Aluminum material or aluminum alloy material with a coating, method for manufacturing the same, and water-based surface treatment agent

Abstract

To provide an aluminum material or an aluminum alloy material with a surface treatment coating film that has excellent thermal and corrosion resistance.SOLUTION: The problem is solved by an aluminum material or an aluminum alloy material which has a coating film that contains chromium, zirconium, zinc and carbon in the surface or on the surface of the aluminum material or the aluminum alloy material, where the infrared spectrum of the coating film as determined by the specular reflection method of Fourier transform infrared spectroscopy (FT-IR) has peaks in the range of 3,600 cm-1 to 3,000 cm-1 and in the range of 1,750 cm-1 to 1,700 cm-1.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an aluminum material or aluminum alloy material having a surface treatment film with excellent heat resistance and corrosion resistance, and to a method for producing the same. It also relates to a water-based surface treatment agent capable of forming a surface treatment film with excellent heat resistance and corrosion resistance on or onto the surface of an aluminum material or aluminum alloy material. [Background technology]

[0002] In a wide range of fields, including aircraft materials, building materials, and automotive parts, aluminum or aluminum alloy materials with a surface treatment coating, which is applied using a surface treatment agent containing chromium ions, have been used to impart corrosion resistance.

[0003] For example, Patent Document 1 discloses a chemical conversion treatment solution for metal materials that contains a component (A) consisting of a water-soluble trivalent chromium compound, a component (B) consisting of at least one selected from a water-soluble titanium compound and a water-soluble zirconium compound, a component (C) consisting of a water-soluble nitrate compound, a component (D) consisting of a water-soluble aluminum compound, and a component (E) consisting of a fluorine compound, and whose pH is controlled to be in the range of 2.3 to 5.0.

[0004] Patent Document 2 discloses a chemical treatment solution containing predetermined amounts of a specific trivalent chromium compound, a specific zirconium compound, and a specific dicarboxylic acid compound.

[0005] Furthermore, Patent Document 3 discloses a surface treatment agent for aluminum or aluminum alloys containing a trivalent chromium ion (A), at least one ion selected from titanium-containing ions and zirconium-containing ions (B), a zinc-containing ion (C), a free fluoride ion (D), and a nitrate ion (E). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-328501 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-316334 [Patent Document 3] Japanese Patent No. 6910543 [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] Aluminum materials or aluminum alloy materials may be exposed to high-temperature environments depending on their applications. However, the films formed on aluminum materials or aluminum alloy materials using the surface treatment agents according to Patent Documents 1 and 2 have room for improvement in terms of the decrease in corrosion resistance (heat-resistant corrosion resistance) when exposed to high-temperature environments. Also, even when the surface treatment agent according to Patent Document 3 is used, although the heat-resistant corrosion resistance has been improved, it still cannot be said to be sufficient.

[0008] An object of the present invention is to provide an aluminum material or an aluminum alloy material provided with a surface treatment film having excellent heat-resistant corrosion resistance. Another object is to provide a surface treatment agent capable of forming such a surface treatment film. [Means for Solving the Problems]

[0009] As a result of intensive studies to solve the above problems, the present inventors have found that an aluminum material or an aluminum alloy material provided with a film containing chromium, zirconium, zinc, and carbon on the surface or on the surface thereof and having a characteristic infrared reflection peak has excellent corrosion resistance and excellent heat-resistant corrosion resistance, and thus completed the present invention. That is, the present invention provides:

