TW544474B - Surface treatment method for magnesium alloys and magnesium alloy members - Google Patents

Abstract

The present invention provides a surface treatment method for magnesium alloys that can form a uniform, fine, and dense conversion coating on a magnesium alloy surface on which mold release agent, an oxide layer, and an alloying component (e.g., aluminum and zinc) segregation layer are potentially present, and also provides magnesium alloy members whose surface has been treated by the aforesaid surface treatment method. The surface treatment method of the present invention comprises a degreasing process to degrease the surface of the magnesium alloy, a chemically etching process to chemically etch the alloy, and a conversion treatment process to form a conversion coating. The chemical etching forms a magnesium phosphate coating having a coating weight of 10 to 2,000 mg/m<2>, measured as phosphorus, by bringing the surface of the magnesium alloy into contact with an aqueous solution containing a phosphoric acid-type compound.

Description

544474 A7 B7 Printed by the Consumer Cooperative of the Ministry of Intellectual Property of the Ministry of Economic Affairs of Japan 5. Description of the invention ([Detailed description of the invention] [Technical field to which the invention belongs] Film attached: Γ is related to the superior corrosion resistance and surface of magnesium alloys A novel surface treatment method for coating, and a magnesium alloy component that has been surface-treated by the surface treatment method. [Known Technology] ^ Most metal material components used in alloy steam, etc. Gold) is required for durability or aesthetics, and is then coated and used after various surface treatments are applied to the disc. The purpose of surface treatment is to remove contaminants such as cutting oil remaining on the surface of the raw material, so as to form a precise chemical surface treatment film, which can impart purity resistance and coating film adhesion. * In recent years, it was learned from the purpose of global environmental conservation that there is a tendency to apply magnesium alloys, which are the lightest and most recyclable magnesium alloys among metals. For example, in the area of car A, from the weight reduction of vehicles for the purpose of increasing fuel costs, to the use of steel or aluminum alloy components are starting to apply to magnesium alloys. In the field of home appliances, there is a tendency to migrate from conventional plastics to magnesium alloys with excellent recyclability, centered on the frame of a notebook computer or a mobile phone. Most of these magnesium alloy members are formed by a thix⑽ouiding method called a die casting method. These casting methods use high speed and high pressure to inject molten or semi-fused magnesium alloy into a mold and preform it, and are characterized by superior scale accuracy or superior productivity. Depending on the product, it can also be used for forming by the compression molding method or forging method of the magnesium alloy sheet for stretching. The relevant magnesium alloy components are the same as those of steel or aluminum alloys. The paper size applies the Zhongguanjia Standard (CNS) A4 specification ⑵G X 297 public love 544474 A7, the description of the invention () after the surface treatment is applied. . Magnesium alloys are active and easy to corrode among practical metals. Therefore, in the case of steel or aluminum alloys, the surface treatment step is to form a delicate and uniform metal surface: it is important to treat the f film system. . However, magnesium alloys are also extremely difficult to form chemically-treated coatings on delicate and uniform metal surfaces. This is due to the chemical unevenness of the magnesium alloy surface. &lt; In the following, chemical unevenness of the surface of the magnesium alloy is described in detail. Generally, in magnesium alloys used in motorcycles, home appliances, etc., in order to improve the properties such as formability, branch strength, and malleability, a large amount of gold components such as succinct, succinct, and fierce are added. For example, AZ91, the most common magnesium alloy for foundry, is added with %% gold and zinc! %. In the surface treatment step of performing a chemical reaction and forming a chemical treatment film on the metal surface, the formation of these alloys in the raw material often has a great influence on the surface treatment properties. In order to form a dense i-surface chemical treatment, the composition of the turning alloy should be dense and uniformly distributed in the original material. However, in the town alloy components formed by the mold, alloy components such as Shao and zinc are not uniform; 3 In the original material, there are many cases of segregation. Here, the segregation of the magnesium alloy will be described in detail. = The distribution of impurities or alloy components in the genus becomes uneven :: It is the most common cause of segregation when it is suspected, such as the use of die-casting or contact, wheat, and forming, which is close to the original mold Since the solidified part (near the overflow part) is initially solidified, the purity is high. However, the solidified part (gate part: near) later has a higher concentration of impurities or alloy components. In the center 4 of the thick part of the product, although the final phase 'alloy composition segregates at a very high concentration, Ding Guoguo ⑵〇x 297 public love is applicable to 1 piece of paper 3 (Please read the precautions on the back first) (Fill in this page) # Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs --- U ----------------------------- 544474

