US20060130936A1 - Surface treatment of magnesium and its alloys - Google Patents

Surface treatment of magnesium and its alloys Download PDF

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Publication number
US20060130936A1
US20060130936A1 US10/526,961 US52696103A US2006130936A1 US 20060130936 A1 US20060130936 A1 US 20060130936A1 US 52696103 A US52696103 A US 52696103A US 2006130936 A1 US2006130936 A1 US 2006130936A1
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magnesium
polishing
brightening
magnesium alloy
alloy surface
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Ian Mawston
Serguei Panov
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Keronite International Ltd
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Magnesium Technology Ltd
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Assigned to MAGNESIUM TECHNOLOGY LIMITED reassignment MAGNESIUM TECHNOLOGY LIMITED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: PANOV, SERGUEI, MAWSTON, IAN GRANT
Publication of US20060130936A1 publication Critical patent/US20060130936A1/en
Assigned to KERONITE INTERNATIONAL LIMITED reassignment KERONITE INTERNATIONAL LIMITED ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MAGNESIUM TECHNOLOGY LIMITED
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
    • C25D11/02—Anodisation
    • C25D11/30—Anodisation of magnesium 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
    • 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
    • C23F3/02—Light metals
    • 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
    • C23F3/02—Light metals
    • C23F3/03—Light metals with acidic solutions
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
    • C25D11/38—Chromatising

Definitions

  • the present invention relates to surface treatment of magnesium and its alloys and in particular, though not solely, this invention relates to providing a bright shiny and/or textured surface finish to magnesium or magnesium alloy.
  • Magnesium metal is a highly reactive metal. In its usual fabricated forms the surface appearance is relatively dull and obscured by surface oxidation products or other compounds. Accordingly, magnesium metal does not usually manifest a bright, shiny, metallic finish except when the article has been machined. Although a dull surface may not always be disadvantageous, it is often desirable to provide a bright or polished surface to magnesium for reasons of aesthetics or utility. Owing to the reactivity of magnesium, post-treatments are generally necessary to passivate the surface, and conventionally the desired surface finish is lost during this step.
  • Techniques for applying paint to magnesium or its alloys comprise in the main pre-treatments such as chromating or non-chromating conversion treatments, followed by application of a paint.
  • the paint may be in the form of a powder coat, which is electrostatically applied then oven-cured, or a wet paint.
  • the painted surface may have a shiny finish, but it is not a finish that is comparable to a shiny metallic surface.
  • magnesium and magnesium alloys Two other problems exist that make the processing of magnesium and magnesium alloys difficult. Firstly, many commercial alloy articles (especially die cast articles) exhibit significant amounts of segregation both of the surface and in the interior of the article. This together with commonly encountered casting defects produces a highly inhomogeneous surface which cannot be improved by conventional means. Secondly, as magnesium is a highly reactive metal that forms a non-continuous oxide layer, for a viable bright surface finish to be attained the surface must be treated in a manner to prevent the oxide layer forming after surface brightening or polishing treatments. Traditionally such treatments include films or coatings which are opaque and/or are produced using heavy metals and other undesirable toxic chemicals.
  • the invention consists in a method of polishing and/or brightening a magnesium or magnesium alloy surface comprising the steps of:
  • the method comprises an initial step of pre-treating of said surface to remove surface contaminants.
  • said pre-treatment step comprises chemically etching said surface and/or degreasing said surface.
  • surface contaminants are removed prior during the pre-treatment step by contacting said surface with one or more degreasing components, such as sodium hydroxide.
  • degreasing components such as sodium hydroxide.
  • said chemical etching component comprises a nitric acid and/or phosphoric acid.
  • said pre-treatment step includes chemically blasting said surface.
  • said polishing step is carried out by a chemical polish and/or electrochemical polish while said surface is immersed in a polishing composition.
  • said chemical polish and/or electrochemical polish removes surface layers and/or reduces microscopic high points from the surface.
