A kind of aluminium alloy alternating current electrolysis deposition silver-bearing copper color method
[technical field]
The present invention relates to a kind of aluminium alloy alternating current electrolysis deposition silver-bearing copper color method.
[background technology]
Aluminium alloy density is low, and specific strength is higher, and near or above high-quality steel, plasticity is good, can be processed into various section bar, has excellent electric conductivity, heat conductivity and a corrosion resistance, industrial widely uses, and makes consumption be only second to steel.Along with the raising of social development and people's living standard, people recognize the harm of pathogen gradually, thereby promote the aluminium alloy exploitation with sterilization antibacterial functions.As medical aluminum alloy materials, not only there is the decay resistance of excellence, and to have sterilization antibacterial functions.
Aluminium alloy can form one layer of very thin oxide-film less than 0.1 micron, poor corrosion resistance under the natural conditions of air on its surface.Therefore, building and daily life aluminium alloy generally go through anodized, enable aluminum alloy to surface oxidation film thickness and reach 10 microns~30 microns, so not only add the decay resistance of aluminium alloy but also add intensity.
Argent and compound thereof have excellent antibiotic and sterilizing performance, it was reported that silver can kill harmful antibacterial, fungus and mycete.One of which mechanism is silver ion Releasing Mechanism, it is believed that the silver ion that the concentration of slow releasing is only small is combined with the sulfydryl of the zymoprotein of harmful bacteria, reduces the activity of protozoa organized enzyme, makes harmful bacteria inactivation kill.And the active oxygen Antibacterial Mechanism of silver ion is thought: the reduction potential of high oxidation state silver is high, under the effect of light, antibacterial and water or air effect, the active oxygen of generation and hydroxyl radical free radical, there is very strong redox and kill harmful bacteria.
Usually, being that aluminium alloy carries out in electrolyte the oxide-film of anodic oxidation formation is porous at sulphuric acid, aperture size depends on oxidizing condition, usual tens nanometers.
Application publication number is the electrochemical preparation method that the Chinese patent of CN102703950A discloses a kind of medical science external aluminium alloy multifunction coating, it is aluminum alloy base material to be carried out anodized and DC electrolysis is painted, enable aluminum alloy to surface and form porous oxide film and containing metals such as certain silver, copper, zinc, and containing self-cleaning nano titanium oxide in oxide-film top layer;It is to add a small amount of silver nitrate, sodium potassium tartrate tetrahydrate etc. in sulfuric acid electrolyte to carry out DC electrolysis deposition silver in aluminium alloy porous oxide film, then with nano titanium oxide aqueous solution sealing of hole.The pellumina formed after anodic oxidation due to aluminium alloy is made up of the barrier layer of internal layer and the porous layer of outer layer, resistivity is high, decomposition voltage is high, DC electrolysis causes waste electric energy, more seriously uses DC electrolysis can cause coloring liquid unstable (having a large amount of Precipitation in electrolytic process near negative electrode).
Authorization Notice No. is a kind of method that the Chinese patent of CN1220797C discloses golden coloring surface producing aluminum or aluminum alloy by argentiferous formula, and US Patent No. 4128460 all refers to electrolytic deposition silver in methanesulfonic acid solution, enables aluminum alloy to golden color.But the methanesulfonic acid used due to coloring liquid or alkyl sulfonic acid, painted cost is high, and painted treatment cost of waste liquor higher (not environmentally).
The Chinese patent that publication number is CN1310248A discloses a kind of automatic sterilizing zinc supplement aluminium ware and manufacturing process thereof, it discloses add in sulfuric acid electrolyte a small amount of copper sulfate, zinc sulfate and silver nitrate etc. aluminium alloy is aoxidized simultaneously and painted (step process, adopt exchange or direct current).The Chinese patent that Authorization Notice No. is CN101629316B discloses the antibacterial anticorrosive of a kind of aluminum or aluminum alloy and fastness process of surface treatment, and it adds chromic anhydride (CrO in sulfuric acid electrolyte3) and a small amount of water soluble silver salt etc. aluminium alloy is carried out ac oxide and painted (step process) simultaneously, the siliver chromate of formation and silver dichromate have antibacterial action, and last hot water is closed.Practice have shown that, although these techniques are very simple, but technical process wayward (such as film thickness and coloring consistence etc.), coloring effect is undesirable, and painted electrolyte stability is inadequate.