[0010] (1) An aluminum material or an aluminum alloy material provided with a film containing chromium, zirconium, zinc, and carbon on the surface or on the surface thereof, ​In the infrared spectrum of the film measured by the specular reflection method of Fourier transform infrared spectroscopy (FT-IR), peaks appear at 3600 cm -1 ~3000 cm -1 and 1750 cm -1 ~1700 cm -1 and, an aluminum material or an aluminum alloy material; (2) The film has a chromium content within the range of 5 mg / m 2 ~100 mg / m 2 and a zirconium content within the range of 2 mg / m 2 ~150 mg / m 2 and a carbon content within the range of 2 mg / m 2 ~20 mg / m 2 and, with the total content of chromium, zirconium, and zinc measured by X-ray photoelectron spectroscopy (XPS) being 100 atomic%, the zinc content is 2 atomic% to 60 atomic%, the aluminum material or aluminum alloy material according to (1); (3) An aqueous surface treatment agent used for surface treatment of an aluminum or aluminum alloy material, the aqueous surface treatment agent containing an ion (A) containing chromium, an ion (B) containing zirconium, an ion (C) containing zinc, and an organic compound (D) having a hydroxyl group and a carboxyl group; (4) A contact step of bringing the surface treatment agent according to (3) into contact with the surface or on the surface of an aluminum material or an aluminum alloy material, a manufacturing method of an aluminum material or an aluminum alloy material provided with a film including the contact step; etc. are included.

Advantages of the Invention

[0011] According to the present invention, an aluminum material or an aluminum alloy material provided with a surface treatment film having excellent heat and corrosion resistance can be provided. Further, a surface treatment agent capable of forming the surface treatment film can be provided.

Embodiments for Carrying Out the Invention

[0012] The following describes, in the order described below, an aluminum material or aluminum alloy material equipped with a surface treatment coating according to this embodiment, a surface treatment agent capable of forming the surface treatment coating, and a method for manufacturing them. (1) Aluminum material or aluminum alloy material (2) Surface treatment coating (3) Surface treatment agents (4) Manufacturing method

[0013] (1) Aluminum material or aluminum alloy material The aluminum material or aluminum alloy material is not particularly limited as long as it is a metallic material containing aluminum. In particular, aluminum die-cast material, which has a thick oxide film on its surface and segregated alloy components, making it difficult to impart corrosion resistance, is effective as a material for forming the surface treatment film in this embodiment. The applications of the aluminum material or aluminum alloy material with the surface treatment film are not particularly limited, but it is preferable to use it as a part that is exposed to high-temperature environments depending on the usage conditions, such as engine parts and ECU housings, because the heat resistance and corrosion resistance do not deteriorate easily. The aluminum material or aluminum alloy material with the surface treatment film can have a longer lifespan due to improved heat resistance and corrosion resistance, thereby enabling the effective use of resources.

[0014] (2) Surface treatment coating The surface treatment coating according to this embodiment is applied to the surface or surface of an aluminum material or aluminum alloy material. It is formed on a surface and contains chromium, zirconium, zinc, and carbon. It may be formed from these elements alone, or it may contain other components. The composition (content) of each coating component is described in detail below.

[0015] (2-1) Chromium The form of chromium contained in the surface treatment film is not particularly limited; it may be metallic chromium, chromium oxides such as hexavalent chromium oxide or trivalent chromium oxide, or chromium compounds bonded with components contained in the surface treatment agent. It may contain one of these forms, or two or more. The chromium content in the surface treatment film is typically 5 mg / m² in terms of metallic chromium. 2 ~100mg / m 2 It is within the range, preferably 10 mg / m² 2 ~50mg / m 2 It is within the range, and more preferably 10 mg / m² 2 ~30mg / m 2 It is within the specified range. The chromium content in the surface treatment film is measured using an X-ray fluorescence analyzer.

[0016] (2-2) Zirconium The form of zirconium contained in the surface treatment film is not particularly limited; it may be metallic zirconium, zirconium oxide, or a zirconium compound bonded with components contained in the surface treatment agent. It may contain one of these forms, or two or more. The zirconium content in the surface treatment film is typically 2 mg / m² in terms of metallic zirconium. 2 ~150mg / m 2 It is within the range, preferably 5 mg / m² 2 ~100mg / m 2 It is within the range, and more preferably 5 mg / m² 2 ~50mg / m 2 It is within the specified range. The zirconium content in the surface treatment film is measured using an X-ray fluorescence analyzer.