  • said polishing step is carried out by immersing said surface in a bath comprising one or more of the following components; a phosphoric acid solution, monopropylene glycol, ethylene glycol, and nitric acid.
  • a bath comprising one or more of the following components; a phosphoric acid solution, monopropylene glycol, ethylene glycol, and nitric acid.
  • said electrochemical polish is a galvanic electrolysis.
  • said electrochemical polish further includes the supply of an external voltage to said surface.
  • an electrolyte anti-stagnation means is utilised or an AC voltage is applied to the electrolyte containing said surface.
  • said electrolyte anti-stagnation means is an electrolyte stirrer and/or an ultrasonic wave generating means.
  • said polishing step is followed by an intermediary wash removing at least some of the chemical and/or electrolyte solution from said surface.
  • said intermediary wash is carried out in a composition containing monopropylene glycol and/or ethylene glycol.
  • said polishing step and/or said intermediary wash is followed by an alkaline wash.
  • said alkaline wash is carried out in a composition containing sodium hydroxide.
  • said alkaline wash substantially neutralises acids and/or substantially removes Aluminium, Manganese or Zinc from said surface.
  • said passivating step provides a substantially corrosion resistant and/or water insoluble surface coating or film.
  • said substantially corrosion resistant and/or water insoluble surface coating or film is a phosphate salt coating or film.
  • an inorganic material coating or sealer is applied to said substantially corrosion resistant and/or water insoluble surface coating or film.
  • said inorganic material coating or sealer is substantially transparent and/or substantially provides corrosion protection and/or at least some protection from mechanically induced damage.
  • said inorganic material coating or sealer is a silicon based composition, such as a disodium metasilicate, and a polyacrylamide coagulant in de-ionised water.
  • said passivating step and/or said inorganic material coating or sealer step is followed by a surface drying step.
  • a chemical blasting step comprises the steps of:
  • said activator is a solution selected from the following; ferric chloride, hydrochloric acid, ammonium bifluoride, and ammonium bromide.
  • said etch composition is selected from the following; ferric chloride; ferric chloride and phosphoric acid solution, or a reduced solution of ferric chloride and phosphoric acid.
  • said iron removal composition is selected from the following; nitric acid and sodium borate in solution, or nitric acid and phosphoric acid in solution.
  • said step of washing said surface is carried out with a water wash or an alkaline wash.
  • FIG. 1 illustrates a process flow diagram of various process steps of one embodiment according to the present invention
  • FIG. 2 illustrates a passivation cell configuration of an embodiment according to the present invention.
  • a set of method steps for chemically and/or electrochemically brightening or texturing also termed “polishing” herein) the surface of articles composed of magnesium or its alloys are described herein.
  • the following description is accordingly given by way of example only and it should be appreciated that a number of functional equivalents can be substituted for the compositions.
  • FIG. 1 a flowchart of various steps involved in the polishing and/or brightening of a magnesium or magnesium alloy surface is shown.
  • pre-treat steps 1 to 4
  • magnesium or magnesium alloy articles Prior to processing, it is usually appropriate to pre-treat (steps 1 to 4 ) magnesium or magnesium alloy articles to clean and prepare the surfaces for brightening or polishing.
  • the treatment depends on alloy, and the most preferred treatments are summarised below for some common alloys and forming processing. Alternative treatments may be possible and in some cases, depending on the original surface condition of the article, the omission of one or more steps may be possible without adverse effect on subsequent processing steps.
  • This invention discloses a means for processing and treating magnesium or magnesium alloys to preferably generate cosmetically acceptable bright textured surfaces which may be overlaid with an inorganic, transparent and/or corrosion resistant film.
  • Table 1 examples of possible compositions (or process solutions and preferred operating conditions) for the surface treatment processing steps, subsequently to be described are set out.
  • Table 2 illustrates possible pre-treatment process steps (and operating conditions) for a number of commonly utilised alloys.
  • Table 3 provides a useful summary of some combinations of process steps (from Table 1) and their sequencing for treating the surface of magnesium or magnesium alloys.