Japanese Patent Publication 5-14033), Unexamined Patent 10-88390 and 2002-47596) disclose aluminium alloy and first pass through anodic oxidation, then in sulphuric acid liquid, add water-soluble silver compound, by exchange or AC-DC overlaying power filling silver particles in oxide-film, obtained aluminium alloy has antibacterial ability.Practice have shown that, can with the complex of complexing of metal ion owing to not adding in coloring liquid, instability (having a certain amount of infusible precipitate to generate) in this coloring liquid electrolytic process.
In a word, current common electrolytic coloring deposition silver with the complex of silver ion complexation, can cause coloring liquid to have precipitation owing to not adding in coloring liquid, and coloring liquid is unstable and affects chromatic effect.If adding tartaric acid or citric acid (they belong to organic hydroxy-acid's class chelating agent) in common deposition silver coloring liquid, it is remarkably improved coloring liquid stability (not having precipitate), and when adopting exchange deposition, deposition process coloring liquid is without producing precipitation, coloring liquid is very stable, and coloring effect is good.But, according to DC electrolysis deposition silver, although there being chelating agent in coloring liquid, but deposition process still can produce precipitation, and coloring liquid is unstable, and coloring effect is bad.
[summary of the invention]
The technical problem to be solved in the present invention, be in that to overcome current coloring liquid poor stability and provide a kind of aluminium alloy alternating current electrolysis deposition silver-bearing copper color method, its technique is simple, easy to operate, not only uniform coloring, stable, improves the decay resistance of aluminium alloy, and the antibiotic and sterilizing rate of aluminium alloy reaches 99.0% again, and antibiotic and sterilizing acting duration is long, coloring treatment cost is low.Coloring liquid life-time service does not have insoluble deposition to precipitate out, highly stable.
The present invention is realized in above-mentioned technical problem:
A kind of aluminium alloy alternating current electrolysis deposition silver-bearing copper color method, described method step is as follows:
Step one, aluminium alloy anode oxide: using pretreated Al-alloy parts as anode, graphite as negative electrode, in following electrolyte, carry out anodic oxidation preparation there is the aluminium alloy of porous oxide film: H2SO4150~200g/L, Al2(SO4)3·18H2O5~20g/L, oxidation process conditions is as follows: temperature 19~21 DEG C, time 20~40min, DC voltage 14V;Aoxidize, taken out Al-alloy parts, in clear water, soaked the electrolyte removing surface after washing, must have the aluminium alloy of porous oxide film;
Step 2, aluminium alloy ac electrolytic coloring: form two electrodes with the Al-alloy parts and graphite with porous oxide film, carry out ac electrolytic coloring: H in following coloring liquid2SO415~20g/L, AgNO34~7g/L, CuSO4·5H2O1.5~2.5g/L, MgSO4·7H2O18~25g/L, chelating agent A2~7g/L or chelating agent B5~10g/L;Ac electrolytic coloring process conditions are as follows: temperature 5~35 DEG C, time 3~7min, voltage 4~7V;After painted, take out Al-alloy parts, in clear water, soak to remove the electrolyte on surface after washing;
Step 3, the Al-alloy parts of step 2 gained is carried out boiling water sealing treatment, obtain the aluminium alloy coloring stabilized, there is sterilizing function;
Described chelating agent A is a-amino acid, and chelating agent B is organic hydroxy-acid, and wherein the hydroxyl of organic hydroxy-acid is in α or the β position of carbochain.
Further, described a-amino acid adopts the one in glycine, alanine.
Further, described organic hydroxy-acid adopts the one in malic acid, lactic acid, gluconic acid.
Present invention have the advantage that
The coloring liquid of the inventive method is made up of sulphuric acid, silver nitrate, copper sulfate, chelating agent etc., in the present invention, chelating agent A adopts a-amino acid, a-amino acid complex be analogy organic hydroxy-acid's class chelating agent more can effectively with the complex of silver ion complexation, the four-coordination coordination compound at five rings can be formed with silver ion, therefore the coloring liquid adding a-amino acid is highly stable, in preparation and (electrolysis) process of use, coloring liquid does not all have precipitate to produce, coloring liquid is highly stable, and coloring effect is excellent.High resolution scanning Electronic Speculum (accompanying drawing 1) shows that in duct, miniature spherical granule is silver-bearing copper granule, and more uniform deposition is in duct, therefore uniform coloring, stable.X-ray energy dispersion spectrum (accompanying drawing 2) test is further characterized by duct have silver and copper.The inventive method technique is simple, easy to operate, not only uniform coloring, stable, improves the decay resistance of aluminium alloy, and the antibiotic and sterilizing rate of aluminium alloy reaches 99.0% again, and the feature such as it is long to have antibiotic and sterilizing acting duration, and coloring treatment cost is low.Coloring liquid life-time service does not have insoluble deposition to precipitate out, highly stable.Aluminium alloy prepared by the present invention can as antibiotic and sterilizing material, for instance Medical wheelchair, go-cart, stretcher, bullet train and handrail and armrest in bus, door handle, balustrade, refrigerator etc., and building and ornament materials etc..