In the casting method or thixoforming method, pressure will be applied during the solidification after injection, and the liquid phase with high concentration segregation of the alloy components will be drilled from the solid phase. This type of segregation is called macrosegregation. On the other hand, when the metal structure of a magnesium alloy is observed, it is an α-phase 'composed of high-purity magnesium and a cold phase of an intermetallic compound composed of an alloy component, such as Mgl7A112. This phase is not evenly distributed in the raw material, and it is mostly segregated at the grain boundary. This type of segregation is called microsegregation. As mentioned above, macrosegregation and observed segregation can show various behaviors regardless of the cooling rate or pressurization conditions at the time of prayer. Therefore, even alloys of the same composition depend on the shape or location of the component, casting conditions, etc. Different, the degree of deflection or the metal structure is also different, so the surface system is chemically non-uniform, and it is more difficult to chemically treat the film system to form a dense and uniform metal surface. As for the surface treatment method of magnesium alloy, generally, the three types of treatment steps shown below are applicable. (Processing step 1) Degreasing—water washing—metal surface chemical treatment—water washing 4 pure water washing—drying (processing step 2) degreasing—water washing—chemical etching—water washing—metal surface chemical treatment—water washing—pure water washing Θ drying (processing step 3) Degreasing-Washing-Chemical rice carving-Washing-Smut treatment-Washing-Chemical treatment of metal surface-Washing-Pure washing-Drying 6 (Please read the precautions on the back before filling this page) Bureau of Intellectual Property, Ministry of Economic Affairs The paper size printed by the employee consumer cooperative is applicable to the Chinese National Standard (CNS) A4 (2) 0 X 297 mm. One bite, &lt; · ϋ ϋ ϋ — ^ 1 I ϋ Hi I ϋ n I ϋ n ϋ · ϋ I ϋ n ϋ n ϋ ϋ ί ί ϋ ϋ ϋ 544474 A7 V. Description of the invention (Printing and cutting of two fats by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, etc.) The two steps are to remove mechanical oil, remove mechanical oil, cutting oil, etc. Huaxun's I-degree organic scale is used for the purpose of simultaneous release of the release agent or the most visible sound of the deflection layer and the hydroxide layer. The σ step next to you is to remove the chemical treatment step χ V Dirt that has remained on the surface, that is, The purpose is to produce impurities, or residues that have been thickened on the surface, and the like. The chemical treatment on the metal surface is to form a metal surface chemistry such as chromate chromate or sulfonium diacetate. The film is treated for the purpose of improving the corrosion resistance and the adhesion of the coating film. 1. These processing steps can be used separately according to the required performance of the surface treatment or the degree of pollution of the surface. For example, a large amount of the release agent is attached The component is suitable for (Processing Step 2) or (Processing Step 3), while the component with a small amount of release agent is suitable for (Processing Step 1). So far, the method related to the aforementioned surface treatment method There are several reports and opinions; it is being proposed. Those related to chemical treatment liquids on metal surfaces can be roughly divided into treatment liquids containing hexavalent chromium (chromate) and treatment liquids without hexavalent chromium (non-chromic acid) Salt). Regarding the treatment liquid containing hexavalent chromium, the treatment liquid developed by the American Dow Chemical Company is widely known and has reached the stage of practical application. For example, "chromic acid treatment liquid (D. wl method ) "," Dichromic acid treatment solution (Dow7 method) "," Experimental dichromate treatment solution (dow 9 method) "," Manganese chromate treatment solution (D0W2 2 method) ", etc. It is less affected by the dispersion of the surface than the car driver, and the property of the property and the adhesion of the coating film is superior. However, the hexavalent chromium contained in these treatment liquids is harmful to the human body. This paper applies the Chinese National Standard (CNS) A4. Specifications (210 X 297 mm) ------------ # / (Please read the precautions on the back before filling out this page) One 5, · n H ϋ —Γ ϋ ϋ ϋ II ϋ II ϋ ϋ ϋ ϋ n ϋ II n ϋ nnn 1 · ϋ ϋ H ϋ-544474 A7, the description of the invention (), the treatment liquid system containing no hexavalent chromium is expected. With the use of related treatment liquids, it is more difficult to be affected by the surface dispersion, and a surface treatment method that can further obtain a surface with superior corrosion resistance and coating film adhesion is expected. Yes, no: Most of the inventions of hexavalent chromium metal surface chemical treatment fluids have been reported. For example, a method of "corrosion treatment of magnesium alloy members by applying a corrosion inhibitor containing at least one selected from nitric acid, sulfuric acid, and phosphoric acid to a member to form a recording-resistant protective film (Japanese Patent Publication No. 5-58〇73i) ", At least one organometallic compound derived from a metal alkoxide, a metal acetoacetone ester, and a metal carboxylic acid, and has any of an acid, a base, and a salt, or any of One of the organic compounds is selected ^ At least one "method for surface treatment of a metal (referred to as" Takkaikai Hei 9-228062. ") Formed by at least one coating-forming aid, and the surface of the magnesium alloy member is plated with organic acids or organic acids. The reaction of the aqueous solution of the soluble salt begins with the "surface special property of magnesium alloy components" published in the "metal surface of magnesium alloy components" of the insoluble salt of the town metal surface magnesium and the organic acid. "High-resistance clay formation method for lock alloy materials (Japanese Patent Application Laid-Open No. 9_24338)", "fluorine compounds, coating formation aids, nickel ions, ionization = ionization = concentration aqueous solution treatment"水水 、 玄 ^ 有 眉 # / 孤To>, an aqueous solution of magnesium-based compounds: r, etc., table, liquid system no matter which material is used to m 8

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Line I 544474 A7 B7 V. Explanation of the invention (problem of printing by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. In addition, inventions related to the degreasing agent used in the degreasing step and the etchant used in the chemical money engraving step are also reported. For example, in an aqueous solution containing a specified amount of persulfate, at least one of "magnesium-magnesium alloy acid bath" (Japanese Patent Application Laid-Open No. 53-102231) added with at least one selected from sulfuric acid, hydrochloric acid, nitric acid, or oxalic acid, After pickling the ballast alloy, the method of "removing dirt from the surface of magnesium alloys" (Japanese Patent Application Laid-Open No. 6— 220663) "etc. These inventions are for the purpose of etching the surface of magnesium alloys to remove mold release agents, oxide films, and alloy deflections. However, even if these methods are applied, it is intended to form a dense and uniform magnesium surface. It is difficult to chemically treat the metal surface, and it is difficult to obtain superior corrosion resistance and coating film adhesion. [Problems to be Solved by the Invention] Therefore, the present invention The person who solved the above-mentioned problems has specifically provided a magnesium alloy having a dense and uniform surface formed on the surface of the magnesium alloy existing on the release layer, the oxide layer, and the deflection layer of aluminum or other alloy components. For the purpose of chemically treating the coating on a metal surface, a surface treatment method of a magnesium alloy imparting superior corrosion resistance and coating film adhesion, and a magnesium alloy member subjected to surface treatment by the surface treatment method can be obtained. (Please read the precautions on the back before filling out this page)-Order l. The present inventors have carefully reviewed the measures adopted to solve the problems of the above-mentioned conventional technology, and the results were engraved on the chemical surname. Steps: contact the surface of the magnesium alloy with an aqueous solution containing a phosphoric acid-based compound;