  • Ferric nitrate Fe(NO 3 ) 3 .9H 2 O - 0.1 mol/l Potassium fluoride (KF) 0.07-0.15 mol/l
  • Chemical blast CB1 Ferric chloride FeCl 3 ) - 0.12 mol/l Ambient solution Phosphoric acid (H 3 PO 4 ) - 0.8 mol/l Improved chemical CB2A Ferric chloride (FeCl 3 ) - 0.16 mol/l Ambient blast Solution Hydrochloric acid (HCl) - 0.05 mol/l Ammonium bifluoride (NH 4 HF 2 ) - 0.06 mol/l Ammonium bromide (NH 4 Br) - 0.17 mol/l
  • references to concentrations and temperatures are illustrative examples only of values which provide a preferred surface finish.
  • the processes operate over a range, both of concentrations and temperatures.
  • substitutions may be made for chemical constituents; for instance, ethylene glycol may be used in place of monopropylene glycol.
  • the magnesium or magnesium alloy article surface may be polished to a bright or metallic finish (step 6 ), or may be chemically “blasted” by a selective etch in step 5 to give a substantially light, textured finish similar to shot blasting.
  • the method of producing these finishes is fundamentally similar in most cases and may be summarised in Table 3.
  • FIG. 1 should be read in conjunction with the foregoing tables for details of times, temperatures and process solutions applicable to each step.
  • the examples also provide illustrative details of how various alloys may be treated according to the present invention.
  • the initial method described below may have particular application to high aluminium content alloys (for example, alloys containing greater than about 3% by weight of aluminium). Although the overall concept remains similar for low aluminium content alloys (for example, less than about 3% by weight), the surface finish may not be as effective as that obtained by the low aluminium content polishing and/or brightening method also described below.
  • a process of chemical or electrochemical selective etching 3 accomplishes the removal, from the surface being treated, of discontinuities and severe alloy component segregation. This process may also impart a somewhat controllable altering to the texture of the surface.
  • the term “etched” may be interchangeable replaced by “chemically blasted” (CB).
  • CB chemically blasted
  • the word “etched” may be reserved to describe processes as used in the pre-treatment (steps 1 to 4 in FIG. 1 ) phases only.
  • An electrochemical process using a modified phosphoric acid electrolyte may be able to “micro-polish” the surface to a high degree of brightness.
  • the “electropolish” step 6 illustrated in FIG. 1 and further described in Table 3 may involve two separate treatments that may be conducted in one process vessel.
  • the first of these may be a “galvanic polish” in which the article is short-circuited to a copper counter-electrode immersed in the EP3/EP4 (composition given in Table 1) solution. During the galvanic polish there is no externally imposed current.
  • a second, and optional treatment may be conducted during the electro-polishing and may comprise the imposition of an AC voltage, at about 5 VAC.
  • the current may not be controlled and may therefore reach a value that depends on the surface area of the work being processed and the characteristics of the surface and alloy.
  • a current density of 750 to 1,500 A/m 2 may be expected.
  • a copper counter-electrode may be used in the electro-chemical cell/bath.
  • a non-damaging method for the removal of electrolyte(s) from the surface after the electro-chemical polishing step 6 may be made possible by washing the surface with a suitable electrolyte removal component in step 7 .
  • a suitable wash may be a monopropylene glycol or ethylene glycol.
  • Step 7 may then be followed by an alkaline wash step 8 to neutralise any acids and further remove any electrolyte from the surface.
  • Step 8 may then be followed by rinsing the surface with de-ionised water in step 8 A prior to the surface being treated in the passivation step 9 .
  • the resulting treated surface may then be passivated in step 9 by the anodic deposition of a transparent corrosion resistant film upon the surface, in which the deposition thickness may be controllable.
  • a suitable corrosion resistant film may, for example, be a phosphate salt film, and such a salt may be a preferred film as a result of its useful corrosion resistance properties such as water insolubility and being slightly alkaline.