[accompanying drawing explanation]
The present invention is further illustrated in conjunction with the embodiments with reference to the accompanying drawings.
Fig. 1 is the aluminium alloy cross section high resolution scanning Electronic Speculum figure of deposition Ag-Cu in porous oxide film prepared by the present invention (embodiment 2).
Fig. 2 is the X-ray energy dispersion spectrum with the aluminium alloy of deposition Ag-Cu in porous oxide film prepared by the present invention (embodiment 2).
[detailed description of the invention]
Refer to shown in Fig. 1~2, embodiments of the invention are described in detail.
The present invention relates to a kind of aluminium alloy alternating current electrolysis deposition silver-bearing copper color method, described method step is as follows:
Step one, aluminium alloy anode oxide: using pretreated Al-alloy parts as anode, graphite as negative electrode, in following electrolyte, carry out anodic oxidation preparation there is the aluminium alloy of porous oxide film: H2SO4150~200g/L, Al2(SO4)3·18H2O5~20g/L, oxidation process conditions is as follows: temperature 19~21 DEG C, time 20~40min, DC voltage 14V;Aoxidize, taken out Al-alloy parts, in clear water, soaked the electrolyte removing surface after washing, must have the aluminium alloy of porous oxide film;
Step 2, aluminium alloy ac electrolytic coloring: form two electrodes with the Al-alloy parts and graphite with porous oxide film, carry out ac electrolytic coloring: H in following coloring liquid2SO415~20g/L, AgNO34~7g/L, CuSO4·5H2O1.5~2.5g/L, MgSO4·7H2O18~25g/L, chelating agent A2~7g/L or chelating agent B5~10g/L;Ac electrolytic coloring process conditions are as follows: temperature 5~35 DEG C, time 3~7min, voltage 4~7V;After painted, take out Al-alloy parts, in clear water, soak to remove the electrolyte on surface after washing;
Step 3, the Al-alloy parts of step 2 gained is carried out boiling water sealing treatment, obtain the aluminium alloy coloring stabilized, there is sterilizing function;
Described chelating agent A is a-amino acid, and chelating agent B is organic hydroxy-acid, and wherein the hydroxyl of organic hydroxy-acid is in α or the β position of carbochain.
Further, described a-amino acid adopts the one in glycine, alanine.
Further, described organic hydroxy-acid adopts the one in malic acid, lactic acid, gluconic acid.
The pretreatment of the Al-alloy parts in step one is mainly alkali electroless oil removing, finite concentration sodium hydroxide solution oxide film dissolving, dust technology ash disposal, washing etc..
Coloring process deposition in step 2 is silver and copper simple substance or their oxide.
Below in conjunction with specific embodiment, the present invention is further described.
Embodiment 1:
Through pretreated aluminum alloy sheets such as defat, oxide film dissolving, ash disposal, washings containing 5g/LAl2(SO4)3·18H2O and 170g/LH2SO4In the solution of concentration, at 19~21 DEG C and 14V DC voltage electrolysis 30min, washing, immersion obtain the aluminum alloy sheet with the porous oxide film that thickness is about 15~20 microns after removing surface electrolyte.
Use H2SO417g/L,AgNO35g/L, CuSO4·5H2O1.5g/L, MgSO4·7H2O20g/L, glycine 3.2g/L prepare painted electrolyte, at temperature 25 DEG C, aluminum alloy sheet are carried out ac electrolytic coloring, after surface electrolyte is removed in then washing, immersion, and last hot water sealing treatment.Table 1 below gives the color of alternating current electrolysis aluminium alloy attachment under different time and alternating voltage.
CuSO worked as by table 14·5H2Alternating current electrolysis voltage and the time impact on alloy colouring during O1.5g/L
Embodiment 2:
After the pretreatment such as defat, oxide film dissolving, ash disposal, washing, aluminum alloy sheet is containing 5g/LAl2(SO4)3·18H2O and 170gLH2SO4In the solution of concentration, electrolysis 30min under 19~21 DEG C and 14V DC voltage, washing, immersion obtain, after removing surface electrolyte, the aluminum alloy sheet that thickness is about the porous oxide film of 15~20 microns.