[0017] (2-3) Zinc The form of zinc contained in the surface treatment film is not particularly limited; it may be metallic zinc, zinc oxide, or a zinc compound bonded with a component contained in the surface treatment agent. It may contain one of these, or two or more.

[0018] (2-4) Ratio of zinc content to the total content of chromium, zirconium, and zinc With the total content of chromium, zirconium, and zinc contained in the surface treatment film being 100 atomic%, the proportion of zinc content (Zn / (Cr+Zr+Zn)) is usually preferably in the range of 2 atomic% to 60 atomic%, more preferably in the range of 10 atomic% to 40 atomic%, and even more preferably in the range of 10 atomic% to 30 atomic%. To determine the ratio of zinc content to the total content of chromium, zirconium, and zinc (Zn / (Cr+Zr+Zn)), the content of each component in the surface treatment film is measured by repeatedly performing sputtering and elemental measurement by X-ray photoelectron spectroscopy (XPS) using an X-ray photoelectron spectrometer. The depth position in XPS is controlled by the distance at which SiO2 is sputtered by Ar ions. Specifically, sputtering is performed for 0.25 minutes (sputtering rate: 11.0 nm / min in SiO2 equivalent), and monochromatic Al Kα rays are analyzed at an analysis diameter of 100. The sample surface is irradiated with a micrometer beam, and the resulting photoelectrons are measured. This process is repeated, and the content of chromium, zirconium, and zinc obtained at each depth in the thickness direction of the surface treatment film is measured. The sum of these is taken as 100 atomic percent, and the percentage of zinc content (Zn / (Cr+Zr+Zn)) is calculated.

[0019] (2-5) Carbon All or part of the carbon contained in the surface treatment film originates from organic compounds having hydroxyl and carboxyl groups that are blended into the surface treatment agent. The carbon content in the surface treatment film is typically 2 mg / m². 2 ~20mg / m 2 It is within the range, preferably 3 mg / m² 2 ~15mg / m 2 It is within the range, and more preferably 4 mg / m² 2 ~12mg / m 2 Within the range The carbon content in the surface treatment film is measured using a total organic carbon meter.

[0020] (2-6) Peaks in the infrared spectrum The infrared spectrum of the surface-treated film can be obtained by measuring it using the specular reflection method of Fourier transform infrared spectroscopy (FT-IR). The infrared spectrum obtained by measuring the surface-treated film in this embodiment has peaks within a specific wavelength range. A peak originating from hydroxyl groups is located at 3600 cm⁻¹. -1 ~3000cm -1 It appears at 1750 cm, with a peak originating from the carboxyl group. -1 ~1700cm -1 It appears there. The infrared spectrum was measured using a Fourier transform infrared spectrophotometer at wavenumber = 4000 cm⁻¹. -1 ~400cm -1 , resolution=4cm -1 This is obtained by measuring under the condition of 128 scans. Aluminum or aluminum alloy material without surface treatment coatings is used as the background. As described above, an aluminum material or aluminum alloy material equipped with a surface treatment film according to this embodiment can be described in particular by ensuring that the zinc content in the surface treatment film is within the above range and that the infrared spectrum measured of the surface treatment film has a peak within the above wavelength range.

[0021] (3) Surface treatment agents The surface treatment agent according to this embodiment is a surface treatment agent used for surface treatment of aluminum or aluminum alloy materials. This surface treatment agent can be used as a chemical conversion agent. The surface treatment agent contains chromium-containing ions (A), zirconium-containing ions (B), zinc-containing ions (C), and an organic compound (D) having hydroxyl and carboxyl groups. The surface treatment agent may be prepared by blending only the sources of these ions (A) to (C) and the organic compound (D) in an aqueous medium, or it may be prepared by blending these with other components. The components, composition (content), and properties of each component are described in detail below.