  • the thickness of this deposited film may be varied to provide increased corrosion resistance, as well as altering the final surface finish to provide a variety of surface finishes, for example, a bright shiny surface (a thin layer of film), a metallic slightly dulled surface finish (a thicker layer of film than the bright shiny finish), and a “pearl-type” surface finish (a thicker layer of film that the metallic finish).
  • the thickness of the film is of the order of about 100 nm, although it should be noted that the thickness of the film should preferably not be around one quarter of the wavelength of visible light as interference effects will occur.
  • Passivation of the brightened, metallic or chemically blasted surface may be undertaken chemically, using either of PM1 or PC1 described in Table 1 or by means of an electropassivation step.
  • a DC voltage source of approximately 10-20 volts may be applied to the article to be passivated, which is made the anode of a circuit in a solution 14 of about 2% ammonium bifluoride (NH 4 HF 2 .2H 2 O) at ambient temperature, for about 30 seconds (refer to FIG. 2 for the setup).
  • An Aluminium alloy counter-electrode 15 having at least twice the surface area of the article 13 being passivated may be employed.
  • Articles to be passivated are connected to a conductive busbar which is made the anode of an electrochemical cell.
  • Such electro-passivation methods may preferably avoid the use of heavy metals and provides substantially useful corrosion resistance.
  • De-ionised rinse step 10 may follow the passivation step 9 in order to remove any passivation composition components, and may then be followed by a drying step 11 , which may be an air drying process. It may be desirable that a hot air dry process is employed.
  • this passivated surface may be treated with an inorganic, transparent and substantially corrosion resistant film, such as a solution formed by combining disodium metasilicate, a polyacrylamide coagulant and de-ionised water (IS 1 —see below).
  • an inorganic, transparent and substantially corrosion resistant film such as a solution formed by combining disodium metasilicate, a polyacrylamide coagulant and de-ionised water (IS 1 —see below).
  • these deposits can be controlled to give different deposition sizes and patterns.
  • a series of pits and ridges remain on the metal surface.
  • a surface that has a more regular geometric pattern has now replaced the original metal surface (with random defects). Hence the appearance is enhanced.
  • the metal surface becomes microscopically smoother and hence more reflective or brighter.
  • the galvanic method is supplemented by the imposition of an AC current at certain stages. This is done to assist in breaking diffusion stagnation and to remove surface contamination.
  • This is basically a bath of pure mono-propylene glycol or ethylene glycol run either cold or moderately hot to act as an intermediary wash between strong phosphoric acid solutions and the alkaline wash solution. This is used so that the neutralisation reaction is less violent and may prevent the rapid stain-producing attack of dilute phosphoric acid on magnesium alloys. Accumulated water and acid in this solution can be controlled by external treatment.
  • An inorganic sealing step is used to deposit a clear Silicon (Si) based coating over anodised or passive bright magnesium or alloy components.
  • the coating is applied by dipping or by spraying and by adjustment of the conditions different film thicknesses can be obtained.
  • the inorganic seal is advantageously substantially transparent and gives the substrate good protection against corrosion and mechanical damage. It can be used effectively over only a limited number of dye coloured anodised magnesium substrates as there can be a colour shift due to the high pH of the inorganic seal or in some cases the dye can be destroyed.
  • a limited number of colours can be applied to bright surfaces so that the metallic lustre is preserved. This is done by establishing a very thin ( ⁇ 100 nm), transparent film of Magnesium Oxide (MgO) on the bright substrate by a variety of means. It can then be dyed by a modified procedure using standard Aluminium (Al) dyes.
  • MgO Magnesium Oxide
  • non-anodised finishes are defined as decorative finishes that are non-opaque and largely reveal the substrate metal.
  • the appearance can be further sub-classified as bright, metallic, pearl, etc and the texture of the substrate may be classified as flat, brushed, etched etc.
  • the texture of the substrate may be classified as flat, brushed, etched etc.
  • the appearance is a “metallic” finish.
  • the result was a very bright finish, having a slight yellow tinge.
  • the die cast structure was plainly visible.
  • the result was a metallic finish in which casting structures were visible.