Use H2SO417g/L,AgNO35g/L, CuSO4·5H2O2.0g/L, MgSO4·7H2O20g/L, glycine 3.2g/L prepare painted electrolyte.At temperature 25 DEG C, aluminum alloy sheet is carried out ac electrolytic coloring, after surface electrolyte is removed in then washing, immersion, last hot water sealing treatment.Table 2 below gives the color of alternating current electrolysis aluminium alloy attachment under different time and voltage.
CuSO worked as by table 24·5H2Alternating current electrolysis voltage and the time impact on alloy colouring during O2.0g/L
Embodiment 3:
The aluminum alloy sheet of the pre-treatment such as defat, oxide film dissolving is containing 5g/LAl2(SO4)3·18H2O and 170gLH2SO4In the solution of concentration, using DC electrolysis 30min at 19~21 DEG C and 14V, washing, immersion obtain, after removing surface electrolyte, the porous oxide film that thickness is about 15~20 microns.
Use H2SO417g/L,AgNO35g/L, CuSO4·5H2O2.5g/L, MgSO4·7H2O20g/L, glycine 3.2g/L prepare painted electrolyte.At temperature 25 DEG C, aluminum alloy sheet is carried out ac electrolytic coloring, after surface electrolyte is removed in then washing, immersion, last hot water sealing treatment.Table 3 below gives the color of alternating current electrolysis aluminium alloy attachment under different time and voltage.
CuSO worked as by table 34·5H2Alternating current electrolysis voltage and the time impact on alloy colouring during O2.5g/L
Embodiment 4:
After the pretreatment such as defat, oxide film dissolving, ash disposal, washing, aluminum alloy sheet is containing 5g/LAl2(SO4)3·18H2O and 170gLH2SO4In the solution of concentration, electrolysis 30min under 19~21 DEG C and 14V DC voltage, washing, immersion obtain, after removing surface electrolyte, the aluminum alloy sheet that thickness is about the porous oxide film of 15~20 microns.
Use H2SO417g/L,AgNO35g/L, CuSO4·5H2O2.0g/L, MgSO4·7H2O20g/L, alanine 3.8g/L prepare painted electrolyte.At temperature 25 DEG C, aluminum alloy sheet is carried out ac electrolytic coloring, after surface electrolyte is removed in then washing, immersion, last hot water sealing treatment.The coloring liquid color of alternating current electrolysis aluminium alloy attachment under different time with voltage using alanine chelating agent is identical with table 2.
Emphasis consults Fig. 1, Fig. 1 is the high resolution scanning Electronic Speculum figure in the aluminium alloy cross section of deposition Ag-Cu in porous oxide film prepared by the present invention (embodiment 2), show that in duct, miniature spherical granule is silver-bearing copper granule, and more uniform deposition is in duct, therefore uniform coloring, stable.
It is the X-ray energy dispersion spectrum with the aluminium alloy of deposition Ag and Cu in porous oxide film prepared by the present invention that emphasis consults Fig. 2, Fig. 2, and test is further characterized by duct have silver and copper.
High resolution scanning Electronic Speculum and X-ray energy dispersion spectrum test show, adopt exchange painted can make silver-bearing copper more uniform deposition in duct, therefore uniform coloring, stable.
The coloring liquid of the inventive method is made up of sulphuric acid, silver nitrate, copper sulfate, chelating agent etc., in the present invention, chelating agent A adopts a-amino acid, a-amino acid complex be analogy organic hydroxy-acid's class chelating agent more can effectively with the complex of silver ion complexation, the four-coordination coordination compound at five rings can be formed with silver ion, therefore the coloring liquid adding a-amino acid is highly stable, in preparation and (electrolysis) process of use, coloring liquid does not all have precipitate to produce, coloring liquid is highly stable, and coloring effect is excellent.The inventive method technique is simple, easy to operate, not only uniform coloring, stable, and improves the decay resistance of aluminium alloy, and the antibiotic and sterilizing rate of aluminium alloy reaches 99.0% again, and the feature such as it is long to have antibiotic and sterilizing acting duration, and coloring treatment cost is low.Aluminium alloy prepared by the present invention can as antibiotic and sterilizing material, for instance Medical wheelchair, go-cart, stretcher, bullet train and handrail and armrest in bus, door handle, balustrade, refrigerator etc., and building and ornament materials etc..
Coloring liquid life-time service does not have infusible precipitate to precipitate out, highly stable, as long as therefore regularly throwing in the material consumed, has both saved fund and resource, again environmental protection.
Although the foregoing describing the specific embodiment of the present invention; but those familiar with the art is to be understood that; we are merely exemplary described specific embodiment; rather than for the restriction to the scope of the present invention; those of ordinary skill in the art, in the equivalent modification made according to the spirit of the present invention and change, should be encompassed in the scope of the claimed protection of the present invention.