-Line ·· &quot; ----------------------- 544474 A7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs The oxide layer and the deflection layer of the alloy composition also form magnesium phosphate at the same time: the coating film—a person can form a sensitive, uniform and uniform metal surface chemical treatment film on the surface by chemically treating the metal surface. Solve the aforesaid problem, and even complete the present invention. The second method is the surface treatment method of the magnesium alloy of the present invention, which is a step of degreasing the oil containing grease on the surface of gold, and the chemical step of chemically engraving. Xiang metal The surface treatment method of the chemical treatment step of the pure metal surface is shown in the table below. The chemical engraving step is to contact the surface of the aforementioned magnesium alloy with a water-soluble compound containing a phosphoric acid-based compound. The step of coating with magnesium phosphate is characterized by the use of a casting method called die-casting, thixoforming, mold processing, or forging. The surface of a town-alloy member formed by M is attached during casting, Release agent applied to the mold, and The inscription of alloy composition or the segregation of alloy composition such as zinc, manganese, etc., and the reaction with oxygen in the air makes the oxide film more = chemically non-uniform surface such as growth is more common. Therefore, "the person makes dense__ _Munju ’s metal surface is chemically treated with a film to provide superior resistance to recording and coating. _The coating system is particularly effective. 至 'As for the aforementioned chemical etching step, the aqueous solution containing a phosphoric acid-based compound * contains orthophosphoric acid from a phosphoric acid-based compound. At least one selected from the group consisting of phosphonic acid, pyrophosphoric acid, hydrazine trihydrate, and alkali metal salts thereof. The concentration of the phosphonic acid compound is in the range of 200 g / L, and the pH is in the range of 1 to 12. As for the aforementioned metal surface chemical treatment liquid, it contains at least orthophosphoric acid ------------ # ------ ^ — 定 卜 — ί ---- 线 丨 · ( Please read the notes on the back before filling this page.) This paper is used weekly. _ 豕 Standard (CNS) A4 Specification ⑵〇X 297 mm) 544474 Α7 Β7 Printed by the Consumers ’Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs Description of the Invention () 'and at least one selected from the group consisting of Zn, Mn and Ca An acidic aqueous solution of pH 2 ~ 6 of metal ions, or at least one fluorine compound selected from the group consisting of hydrofluoric acid, silicofluoric acid, hydrazone hydrochloric acid, and chimnic acid. Blood is composed of Mn, Mo, W, Ta Oxygen of at least one metal selected from the group consisting of Re, Nb, and V, and an acidic aqueous solution of a compound having a pH of 2 to 6. On the other hand, the magnesium alloy member of the present invention uses the above-mentioned surface of the town alloy of the present invention. The treatment method is characterized by surface treatment. [Implementation Modes of the Invention] The following is a detailed description of the surface treatment method of the magnesium alloy of the present invention (hereinafter, the single A is referred to as a "surface treatment method"). The surface treatment method of the present invention is applicable to a magnesium alloy member. The type of the magnesium alloy is not particularly limited, but examples include magnesium alloys for casting such as AZ91, Yan 60: ZK5; 1, ZK61, and magnesium alloys for extension such as AZ31, AZ61, and ZK60. The method for forming the magnesium alloy member is not particularly limited, but examples thereof include a die casting method, a thixoforming method, a compression forming method, and a forging method. Although the surface treatment method of the magnesium alloy of the present invention is based on the aforementioned (treatment step) "degreasing-washing-chemical ㈣ ~ m belongs to surface chemical treatment-washing-pure water washing-drying" as the basic, but the degreasing step, chemical etching The steps and the chemical treatment of the metal surface are necessary steps. The other steps are to properly set the surface of the alloy of the treated object and the "formation of extremely thick growth of the oxide film layer" contaminated by the surface of the alloy of the processed object, and the point of view to stabilize the film performance. Need to stab ^ Step 4) One thing is more appropriate. 1 treatment (treatment step 4) degreasing ~ water washing-(acid water soluble

II This paper size is applicable to China National Standard (CNS) M specification (210 (please read the precautions on the back before filling this page) ---- „----- ^ ----------- ----- 544474 A7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the invention () t Washing-Decontamination-Washing ~ Chemistry-Washing-Pure Washing-Drying-Washing-Metal Surface Chemistry Department mentioned above) (Processing step 4) "Remaining moment (acidic aqueous solution)" is the so-called "chemical instrument engraving ~ 者", and those who seek to use the acidic aqueous solution for the early soap, use the surface to dry "" ^^ 止 r / 乾 4 Towels, "use your water, clothes, etc., not an etching step (acid solution)" to distinguish. The following will be explained in the order of steps. [Degreasing step] 'Before the chemical etching step, degrease the surface of the magnesium alloy. By using the degreasing method, a dense and uniform magnesium phosphate film can be formed in the chemical money engraving step described later. The degreasing treatment in the degreasing step is performed by bringing the ball alloy of the object to be treated into contact with the degreasing solution. As a method for contacting the ballast alloy of the object to be treated with a degreasing solution, conventionally known methods such as impregnation and spraying can be used, and any method can be applied to the present invention (hereinafter, the term "contact" with each step) The concepts are the same). As for the degreasing solution that can be used in the degreasing step, it is sufficient if it can remove organic dirt, and its composition is not particularly limited, but an alkaline aqueous solution containing a surfactant is preferably used. As for the alkaline component of the relevant degreasing solution, hydroxides, dishates, silicates, carbonates, etc. of alkali metals are applicable. As the surfactant, any of nonionic, cationic, and anionic systems can be used. Furthermore, in order to improve the degreasing efficiency, an integrator may be blended. The temperature and time for bringing the degreasing solution into contact with the magnesium alloy are not particularly limited, but it depends on the degree of contamination on the surface of the magnesium alloy so that it is 35 ~ 70, 2 ~ 10 (please read the precautions on the back before filling this page) )-Order il — line 丨 parameter 丨 丨