  • a die cast plate of AM50 alloy having the same dimensions as that in examples 1 and 2 above, was treated using the following processes:
  • a rolled flat plate, of AZ31B alloy, 110 mm ⁇ 80 mm, 1 mm thick was pre-conditioned so that it was clean of sundry corrosion and dirt. It was then processed as follows:
  • the result was a mirror bright finish.
  • the plate was then passivated by an electrochemical treatment. It was immersed in a solution of 2% ammonium bifluoride (NH 4 HF 2 .2H 2 O) which was contained in a plastic tank with attached stainless steel plates on each side. These were connected to the negative terminal of a suitable power supply while the article itself was attached to a bus-bar that was connected to the positive terminal. After twenty seconds, the power was switched on and maintained at around 15 VDC ( ⁇ about 1 VDC). Upon the application of the electric current the article became noticeably brighter. There was no gas evolution. Initially the current was 20 Amps, but this decayed to around 1 Amp after about 5 seconds and finally to about 0.3 Amps after about 30 seconds.
  • 2% ammonium bifluoride NH 4 HF 2 .2H 2 O
  • the process may be modified to provide an optimised or superior treatment for low aluminium content magnesium alloys, preferably magnesium alloys containing approximately 3% aluminium (by weight) or less.
  • this alternative surface treatment process works well with the fine-grained AZ31 alloy in either rolled sheet or extrusion form.
  • EP4 new additional process solution tailored to the special requirements of fine-grained AZ31 alloy in either rolled sheet or extrusion form has been developed for low electropolishing low aluminium content magnesium alloys.
  • the process including EP4 solution is superior to the above described high Aluminium content method as it has fewer process steps, superior finish, reduced cost and preferably uses less energy intensive process conditions.
  • the finished material When used in conjunction with previously defined post treatments, for example passivation, the finished material has a more aesthetic appearance and is more corrosion resistant than previously obtainable when surface treating low Aluminium content magnesium alloys using the above described high aluminium content method.
  • the process can be used with greater simplicity alongside the surface texturing or polishing process.
  • compositions shown are for 1 litre of solution.
  • the FRS2 solution (which may for example be an iron removal solution) may be used to prepare the surface for subsequent treatment.
  • the use of mixed acids in the polishing step may be used; compared to generally phosphoric acid only in the previously mentioned process for magnesium alloys having an Aluminium content of approximately 3% (by weight) or greater; together with a carrier solvent, such as monopropylene glycol (MPG).
  • MPG monopropylene glycol
  • Phosphoric acid and predominantly nitric acid may comprise the preferred mixed acids utilised for the polishing step with low aluminium content surfaces.
  • the phosphoric acid is consequently now used as a catalytic component, rather than as a major consumable component, such as the nitric acid component.
  • the polishing step using the EP4 solution may also be operated at approximately room temperature ( ⁇ 20° C.); although it is appreciated that variation in the operating temperature may increase or decrease the rate of the surface treatment steps.
  • the components of the polishing step are consumed at lower rates, which may result in reduced frequency of polishing solution replenishment.
  • the requirement of an AC supply in the AC electrochemical polishing step 6 becomes optional as the combined mixed acid and MPG provide sufficient polishing of the surface.
  • the intermediary wash step 7 for example using MPG as previously described in the process above is also no longer required, and advantageously it may be that any “washing marks” resulting from the previously described intermediary process are also eliminated.
  • Steps 1 to 4 may be omitted although in some cases an etching pre-treatment step may be required to remove any external protective coating from the surface.
  • Surface Texturing Heavy chemical blasting 1.
  • Water wash Mild chemical blasting 1.
  • Water wash Surface Polishing Treatments 1. Chemical polishing in EP4 solution 20-90 s 2. Washing in CW10 15-45 s 3. Water wash Post-treatment 1. Passivation (BPT1, voltage according to desired finish) 2. Water wash 3. Dry An Experimental Set-Up
  • a brightening process was trialled and was conducted in a 2000 ml beaker at 20 to 30° C. in EP4 solution.
