CN109628918A - A kind of color chemical oxidation technique of magnesium alloy - Google Patents
A kind of color chemical oxidation technique of magnesium alloy Download PDFInfo
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- CN109628918A CN109628918A CN201910135708.0A CN201910135708A CN109628918A CN 109628918 A CN109628918 A CN 109628918A CN 201910135708 A CN201910135708 A CN 201910135708A CN 109628918 A CN109628918 A CN 109628918A
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- Prior art keywords
- magnesium alloy
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- oxidation
- water
- chemical oxidation
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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
- C23C22/24—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 containing hexavalent chromium compounds
-
- 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
Abstract
Present invention discloses a kind of color chemical oxidation techniques of magnesium alloy, comprising the following steps: Mg alloy surface cleaning treatment, magnesium alloy obtain cleaning magnesium alloy after surface degreasing, surface caustic corrosion, surface acid-washing, the cleaning of surface water；Configuration oxidation solution, aoxidizes the CrO that solution includes: 1.5 ~ 2.5g according to every mass per liter accounting3, 0.3 ~ 0.6g H2SO4, 0.15~0.2gNaCl, surplus be water and for adjusts oxidation solution pH value NaOH, aoxidize solution pH range be 4~5.5；Color chemical oxidation, it is to take out, and cleaned up in clear water by 20 ~ 30s in 18~28 DEG C of oxidation solution, obtain Coloured Anodizing magnesium alloy that cleaning magnesium alloy, which is immersed in temperature,；Last Mg alloy surface is dried.Present invention oxidation solution chrome content is lower, and it is more environmentally friendly to compare traditional oxidation solution, and obtains oxidation film outward appearance in colored, electric conductivity is good.Process flow is succinct, is easy to deploy, widely applicable.
Description
Technical field
The present invention relates to a kind of color chemical oxidation technique more particularly to a kind of color chemical oxidation technique of magnesium alloy,
Belong to the technical field of metal material surface processing.
Background technique
Distinctive performance advantages possessed by magnesium alloy, have at home and abroad received significant attention, and application range is not yet
It is disconnected to be expanded in every field, the fields such as automobile and electronic product, magnesium are increasingly applied in particular with magnesium alloy
The decorative surface of alloy is just becoming a factor be must be taken into consideration, the magnesium alloy die casting as product, it is necessary to which satisfaction disappears
The person of expense is to the multifarious requirement of its surface color and polish.
Magnesium alloy can also be protected with metal coating, and plating, chemical plating or heat spraying method can be used in metal coating
It obtains, since the fusing point of magnesium alloy is very low, plating and chemical plating is commonly used, without the method using thermal spraying.Since magnesium closes
Gold it is very active, MgO can be quickly formed in Mg alloy surface, thus Mg alloy surface directly be electroplated or chemical plating very be stranded
Difficulty, substrate pretreated difficulty are also larger.It is generally zinc-plated using chemical conversion, then copper facing, after magnesium alloy plates one layer of copper, then
Required metal is plated by common electro-plating method, the electroplated layer more generally used at present selects Cu, Ni or Cr layers mostly.
Chemical deposit is usually N-iP layers.Improve the method for Mg alloy surface color mainly by plating coloured gold on its surface
Belong to, such as copper facing, surface is in aubergine；Nickel plating, surface are in pearl white, chromium plating；Surface is in blue and white.
For AZ63 magnesium alloy, processing is substantially in containing chromic salts or fluoride salt to obtain oxidation film layer, these formulas
In containing the pollution factors such as chromium or fluorine ion, and ion concentration is higher, brings no small pressure to environmental protection.
Summary of the invention
Present invention aim to address above-mentioned the deficiencies in the prior art, for there are ion concentrations in traditional magnesium alloy formula
It is higher that pollution is led to the problem of to environment, propose a kind of color chemical oxidation technique of magnesium alloy.
In order to achieve the above object, the technical scheme adopted by the invention is as follows:
A kind of color chemical oxidation technique of magnesium alloy, the magnesium alloy are AZ63 magnesium alloy,
The following steps are included:
S1 Mg alloy surface cleaning treatment,
Magnesium alloy obtains cleaning magnesium alloy after surface degreasing, surface caustic corrosion, surface acid-washing, the cleaning of surface water；
S2 configuration oxidation solution,
Aoxidize the CrO that solution includes: 1.5 ~ 2.5g according to every mass per liter accounting3, 0.3 ~ 0.6g H2SO4, 0.15~
0.2gNaCl, surplus are water and the NaOH for adjusting oxidation solution pH value, and the pH range of the oxidation solution is 4~5.5；
S3 color chemical oxidation,
It is to take out by 20 ~ 30s, and clean in clear water in 18~28 DEG C of oxidation solution that cleaning magnesium alloy, which is immersed in temperature,
Completely, Coloured Anodizing magnesium alloy is obtained；
S4 Mg alloy surface is dried,
Dry tack free processing is carried out to Coloured Anodizing magnesium alloy by way of drying up and/or drying.