II n H nnn ϋ-_ This paper size is applicable to the Zhongguanjia Standard (CNS) A4 specification ⑵Q χ 297 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 544474 A7 B7 V. Description of the invention () Contact within b minutes Better. The concentration of the degreasing solution is appropriately set according to the degree of contamination on the surface of the magnesium alloy and the composition of the degreasing solution. In addition, the surface of the magnesium alloy of the object to be treated is excessively contaminated by the release agent. When the oxide film grows extremely thick, a beading treatment may be applied to the surface of the magnesium alloy before degreasing. By bead blasting, the physical method V is used to remove the contaminants remaining on the surface of the aforementioned magnesium alloy. When the bead blasting treatment is applied, the degreasing using the above-mentioned degreasing solution may be omitted. However, when a bead blasting treatment has been applied, it is preferable to perform degreasing of the degreasing solution on the surface of the aforementioned magnesium alloy by the bead blasting treatment to the oil and the like attached to the abrasive or contained in the abrasive. Moreover, in the present invention, the process of applying each of the beading treatments is also included in the concept of degreasing. Therefore, as for the degreasing step necessary for the present invention, the process of applying each of the beading treatments includes a separate state, using the above degreasing solution. There are two types of degreasing alone, and two types of degreasing of the above degreasing solution after applying each of the bead treatments. [Remaining step (acidic aqueous solution)] As mentioned above, the surface of the magnesium alloy to be treated is excessively contaminated by the release agent, and the oxide film layer grows extremely thick. Before the chemical etching step described below, It is preferable to provide an etching step (acid aqueous solution). Through the etching step (acidic aqueous solution), the contaminants remaining on the surface of the aforementioned ballast alloy are chemically removed to completely clean the surface. The etching treatment in the etching step (acid aqueous solution) is performed by contacting the samarium alloy of the object to be treated with the acid aqueous solution. As for the acidic aqueous solution, if it can be decomposed to remove the aforementioned magnesium alloy surface __13_ This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page) Order- -l · ---- line—continued ----------------------- 544474 A7 Printed invention description by employee consumer cooperative of Intellectual Property Bureau of Ministry of Economic Affairs 'There is no restriction, but it is appropriate to apply sulfuric acid, nitric acid, and the foregoing combination of all = 4 is appropriate. Conditions such as the concentration of the acidic aqueous solution, the temperature, and the contact time between the surfaces are not particularly limited. = Equal =: The degree of pollution of the magnesium alloy is described. The formation of the acidic aqueous solution used can be appropriately adjusted. [Decontamination step] &quot; When performing the engraving treatment using the insect | step insect etch step (acid aqueous solution), the step t will remain on the surface of the aforesaid bonding gold, so it is appropriate to set the decontamination step on the decontamination step. The decontamination is performed by contacting the magnesium alloy of the object to be treated with the decontamination solution. As for the decontamination liquid, it is not particularly limited as long as it can remove the dirt that has remained on the surface of the aluminum alloy, but it can be applied with an aqueous solution of sodium hydroxide adjusted to pH 12 or higher, or containing Method for contamination from the surface of a magnesium alloy (Japanese Patent Application Laid-Open No. 6-220663), a strongly alkaline aqueous solution of the integrative component, etc. The conditions such as the concentration of the decontamination liquid, the temperature, and the contact time with the surface of the magnesium alloy are not particularly limited. The degree of adhesion of the contamination on the surface of the magnesium alloy, the components of the surrounding decontamination liquid Can be adjusted appropriately. [Chemical surname engraving step] The chemical surname engraving step is a step in which the magnesium alloy to be treated is brought into contact with an aqueous solution containing a scaly acid-based compound, and if the surface of the aforementioned magnesium alloy is cleaned, a film of magnesium phosphate is simultaneously formed. Therefore, for the benefit of the present invention (please read the note on the back? Matters before filling out this page) 0 Order: Line 丨 engine 14 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 544474 A7 B7 V. Description of the Invention (The treatment of chemical etching steps for printing by employees' consumer cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs and the treatment of acidic aqueous solutions commonly referred to as etching do not agree on the point of forming a film. By using each The chemical etching step can dissolve and remove the mold release agent, oxide layer, and segregation layer of the alloy components remaining on the surface of the magnesium alloy, and it is also possible to form a film of magnesium phosphate. The film formed on the surface of the magnesium alloy is also possible. The coating amount of magnesium phosphate is based on the amount of phosphorus, which is 10 to 2000 mg / m2, and more preferably 50 to 1,000 mg / m2. The coating amount of magnesium phosphate is based on the amount of phosphorus. When it is less than 10 mg / m2, the substrate is not sufficiently covered with the magnesium phosphate film, and the corrosion resistance and the adhesion of the coating film may be reduced. On the other hand, if it exceeds 2000 mg in terms of phosphorus adhesion amount / m2, the film As a result, the surface of the magnesium alloy is chemically non-uniform, and the coating of magnesium phosphate is preferentially formed on chemically active sites on the surface of the magnesium alloy. That is, the aluminum or zinc alloy of the alloy component is preferentially formed at a site of high concentration segregation or at a site where an oxide film is not thick. As for the aforementioned discotic acid compound contained in an aqueous solution containing another discotic acid compound, It should be at least one selected from the group consisting of orthophosphoric acid, phosphonic acid, pyroscale acid, trimellitic acid, and metal test salts thereof. As for the concentration conditions of the aqueous solution containing the aforementioned phosphoric acid-based compound, The type of the phosphoric acid-based compound is determined, but the concentration of the phosphoric acid-based compound is preferably 1 to 200 g / L. If the concentration of the phosphoric acid-based compound is less than lg / L, it is difficult to obtain a specified amount of phosphorus attachment, if the concentration exceeds 2 〇g / L, the film will become thicker. (Please read the precautions on the back before filling in this page) # Order ---------- Line I · ------- --- 15 This paper size applies to Chinese National Standard (CNS) A 4 Specifications ⑵G X 297 Gong Chu 544474 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7. V. Description of the invention () The film is thickened. The oil heart is constantly guarded, forming too many rice engravings, and the domain becomes insufficient. Failed to test: Health, or (_: to obtain a good resistance to recording and coating film adhesion, the amount of filling and adhesion, failed, the formation of phosphoric acid recorded on the surface of the town alloy :: the film in the chemical step It also bears the role of dissolving and removing the release agent and oxidation = 'simultaneous silver engraving on the surface. Therefore, the engraving force of the segregation layer of the alloy composition with strong experimental strength is weak, and it cannot be fully dissolved and removed. Qian Zhibian * Detachable clams, oxide layers and alloy componentsΐ layers have a detrimental effect on secretion resistance and coating film adhesion. It is preferably an aqueous solution… pieces, which are in the range of 1 ~ 7 compared to ~ human 丄 x. . IK, etc. can be added to the heart-qi test to add acid components such as tartaric acid and oxalic acid to the acid side. The righteous deeds of the rats ^ 3 know that the contact with the object to be treated in an aqueous solution of a Western-style compound is based on the temperature and time of the aqueous solution containing a phosphoric acid-based compound: member, 'spread, pH, object to be treated The type of the magnesium alloy varies, but it is not necessary, and it can be adjusted appropriately to the aforementioned phosphorus adhesion amount. [Metal surface chemical treatment steps] This paper size is applicable to Chinese National Standard (CNS) A4 specification ⑵Ο X 297 公 爱) --- (Please read the precautions on the back before filling this page)