  • the bath was stirred with a mechanical stirrer and its temperature recorded.
  • the brightness of the finished plates were monitored and some plates were passivated in BPT2 solution to obtain either bright, metallic or pearl finishes to assess this process.
  • This process has proven to be capable of producing excellent results on fine-grained AZ31 sheet in a very consistent manner.
  • the process is simple, has few steps and utilises relatively low cost chemicals and simple low cost plant and equipment.
  • the process is easily managed using simple laboratory tests.
  • Step E1 Step No. Operation Chemicals Temp. ° C. Time min 1 Degrease* DGA 70-80 5 2 Water rinse* Tap 15-50 0.5-1 3 Phosphoric PE3 15-35 0.5 etch 4 Water rinse Tap 15-50 0.5-1 5 Alkaline wash DGA 70-80 1-1.5 6 Water rinse Tap 15-50 0.5-1 *These steps can be omitted if metal surface does not have lubricants
  • Step X1 Step No. Operation Chemicals Temp. ° C. Time min 1 Activation CB2a 30-40 0.3 2 Chemical blast CB1 (CB1a) 30-40 1-5 3 Alkaline wash CW25 70-80 5 4 Water rinse Tap 15-50 0.5-1
  • Salt spray testing was conducted on samples of AZ31 alloy sheet or extrusion which had been brightened or polished according to the above described low Aluminium content method to determine resistance to corrosion.
  • Sample Preparation The samples were prepared using following technique: 1. No pre-treatment for clean metal (sheet or extrusion) 2. Surface cleaning by FRS2 solution (Spectrolite sheet) 3. CB2A* 20 s 4. CB1A (heavy blasting) or CB3 (mild blasting)* 3 min 5. FRS2* 2 min 6. EP4 1 min 7. CW10 15-30 s 8. Water wash 9. BPT1 1 min 10. Water wash 11. Drying 12. Acrylic powder coating# *For CB finishes only #When required
  • Corrosion was caused by uneven powder coating CN8 AZ31, Coarse BPT1 Powder coating 48 Heavy filiform extrusion CB, corrosion bright, Sample had CB2A + imperfect powder CB1a coating: brown colour on the top of CB hills CN9 AZ31, Flat, BPT1 Powder coating 48 Heavy bottom extrusion bright corrosion.
  • Relatively low corrosion resistance of bright passivated AZ31 alloy presumably is due to uneven powder coating (extrusion) and small thickness of plates (0.8 mm sheet). The latter produced centres of corrosion on the sample edges.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Electrochemistry (AREA)
  • ing And Chemical Polishing (AREA)
  • Printing Plates And Materials Therefor (AREA)
  • Chemical Treatment Of Metals (AREA)
US10/526,961 2002-09-09 2003-09-09 Surface treatment of magnesium and its alloys Abandoned US20060130936A1 (en)

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PCT/NZ2003/000200 WO2004022818A1 (en) 2002-09-09 2003-09-09 The surface treatment of magnesium and its alloys

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CN106404477A (zh) * 2016-08-23 2017-02-15 中国航空工业集团公司北京航空材料研究院 一种用于粉末高温合金电子背散射衍射分析的制样方法
DE102017222932A1 (de) * 2017-12-15 2019-06-19 Zf Friedrichshafen Ag Chemisch unterstützte Feinstbearbeitung
DE102018218393A1 (de) * 2018-10-26 2020-04-30 Aesculap Ag Verfahren zum Oberflächenbehandeln eines Metall- oder Legierungsprodukts sowie ein Metall- oder Legierungsprodukt
CN111893468A (zh) * 2020-07-05 2020-11-06 江苏荣企新材料科技有限公司 一种铝镁合金金属框架表面抗腐蚀处理工艺

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3222266A (en) * 1958-08-20 1965-12-07 Kaiser Aluminium Chem Corp Method of enameling anodized aluminum