Preferably, the oxidation solution includes: the CrO of 2.5g according to every mass per liter accounting3, 0.4g H2SO4、
0.2gNaCl, surplus are water and the NaOH for adjusting oxidation solution pH value, and the pH value of the oxidation solution is 5.
Preferably, the oxidation solution includes: the CrO of 2g according to every mass per liter accounting3, 0.5g H2SO4、
0.15gNaCl, surplus are water and the NaOH for adjusting oxidation solution pH value, and the pH value of the oxidation solution is 5.5.
Preferably, the oxidation solution includes: the CrO of 1.5g according to every mass per liter accounting3, 0.3g H2SO4、
0.2gNaCl, surplus are water and the NaOH for adjusting oxidation solution pH value, and the pH value of the oxidation solution is 4.
Preferably, the step S1 includes:
S11 electrochemical deoiling,
It is to take out after 10~30min, and in clear water in 70~90 DEG C of electrochemical deoiling solution that magnesium alloy, which is immersed in temperature,
It cleans up；
S12 caustic corrosion,
It is to be taken after 5~15min in 70~80 DEG C of caustic corrosion solution by magnesium alloy is immersed in temperature after oil removal treatment
Out, and in clear water it cleans up；
The processing of S13 acid,
Will by caustic corrosion, treated that magnesium alloy is immersed in acid solution under room temperature, taken out after 10~15min,
And it is cleaned up in clear water.
Preferably, the electrochemical deoiling solution includes 10 ~ 25gNaOH, 40 ~ 60gNa according to every mass per liter accounting3PO4▪
12H2O、20~30gNa2O▪nSiO2, surplus be water.
Preferably, the caustic corrosion solution is the NaOH solution of 260 ~ 310g/L.
Preferably, the acid solution is the CrO of 150 ~ 250g/L3Solution.
Preferably, the step S4 includes:
S41 drying,
It is water stain that the piece surface after chemical oxidation is dried up with clean compressed air；
S42 drying,
Drying temperature is 50~70 DEG C, and the time is 20min~30min.
The beneficial effects are mainly reflected as follows:
1. it is lower to aoxidize solution chrome content, it is more environmentally friendly to compare traditional oxidation solution, and obtains oxidation film outward appearance and is in colour, leads
It is electrically good.
2. process flow is succinct, it is easy to deploy, it is widely applicable.
Detailed description of the invention
Fig. 1 is a kind of flow diagram of the color chemical oxidation technique of magnesium alloy of the present invention.
Specific embodiment
The present invention provides a kind of color chemical oxidation technique of magnesium alloy.Below in conjunction with attached drawing to technical solution of the present invention into
Row detailed description, so that it is more readily understood and grasps.
A kind of color chemical oxidation technique of magnesium alloy, magnesium alloy are AZ63 magnesium alloy, as shown in Figure 1 include following step
It is rapid:
S1 Mg alloy surface cleaning treatment,
Magnesium alloy obtains cleaning magnesium alloy after surface degreasing, surface caustic corrosion, surface acid-washing, the cleaning of surface water.
S2 configuration oxidation solution,
Aoxidize the CrO that solution includes: 1.5 ~ 2.5g according to every mass per liter accounting3, 0.3 ~ 0.6g H2SO4, 0.15~
0.2gNaCl, surplus are water and the NaOH for adjusting oxidation solution pH value, and the pH range of the oxidation solution is 4~5.5.
S3 color chemical oxidation,
It is to take out by 20 ~ 30s, and clean in clear water in 18~28 DEG C of oxidation solution that cleaning magnesium alloy, which is immersed in temperature,
Completely, Coloured Anodizing magnesium alloy is obtained.
S4 Mg alloy surface is dried,
Dry tack free processing is carried out to Coloured Anodizing magnesium alloy by way of drying up and/or drying.