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544474 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. The description of the invention () The acidic aqueous solution of pH 2 ~ 6 of at least one metal oxyacid compound selected by the group. The chemical treatment solution for each metal surface is in the range of 20 to 1000 mg / L, more preferably in the range of 50 to 500 mg / L, based on the concentration of the fluorine compound. On the other hand, as for the concentration of the metal oxyacid compound, it is preferably in the range of 5 to 10 g / L, and more preferably in the range of 1 to 7 g / L. As for the adhesion weight of the metal surface chemical treatment film when the metal surface chemical treatment liquid has been subjected to the chemical treatment of the metal surface with each of the metal surface chemical treatment liquids, it also varies depending on the type of the ions, but the adhesion weight of the metal ions is preferably 10 to The range of 300 mg / m2 is more preferably in the range of 30 to 200 mg / m2. The humidity of the metal surface chemical treatment liquid at the metal surface chemical treatment step, and the contact time between the magnesium alloy and the object to be treated are based on the composition concentration of the metal surface chemical treatment solution, the surface state of the magnesium alloy, and the target The adhesion weight of the metal surface chemical treatment film can be appropriately set. In the chemical etching step, the magnesium phosphate film formed on the surface of the magnesium alloy has a low chemical activity, and the metal surface is chemically treated on each of the films. The metal surface chemical treatment film system obtained in the step is hardly formed. The aforementioned metal surface chemically-treated film is formed to be a portion where the coating of magnesium phosphate is not covered, or a portion which is not sufficiently covered. As mentioned above, since the magnesium phosphate film formed in the chemical etching step has a low chemical activity, the film itself also functions as a metal surface chemically-treated film that is responsible for improving corrosion resistance and coating film adhesion. Therefore, in the chemical name engraving step, for the parts that are not sufficiently covered with the coating of magnesium phosphate, then by 18 ^ Please read the phonetic on the back? Please fill in this page again for the matters} 0 · άιφ ----------------------- This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297) 544474 A7 B7 V. Description of the invention (Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, followed by the metal surface chemical treatment step for chemical treatment of the metal surface, on the surface of the chemically non-uniform magnesium alloy, it can form a dense and Uniform metal surface chemically treated coating (that is, composite coating), which can impart superior corrosion resistance and coating film adhesion. Inflammation [Each washing step] In the above steps, in order to prevent the treatment solution (degreasing solution) from the previous step, , Acid aqueous solution, decontamination solution, aqueous solution containing phosphoric acid-based compounds, or metal surface chemical treatment liquid) to bring out the improperness caused by the next step (deterioration of the treatment liquid caused by the mixing of various treatment liquids, etc.) to set The water washing step is preferred. The water washing in this water washing step is performed by contacting the magnesium alloy of the object to be treated with water. The degree of mouth washing (contact time, water purity, temperature, water washing stage, dilution) (Magnification, etc.), is not particularly limited, if you consider the concentration of each treatment liquid, the degree of influence when mixing in the next step, etc., you can set it appropriately. 1 [Purified water washing step] Magnesium alloy that has been chemically treated on the metal surface. The surface treatment using the present invention has ended, but the metal surface chemical treatment solution (2 diluted by the water washing step) remaining on the surface is concentrated on drying, the surface of the magnesium alloy or the The film may be corroded. On the surface where a small amount of impurities have remained, coating may be applied to form a coating such as a protruded H pinhole on the coating surface Φ * I. Furthermore, coating may be performed by dip coating. In some cases, impurities may be mixed into the coating for coating, which may degrade the coating. (Please read the precautions on the back before filling this page)-I '

