloy coating includes following The raw material of weight proportion is made:50 parts of zinc powder, 10 parts of nickel powder, 5 parts of carborundum powder, are tuned into coating, are sprayed on d product after mixed grinding Surface, coating thickness 0.4mm is then placed in 200 DEG C of high temperature furnace and heats 30min, then be air-cooled to room temperature, obtains aluminium alloy Proximate matter.

Claims (6)

1. a kind of anticorrosion aluminium ally section, it is characterised in that:It is made of the raw material for including following weight proportion, Zn:5.1~ 5.6 parts, Cu:1.4~1.8 parts, Mg:1.8~2.6 parts, Mn:0.28~0.42 part, Si:0.5~1.5 part, Fe:0.7~1 part, Zr:0.08~0.12 part, surplus is Al and inevitable impurity.
2. a kind of surface treatment method of anticorrosion aluminium ally section according to claim 1, it is characterised in that:Including with Lower step:
A, aluminium alloy is placed in oil removing groove, degreaser is added, the oil removal treatment at 70-90 DEG C of temperature, then 60-70 DEG C of water drift It washes, the cleaning of room temperature water flowing obtains a product;
B, a product are placed in electrolytic cell, acid electrolyte is added into electrolytic cell, be powered, at 40-60 DEG C, current density is 6~ 12A/dm2Under carry out electrolysis processing 3-5min, obtain b product;
C, b product are again placed in electrolytic cell, alkaline electrolyte is added into electrolytic cell, be powered, at 50-80 DEG C, current density 6 ~12A/dm2Under carry out electrolysis processing 3-5min, obtain c product;
D, c product are placed in oxidation trough, 0.2 part of 1 part of sulfuric acid, 4 parts of deionized water and oxalic acid progress anodic oxidation is added, temperature is 12-25 DEG C, current density is 1~2A/dm2, voltage 13-23V, time 30-40min then take out and are placed in boiling water 30-50min is managed, drying is taken out, obtains d product;
E, d product are placed under the protection atmosphere of nitrogen and are sprayed using alloy coating, the alloy coating includes following weight The raw material of proportioning is made:50-60 parts of zinc powder, 10-20 parts of nickel powder, 5-10 parts of carborundum powder, are tuned into coating after mixed grinding, spraying On the surface of d product, aluminium alloy extrusions is obtained.
3. surface treatment method according to claim 2, it is characterised in that:In the step a, degreaser includes hydroxide Sodium 60-80g/l, tricresyl phosphate pot 30-50g/l, surfactant 6-8g/l.
4. a kind of surface treatment method of anticorrosion aluminium ally section according to claim 2, it is characterised in that:The step In rapid b, acid electrolyte includes that the raw material of following weight proportion is made:1 part of ferrous sulfate, 1 part of copper sulphate, 0.5 part of hydrochloric acid.
5. a kind of surface treatment method of anticorrosion aluminium ally section according to claim 2, it is characterised in that:The alkali Electrolyte includes that the raw material of following weight proportion is made:1 part of sodium hydroxide, 1 part of copper sulphate, 0.2 part of iron chloride.
6. a kind of surface treatment method of anticorrosion aluminium ally section according to claim 2, it is characterised in that:The step Rapid e is to be placed in d product under the protection atmosphere of nitrogen to spray using alloy coating, and the alloy coating includes following weight The raw material of proportioning is made:50-60 parts of zinc powder, 10-20 parts of nickel powder, 5-10 parts of carborundum powder, are tuned into coating after mixed grinding, spraying On the surface of d product, coating thickness 0.4-0.6mm is then placed in 200-400 DEG C of high temperature furnace and heats 30-60min, then empty It is cooled to room temperature, obtains aluminium alloy extrusions.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110527880A (en) * 2019-08-27 2019-12-03 福建省漳州安泰铝材有限公司 A kind of anodic oxidation aluminum profile and its preparation process

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102876942A (en) * 2012-09-04 2013-01-16 昆山市源丰铝业有限公司 Aluminum alloy plate for vehicle
CN106676340A (en) * 2016-11-28 2017-05-17 安徽省煜灿新型材料科技有限公司 High-strength wear-resistant electrophoretic aluminum alloy profile
CN108048891A (en) * 2017-11-15 2018-05-18 重庆嘉萌鸿业科技有限公司 A kind of aluminium alloy castings surface treatment method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102876942A (en) * 2012-09-04 2013-01-16 昆山市源丰铝业有限公司 Aluminum alloy plate for vehicle
CN106676340A (en) * 2016-11-28 2017-05-17 安徽省煜灿新型材料科技有限公司 High-strength wear-resistant electrophoretic aluminum alloy profile
CN108048891A (en) * 2017-11-15 2018-05-18 重庆嘉萌鸿业科技有限公司 A kind of aluminium alloy castings surface treatment method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110527880A (en) * 2019-08-27 2019-12-03 福建省漳州安泰铝材有限公司 A kind of anodic oxidation aluminum profile and its preparation process
CN110527880B (en) * 2019-08-27 2020-10-16 福建省漳州安泰铝材有限公司 Anodic aluminum oxide profile and preparation process thereof

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