Embodiment one
Aoxidize the CrO that solution includes: 2.5g according to every mass per liter accounting3, 0.4g H2SO4, 0.2gNaCl, surplus be water and use
In the NaOH for adjusting oxidation solution pH value, the pH value for aoxidizing solution is 5.
Embodiment two
Aoxidize the CrO that solution includes: 2g according to every mass per liter accounting3, 0.5g H2SO4, 0.15gNaCl, surplus be water and to be used for
The NaOH of oxidation solution pH value is adjusted, the pH value of the oxidation solution is 5.5.
Embodiment three
Aoxidize the CrO that solution includes: 1.5g according to every mass per liter accounting3, 0.3g H2SO4, 0.2gNaCl, surplus be water and use
In the NaOH for adjusting oxidation solution pH value, the pH value for aoxidizing solution is 4.
Through detecting, using the oxidation solution of embodiment one to embodiment three, AZ63 Mg alloy surface generates colored oxide film,
And has electrical conductance, the thickness that oxidation film compares traditional high chrome contents oxidation film is declined, and electrical conductance is similar.
Refinement description is carried out to Mg alloy surface cleaning treatment step:
Electrochemical deoiling,
It is to take out after 10~30min, and in clear water in 70~90 DEG C of electrochemical deoiling solution that magnesium alloy, which is immersed in temperature,
It cleans up.
Caustic corrosion,
It is to be taken after 5~15min in 70~80 DEG C of caustic corrosion solution by magnesium alloy is immersed in temperature after oil removal treatment
Out, and in clear water it cleans up.
Acid processing,
Will by caustic corrosion, treated that magnesium alloy is immersed in acid solution under room temperature, taken out after 10~15min,
And it is cleaned up in clear water.
Wherein, electrochemical deoiling solution includes 10 ~ 25gNaOH, 40 ~ 60gNa according to every mass per liter accounting3PO4▪12H2O、20~
30gNa2O▪nSiO2, surplus be water.It is able to achieve to Mg alloy surface oil removing.Caustic corrosion solution is that the NaOH of 260 ~ 310g/L is molten
Liquid.Acid solution is the CrO of 150 ~ 250g/L3Solution.Using the composition in formula as acid, alkali and the main ingredient of oil removing, such as
This entire technological design Formulation Ingredients quantity is reduced, and is easy to integrated artistic realization.
Step is dried to Mg alloy surface to refine:
It is water stain to dry up the piece surface after chemical oxidation with clean compressed air for drying.
Drying, drying temperature are 50~70 DEG C, and the time is 20min~30min.
By above description it can be found that a kind of color chemical oxidation technique of magnesium alloy of the present invention, oxidation solution contain chromium
Measure lower, it is more environmentally friendly to compare traditional oxidation solution, and obtains oxidation film outward appearance in colored, electric conductivity is good.Process flow
Succinctly, it is easy to deploy, it is widely applicable.
Technical solution of the present invention is fully described above, it should be noted that specific embodiment party of the invention
Formula is simultaneously not limited by the description set out above, the Spirit Essence of those skilled in the art according to the present invention structure, method or
All technical solutions that function etc. is formed using equivalents or equivalent transformation, all fall within protection scope of the present invention
Within.
Claims (9)
1. a kind of color chemical oxidation technique of magnesium alloy, the magnesium alloy is AZ63 magnesium alloy,
Characterized by the following steps:
S1 Mg alloy surface cleaning treatment,
Magnesium alloy obtains cleaning magnesium alloy after surface degreasing, surface caustic corrosion, surface acid-washing, the cleaning of surface water；
S2 configuration oxidation solution,
Aoxidize the CrO that solution includes: 1.5 ~ 2.5g according to every mass per liter accounting3, 0.3 ~ 0.6g H2SO4, 0.15~
0.2gNaCl, surplus are water and the NaOH for adjusting oxidation solution pH value, and the pH range of the oxidation solution is 4~5.5；
S3 color chemical oxidation,
It is to take out by 20 ~ 30s, and clean in clear water in 18~28 DEG C of oxidation solution that cleaning magnesium alloy, which is immersed in temperature,
Completely, Coloured Anodizing magnesium alloy is obtained；
S4 Mg alloy surface is dried,
Dry tack free processing is carried out to Coloured Anodizing magnesium alloy by way of drying up and/or drying.
2. the color chemical oxidation technique of a kind of magnesium alloy according to claim 1, it is characterised in that:
The oxidation solution includes: the CrO of 2.5g according to every mass per liter accounting3, 0.4g H2SO4, 0.2gNaCl, surplus be water
PH value with the NaOH for adjusting oxidation solution pH value, the oxidation solution is 5.