-n Ha aiHi 1 n I line 丨 · ----------------------- 544474 Consumer cooperation of Intellectual Property Bureau of the Ministry of Economic Affairs · A7 ) Therefore, the metal surface remaining on the surface is chemically free of impurities or pure water with less impurities. 2: Washing is better. 'Order pure water. As for the pure water used for the pure water washing step, if it is not deionized to the extent that the coating and other sectors are used as pure water' and [drying step] go through each step shown above ( Part of it is necessary (if necessary) to combine magnesium to evaporate and dry the residual water on the surface. When coating is applied, even if there is residual water on the surface, coating 1 = can =, so no drying is required. However, the moisture is mixed in the paint, the influence of the wave, so it is better to set the drying step at this time. ， 土 "The dry-can system is not particularly limited. For example, although it is also possible to use natural-air drying or hot-air heater drying oven. As mentioned above, according to the surface treatment method of the magnesium alloy of the present invention The magnesium alloy member of the present invention can be obtained by treatment. The magnesium alloy member of the present invention has excellent resistance to I insects even when the state is maintained, but in order to seek further resistance: = to seek the magnesium alloy member The improvement of aesthetics can be advanced if necessary = coating for coating, which is not particularly limited, but the water system, the second one: only one. There are no special restrictions on the coating method; coating, electronic coating Any conventionally known coating method can be used: I Paper size applies Chinese National Standard (CNS) A4 size ⑵G χ 297 publicly issued "(Please read the precautions on the back before filling out this page} .--- *- --------------------------- 544474 A7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs V. Invention Description ([Example] The following is about The surface treatment method of the present invention includes several examples. ^ Yes &gt; Wen Tianran The present invention is not shown by the

Defined by the embodiment. In addition, the fine adjustment of the pH of each treatment liquid in the chemical etching step can be performed by adding sodium hydroxide to the test side itf and appropriately adding phosphoric acid to the acid side (except for Comparative Example 6). ) [Test Materials] The three magnesium alloy plates shown below were used as test materials. • AZ91D (ASTM standard, die-casting method, 100mmx100mmxlmm) AM60B (ASTM standard, die-casting method, i00mmxi〇〇_ xlmm) • AZ31C (ASTM standard, die-casting method, 100__ xl〇〇_xlmm) [Measurement of film adhesion amount] 1. The film adhesion of the film of magnesium phosphonate that has been formed in the step of chemical etching is based on the measurement of the disk adhesion amount in the film. Got. Specifically, the measurement was performed using a commercially available fluorescent X-ray analyzer. That is, many samples with known amounts of phosphorous adhesion and different adhesion amounts are measured, and a strength-adhesion correction curve is prepared in advance using the strength (CPS) at this time. Therefore, the sample to be measured was measured under the same conditions. The strength was measured from this, and the amount of adhesion was converted based on the correction curve. In addition, the sample to be measured is in each of the following Examples or Comparative Examples. After the treatment by the chemical etching step is performed, the sample is washed with water without being subjected to a chemical treatment on the surface of the metal, dried, and cut out to be used for measurement. 2 · Metal surface chemical treatment coating X 297mm) (Please read the precautions on the back before filling this page) -------- ΜΙ0 -------------- I- -------- 544474 A7 V. Description of the Invention (Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs as described above, the two types of fierce and misaligned are used as metal surface chemical treatment fluid. The amount of manganese or thorium attached to the film was measured and obtained. Specifically, the same method as that of the above-mentioned measurement was used in a fluorescent and radiological analyzer of f, based on a correction curve prepared in advance from the measured intensity. Conversion into the amount of adhesion. The sample to be measured is based on each of the following examples or comparative examples. After the metal surface chemical treatment using the metal surface chemical treatment step is applied, it is washed with water, dried, and cut out for measurement. However, as for the amount of bell adhesion, because the test material also contains thorium, the measured value after the chemical treatment on the metal surface is subtracted from the measured value before the chemical treatment on the metal surface (the measured value before the chemical treatment on the metal surface, With the determination of the aforementioned amount of gamma Example 1) AZ91D was used as the test material, and the following treatment steps, the composition of each treatment solution and the treatment conditions were used for surface treatment. [Processing step] Degreasing (alkali degreasing)-water washing-chemical etching- Water washing—chemical treatment of metal surface—water washing—pure water washing—drying [composition and processing conditions of the treatment liquid in each step]. Degreasing step (inspection and degreasing Finecle (registered trademark) MG1101 (manufactured by Parkerizing Co., Ltd.), 3 〇g / L, 6 (rc, 5 minutes, impregnation treatment. '' • Chemical etching step · Orthophosphoric acid, 30 g / L (adjusted to pH 2 5), 25. 〇, 2 knife clock '&gt; Crush treatment 'Dish attachment amount: 〇〇jng / in2 〇 • Chemical treatment step: Magbond (registered trademark) p2〇

(Please read the notes on the back before filling out this page) #i «ΊΘΙ 、 祖 — — — — — — — — 1 — — — — — — — — — — — — Α7