US3766030A (en) * 1971-12-27 1973-10-16 Muroc Prod Corp Method of electropolishing
US4578156A (en) * 1984-12-10 1986-03-25 American Hoechst Corporation Electrolytes for electrochemically treating metal plates
US5683522A (en) * 1995-03-30 1997-11-04 Sundstrand Corporation Process for applying a coating to a magnesium alloy product
US6319819B1 (en) * 2000-01-18 2001-11-20 Advanced Micro Devices, Inc. Process for passivating top interface of damascene-type Cu interconnect lines
US6335099B1 (en) * 1998-02-23 2002-01-01 Mitsui Mining And Smelting Co., Ltd. Corrosion resistant, magnesium-based product exhibiting luster of base metal and method for producing the same
US6596150B2 (en) * 1998-05-28 2003-07-22 Fuji Photo Film Co., Ltd. Production method for an aluminum support for a lithographic printing plate

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19744312A1 (de) * 1997-10-07 1999-04-08 Volkswagen Ag Verfahren zum Verbinden von wenigstens zwei Fügepartnern aus einem Magnesiumwerkstoff
DE19800035A1 (de) * 1998-01-02 1999-07-08 Volkswagen Ag Verfahren zum Fügen von mindestens zwei Fügepartnern
JP2000219975A (ja) * 1999-01-28 2000-08-08 Nippon Parkerizing Co Ltd 表面処理されたＭｇ合金およびその表面処理方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3222266A (en) * 1958-08-20 1965-12-07 Kaiser Aluminium Chem Corp Method of enameling anodized aluminum
US3766030A (en) * 1971-12-27 1973-10-16 Muroc Prod Corp Method of electropolishing
US4578156A (en) * 1984-12-10 1986-03-25 American Hoechst Corporation Electrolytes for electrochemically treating metal plates
US5683522A (en) * 1995-03-30 1997-11-04 Sundstrand Corporation Process for applying a coating to a magnesium alloy product
US6335099B1 (en) * 1998-02-23 2002-01-01 Mitsui Mining And Smelting Co., Ltd. Corrosion resistant, magnesium-based product exhibiting luster of base metal and method for producing the same
US6596150B2 (en) * 1998-05-28 2003-07-22 Fuji Photo Film Co., Ltd. Production method for an aluminum support for a lithographic printing plate
US6319819B1 (en) * 2000-01-18 2001-11-20 Advanced Micro Devices, Inc. Process for passivating top interface of damascene-type Cu interconnect lines

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050211052A1 (en) * 2004-03-29 2005-09-29 Gigliotti Patrick J Guitar having a metal plate insert
US20110097573A1 (en) * 2009-01-09 2011-04-28 Nobuyuki Okuda Magnesium alloy structural member
CN102277611A (zh) * 2010-06-09 2011-12-14 株式会社Nuc电子 用于处理镁基金属的表面以给予其金属纹理的方法
US20110303545A1 (en) * 2010-06-09 2011-12-15 Nuc Electronics Co., Ltd. Method for treating surface of magnesium-based metal to give metallic texture thereof
CN102198626A (zh) * 2011-05-11 2011-09-28 北京科技大学 一种镁合金板带卷单、双面抛光装置
US20130081951A1 (en) * 2011-09-30 2013-04-04 Apple Inc. Laser Texturizing and Anodization Surface Treatment
US9644283B2 (en) * 2011-09-30 2017-05-09 Apple Inc. Laser texturizing and anodization surface treatment
US10612118B2 (en) 2012-04-25 2020-04-07 Arcelormittal Methods for producing a pre-lacquered metal sheet having Zn—Al—Mg coatings and corresponding metal sheet
CN102944455A (zh) * 2012-10-24 2013-02-27 郑州飞机装备有限责任公司 辨别锻铝2a14纵向纹路的方法
CN104131294A (zh) * 2014-07-01 2014-11-05 蚌埠市高华电子有限公司 一种具有抗菌效果的铝及铝合金混合抛光液及其制备方法
CN110257838A (zh) * 2019-07-02 2019-09-20 佛山市南海区尚铭金属制品有限公司 铝型材喷粉前处理工艺

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