3. the color chemical oxidation technique of a kind of magnesium alloy according to claim 1, it is characterised in that:
The oxidation solution includes: the CrO of 2g according to every mass per liter accounting3, 0.5g H2SO4, 0.15gNaCl, surplus be water and
For adjusting the NaOH of oxidation solution pH value, the pH value of the oxidation solution is 5.5.
4. the color chemical oxidation technique of a kind of magnesium alloy according to claim 1, it is characterised in that:
The oxidation solution includes: the CrO of 1.5g according to every mass per liter accounting3, 0.3g H2SO4, 0.2gNaCl, surplus be water
PH value with the NaOH for adjusting oxidation solution pH value, the oxidation solution is 4.
5. the color chemical oxidation technique of a kind of magnesium alloy according to claim 1, it is characterised in that the step S1 includes:
S11 electrochemical deoiling,
It is to take out after 10~30min, and in clear water in 70~90 DEG C of electrochemical deoiling solution that magnesium alloy, which is immersed in temperature,
It cleans up；
S12 caustic corrosion,
It is to be taken after 5~15min in 70~80 DEG C of caustic corrosion solution by magnesium alloy is immersed in temperature after oil removal treatment
Out, and in clear water it cleans up；
The processing of S13 acid,
Will by caustic corrosion, treated that magnesium alloy is immersed in acid solution under room temperature, taken out after 10~15min,
And it is cleaned up in clear water.
6. the color chemical oxidation technique of a kind of magnesium alloy according to claim 5, it is characterised in that:
The electrochemical deoiling solution includes 10 ~ 25gNaOH, 40 ~ 60gNa according to every mass per liter accounting3PO4▪12H2O、20~
30gNa2O▪nSiO2, surplus be water.
7. the color chemical oxidation technique of a kind of magnesium alloy according to claim 5, it is characterised in that:
The caustic corrosion solution is the NaOH solution of 260 ~ 310g/L.
8. the color chemical oxidation technique of a kind of magnesium alloy according to claim 5, it is characterised in that:
The acid solution is the CrO of 150 ~ 250g/L3Solution.
9. the color chemical oxidation technique of a kind of magnesium alloy according to claim 1, it is characterised in that the step S4 includes:
S41 drying,
It is water stain that the piece surface after chemical oxidation is dried up with clean compressed air；
S42 drying,
Drying temperature is 50~70 DEG C, and the time is 20min~30min.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115491666A (en) * | 2022-09-07 | 2022-12-20 | 深圳市飞航精工科技有限公司 | Conductive oxidation process for magnesium alloy high-salt-spray test |
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| JPS6439381A (en) * | 1987-08-04 | 1989-02-09 | Mitsubishi Electric Corp | Treating solution for chemical film on magnesium alloy |
| CN1673412A (en) * | 2005-04-12 | 2005-09-28 | 沈阳工业大学 | Magnesium and magnesium alloy chemical oxidation process |
| CN109161878A (en) * | 2018-11-08 | 2019-01-08 | 北京星航机电装备有限公司 | A kind of porous type ZM6 magnesium alloy parts gold is film chemical oxidation technology |
| CN109252198A (en) * | 2018-12-06 | 2019-01-22 | 嘉兴市劼力机械科技有限公司 | A kind for the treatment of process of the iron-based handware of anticorrosion |
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2019
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6439381A (en) * | 1987-08-04 | 1989-02-09 | Mitsubishi Electric Corp | Treating solution for chemical film on magnesium alloy |
| CN1673412A (en) * | 2005-04-12 | 2005-09-28 | 沈阳工业大学 | Magnesium and magnesium alloy chemical oxidation process |
| CN109161878A (en) * | 2018-11-08 | 2019-01-08 | 北京星航机电装备有限公司 | A kind of porous type ZM6 magnesium alloy parts gold is film chemical oxidation technology |
| CN109252198A (en) * | 2018-12-06 | 2019-01-22 | 嘉兴市劼力机械科技有限公司 | A kind for the treatment of process of the iron-based handware of anticorrosion |
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| 张德忠等: "镁合金金黄色化学氧化工艺的研究", 《材料保护》 * |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115491666A (en) * | 2022-09-07 | 2022-12-20 | 深圳市飞航精工科技有限公司 | Conductive oxidation process for magnesium alloy high-salt-spray test |
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Application publication date: 20190416 |