544474 V. Description of Invention ()

(Manufactured by Parkerizing Co., Ltd.), 2000 g / L, 43 ° C, 3 minutes, immersion treatment, manganese adhesion amount: 75 mg / m2. • Water washing between steps: tap water, 25t, 30 seconds, immersion treatment. • Pure water washing. Deionized water (conductivity 2 // S), fully sprayed. • Dry flash · 120 C, 10 minutes drying in hot air oven. Example 2 &lt; &quot; The surface treatment was performed in the same manner as in Example χ except that the composition and processing conditions of the treatment solution in the chemical etching step of Example 1 were changed to those shown below. . Chemical etching step: sodium orthophosphate, 30 g / L (adjusted to ρΗ9.5), 60 ° C, 5 minutes, immersion treatment, phosphorus adhesion amount: 130 mg / m2. Example 3 ^ The surface treatment was performed in the same manner as in Example 1 except that the composition and processing conditions of the treatment solution in the chemical etching step of Example 1 were changed to those shown below. • Chemical etching step: Orthophosphoric acid, 30g / L (adjusted to pH 2 · 5), 25 it, 6 minutes, immersion treatment, phosphorus adhesion amount: 500mg / m2. Example 4 The surface treatment was performed in the same manner as in Example 1, except that the composition and processing conditions of the treatment liquid in the chemical remaining step of Example 1 were changed to those shown below. • Chemical etching step: orthophosphoric acid, 100 g / L (adjusted to ρΗ2.5), 25 ° C, 6 minutes, immersion treatment, phosphorus adhesion amount: 150 mg / m2. Example 5 t The surface treatment was performed in the same manner as in Example 1 except that the composition of the treatment solution and the treatment conditions in the chemical etching step of Example 1 were described below. • Chemical etching step: Orthophosphoric acid, 30g / L (adjusted to P2 · 5), 25π, 15 (Please read the notes on the back before filling out this page) Printed by the Intellectual Property Bureau Staff Consumer Cooperatives of the Ministry of Economic Affairs 23} Paper size applies Zhongguanjia Standard (CNS) A4 specification ⑵G χ 297 public love) -------) ° Jι ~ ϋ 1 n II l I n ϋ ϋ ϋ III i III n ϋ II nn ϋ nn ϋ 544474 A7 B7 Economy The paper size printed by the Ministry of Intellectual Property Bureau's Consumer Cooperatives applies the Chinese national standard (ί%) Α4 specifications (2; ^ V. Description of the invention (seconds, immersion treatment, phosphorus adhesion: 12mg / m2.) Example 6 Except that the composition and processing conditions of the chemical etching step in Example 1 were changed to those shown below, the surface treatment was performed in the same manner as in Example 1. • Chemical etching step: Magbond (registered trademark) M30 (hammer system, said (Manufactured by Yang Parkedizing Co., Ltd.), 50 g / L, 60 ° C, '1 minute, impregnation treatment', wrong adhesion amount: 50 mg / m2. Example 7 Except Bega Example 1, the test material was changed to AM60B, The amount of phosphorus attached to the chemical name engraving step was adjusted to 180mg / m2, and the metal surface was chemically treated. The manganese adhesion amount was adjusted to 70 mg / m2, and the surface treatment was performed in the same manner as in Example i. Example 8 Except that the test material of Example 1 was changed to AZ31C, the phosphorus adhesion amount in the chemical etching step was adjusted to 110 mg / m2. m2, except that the amount of manganese attached to the metal surface chemical treatment step was adjusted to 30 rag / m2, and the surface treatment was performed in the same way as in the example. Also in Comparative Example 1, except that the chemical etch in the treatment step of Example 1 was omitted and The surface treatment was carried out in the same manner as in Example 1. Excess Comparative Example 2 The surface treatment was performed in the same manner as in Example 7 except that the chemistry in the treatment step of Example 7 was omitted. Except for Comparative Example 3, 297 mm) (please first Read the notes on the back and fill out this page) # ------- — Order ----------- Line ------------------ ------ 544474 A7 B7 V. Description of the invention (in the same way as in Example 8): except for the chemical _ step 'Extra Comparative Example 4 The same as in Example 6 except that the processing steps of Example 6 are omitted The surface treatment was carried out using the method of "Knowing Outside". Comparative Example 5 Changed: ΐΐ :! of: The composition of the treatment solution and the processing conditions of the etching step 2 The surface treatment was performed in the same manner as in Example 1. J acid '3Gg / L (adjustment &amp; H2.5), 25 ° C, 10 cores> shellfish treatment, phosphorus adhesion amount · 5mg / m2. Comparative Example 6 Elimination of chemical residues from Shellfish Example 1 Composition and processing conditions of the treatment step of the engraving step = the engraving step (acidic aqueous solution) of the engraving step, and the rest was subjected to surface treatment in the same manner as in Example 1. Famous insect engraving step (acidic aqueous solution): sulfuric acid, 20 g / L (adjusted with sodium hydroxide = ρΗ2 · 5) '25 ° C, 30 seconds, immersion treatment (of course, phosphorus adhesion amount: 0 mg / m2). [Evaluation test] The surface-treated town-gull gold members of each of the examples and comparative examples obtained by the methods described above were subjected to the evaluation tests shown below. The results are summarized and shown in Table 1 below. Test, 0 or more is judged to be a practically acceptable level. 1 · Corrosion resistance after surface treatment For each surface-treated magnesium alloy member (sample) to maintain the original state

The paper size &quot; iS_ S ^ 7 ^ NS) A4 Secret (2i〇7i ^ F 544474 A7 B7 V. Description of the invention (The status printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs is subjected to a pure resistance assessment test. _ Subject to the salt spray test method. Salt 2nd day: Applicable hours. Visually evaluate the health status after 72 hours of salt spray and the purity resistance after surface treatment. Evaluation criteria ^ 1 : Corrosion area ratio is less than 1%. ', Below what. Corrosion area ratio is more than 1% to less than 3%. Corrosion area ratio is more than 3% to less than 5%. Corrosion area ratio is more than 5%. 2. After coating For the surface-treated magnesium alloy components, Ion coating (Kansai Paint Co., Ltd. f, such as 2000) 2G ~ 25_, at 18Gt, 2q minutes, after the resistance test The material is expected to be tested, suitable for JIS-Z2371 based on saltwater Confucianism. Test # ± is to cut the coating film into a checkerboard pattern. The saltwater spraying time is 72 hours. The swelling width was measured on one side of the checkerboard grid, and the corrosion resistance after coating was evaluated. The evaluation criteria are as follows ◎: The swelling width from one side of the checkerboard grid is less than 1 _ .. The swelling width from one side of the checkerboard grid is less than 1mm to 3mm. △: The swelling width from one side of the checkerboard grid is not full. 3mnl or more to less than 5ππη 〇X ·· The swelling width from one side of the checkerboard lattice is less than 5 or more. 3. Coating film adhesion

◎ 〇Δ X f Please read the notes on the back before filling in this page} Μ 26 This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 』Lion, ημ I iM · fama · sbik a · ··· al I ϋ n ϋ n I ϋ I ϋ * ^ in ϋ n · 11 ln 544474 A7 --------- -___ B7_ V. Description of the invention () For each surface-treated magnesium alloy member, The 4 ′ coating film adhesion test using the same coating as the above-mentioned "2. Post-coating property" as the coating film adhesion evaluation test was performed with the chessboard tape method coating film JJIS-K5400, i. . Each) 'is evaluated from the number of remaining coatings. x After the evaluation, the initial water resistance test (4 (rc, 10,000 hours)) was applied. The evaluation criteria are as follows. Order: :: No peeling of the coating film (the number of remaining coating films is 100/100) 〇: The number of remaining coatings is 98/100 or more and less than 100/100 △ • The number of remaining coatings is 95/100 or more and less than 98 / ι〇〇X ·· The number of remaining coatings is less than 95/100 (Please read first Note on the back, please fill in this page) Μ Printed by the Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs

Order: ___ ^ ----- I ------------------------ 544474 A7 B7 V. Description of the invention (Table 1. Evaluation results for test materials Phosphorus adhesion amount (mg / m2) Metal surface chemical treatment Money-resistant coating film Adhesive metal surface chemical treatment After coating, initial water resistance Example 1 AZ91D 200 Manganese-based ◎ ◎ ◎ ◎ Example 2 AZ91D 130 Manganese-based ◎ ◎ ◎ ◎ Example 3 AZ91D 500 孟 Meng ◎ ◎ ◎ ◎ stone example 4 AZ91D 1500 violent ◎ ◎ ◎ ◎ Example 5 AZ91D 12 violent 〇 ◎ ◎ Example 6 AZ91D 200 鍅 ◎ ◎ ◎ ◎ Example 7 AM60B 180 Tortoise ◎ ◎ ◎ ◎ Example 8 AZ31C 110 Fierce Series ○ ◎ ◎ Comparative Example 1 AZ91D 0 Slit * 糸 X △ 〇 Comparative Example 2 AM60B 0 in Mengyang ΔX ◎ ○ Comparative Example 3 AZ31C 0 in Mengyang XX ◎ Δ Comparative Example 4 AZ91D 0 Zinc Δ Δ ◎ 〇 Comparative Example 5 AZ91D 5 Slit Δ Δ ◎ ◎ Comparative Example 6 AZ91D 0 Slit Δ Δ ◎ ◎ From Table 1 above, it can be seen that the treatment using the chemical etching step, If the surface of the town alloy member is cleaned and a film of magnesium phosphate is formed, Example 1 ~ 8, compared with Comparative Example 丄 ~ 4 in which the chemical etching step has been omitted, it can be seen that the female is resistant to scorching and the coating is strong. Also in Comparative Example 5, if the amount of film attachment of the dish acid money is less than the specified amount, it is not Can get enough performance 'Comparative Example 6 which used sulfuric acid for the chemical etching step, but also failed to obtain good performance. This paper size applies Chinese National Standard (CNS) A4 specifications ^ 7 ^ 77 ^ 7 (Please read the back first (Please note this page before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs

Order L --------- line-r ---------------- II 544474

[Effects of the invention] As described above, by using the surface treatment method of the present invention to surface-treat the annealed metal, a surface having excellent corrosion resistance and coating film adhesion can be formed. In the surface treatment method of the present invention, chemically uneven surfaces can also cause formation of sensitive and uniform leaks. Therefore, the shape of the product or the part of the product is difficult to be affected by constraints, and can be used safely. performance. The chemical engraving solution used in this description does not contain hexavalent chromium that is harmful to the human environment. Therefore, if the so-called chromate agent is not used as the surface chemical treatment agent of i, it is m. People with value. (Please read the notes on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs

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Claims (1)

5444 (74 α Α8 Β8 C8 D8 The Ministry of Economic Affairs and the Intellectual Property Office of the People ’s Republic of China are responsible for the printing of patents and scope of patents. A surface treatment method for magnesium alloys, which is characterized by a step of degreasing the grease on the surface of the magnesium alloys and performing chemical etching. A chemical silver engraving step for processing and a surface treatment method for forming a metal surface chemical treatment step by using a metal surface chemical treatment solution. The aforementioned chemical name engraving step is to contact the surface of the aforementioned magnesium alloy with an aqueous solution containing a phosphoric acid-based compound to attach to the cattle. The step of forming a film of magnesium phosphate of 10 to 2000 mg / m2 is set. 2 · = Surface treatment method of magnesium alloy according to item 丨 of the patent application, in which the chemical etching step contains an aqueous solution of a phosphoric acid-based compound containing an acid-based compound, such as n-linic acid, phosphonic acid, pyromellitic acid, trimer At least one selected from the group consisting of dishic acid and such alkali metal salts. The concentration of the phosphoric acid-based compound is in the range of 1 to 200 g / L, and the pH is in the range. 3. The surface treatment method for alloys according to item 15 or item 2 of the application patent range 15, wherein the aforementioned metal surface chemical treatment solution contains at least orthophosphoric acid and at least one metal selected from the group consisting of Zη, Mn and Ca Acidic aqueous solution with pH of 2 ~ 6. 4 · If you apply for the surface treatment method of magnesium alloy in item} or item 2 of the third method, wherein the aforementioned metal surface chemical treatment solution contains hydrofluoric acid, silicohydrofluoric acid, zirconium hydrofluoric acid, and titanium hydrofluoric acid At least one fluorine compound selected from the resulting group, and an acidic aqueous solution of pH 2 to 6 of at least one metal oxyacid compound selected from the group consisting of Mn, Mo, Ta, Re, Nb, and V. --------------- IT —----- ^ (Please read the precautions on the back before filling out this page) 5 statuses Shicai Guanjia County 544474 A8 B8 C8 D8 VI. Application scope of patent t 5 · —A kind of magnesium alloy component, which is characterized by surface treatment using the surface treatment method of the magnesium alloy according to any one of the scope of the application for items 1 to 4. (Please read the precautions on the back before filling out this page) Order Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper size applies to Chinese national standards (CNS &gt; A4 size (210X 297 mm)