[0022] (3-1) Aqueous medium The aqueous medium is not particularly limited as long as it is water or a mixture of water and a water-miscible organic solvent (containing 50% or more water by volume based on the volume of the aqueous medium). The water-miscible organic solvent is not particularly limited as long as it is miscible with water, and examples include ketone solvents such as acetone and methyl ethyl ketone; amide solvents such as N,N'-dimethylformamide and dimethylacetamide; alcohol solvents such as methanol, ethanol, and isopropanol; ether solvents such as ethylene glycol monobutyl ether and ethylene glycol monohexyl ether; and pyrrolidone solvents such as 1-methyl-2-pyrrolidone and 1-ethyl-2-pyrrolidone. One of these water-miscible organic solvents may be mixed with water, or two or more may be mixed with water.

[0023] (3-2) Ions containing chromium (A) The source of chromium-containing ions (A) in the surface treatment agent is not particularly limited, as long as ions (A) can be provided by mixing them with an aqueous medium. Examples include chromium fluoride, chromium nitrate, chromium sulfate, and chromium phosphate. Only one of these may be used, or two or more may be used. The content of ions (A) in the surface treatment agent is not particularly limited, but is usually in the range of 5 to 1000 mg / L in terms of chromium-equivalent mass concentration, preferably in the range of 50 to 500 mg / L, and more preferably in the range of 100 to 200 mg / L. Ions (A) may also contain trivalent chromium.

[0024] (3-3) Ions containing zirconium (B) The source of zirconium-containing ions (B) in the surface treatment agent is not particularly limited, as long as it can provide ions (B) by mixing with an aqueous medium. For example, Examples include zirconium sulfate, zirconium oxysulfate, zirconium ammonium sulfate, zirconium nitrate, zirconium oxynitrate, zirconium ammonium nitrate, hexafluorozirconium acid, hexafluorozirconium complex salt, zirconium acetate, zirconium lactate, zirconium tetraacetylacetonate, zirconium tributoxyacetylacetonate, tetran-n-butoxyzirconium, and tetran-n-propoxydylzirconium. These may be used individually or in combination of two or more. The content of ion (B) in the surface treatment agent is not particularly limited, but is usually in the range of 5 to 1000 mg / L in terms of zirconium-equivalent mass concentration, preferably in the range of 30 to 300 mg / L, and more preferably in the range of 70 to 200 mg / L.

[0025] (3-4) Ions containing zinc (C) The source of zinc-containing ions (C) in the surface treatment agent is not particularly limited, as long as it can provide ions (C) by mixing with an aqueous medium. Examples include metallic zinc, zinc oxide, zinc carbonate, zinc nitrate, zinc chloride, zinc sulfate, zinc fluoride, zinc iodide, zinc dihydrogen phosphate, and zinc acetylacetonate. One of these may be used, or two or more may be used. The content of ions (C) in the surface treatment agent is not particularly limited, but is usually in the range of 500 to 10000 mg / L in terms of zinc equivalent mass concentration, preferably in the range of 1000 to 5000 mg / L, and more preferably in the range of 1500 to 2000 mg / L.

[0026] (3-5) Organic compounds having hydroxyl groups and carboxyl groups (D) The organic compound (D) containing hydroxyl and carboxyl groups is not particularly limited as long as it can be mixed in an aqueous medium. Examples include organic acids such as gluconic acid, heptogluconic acid, galactonic acid, mannonic acid, glucaric acid, galactaric acid, mannaric acid, arabinonic acid, fructuronic acid, glucuronic acid, iduronic acid, galacturonic acid, mannuronic acid, and guluronic acid, and their salts (e.g., sodium salts, potassium salts). Only one of these may be used, or two or more may be used. The amount of organic compound containing hydroxyl and carboxyl groups in the surface treatment agent is not particularly limited, but is usually in the range of 2 to 2000 mg / L, preferably in the range of 10 to 1000 mg / L, and more preferably in the range of 100 to 300 mg / L.

[0027] (3-6) Free fluoride ions (E) The surface treatment agent may contain free fluoride ions (E). The source of free fluoride ions (E) in the surface treatment agent is not particularly limited, as long as it can provide free fluoride ions (E) when mixed with an aqueous medium. Examples include hydrofluoric acid, ammonium fluoride, chromium fluoride, hexafluorotitanium acid, hexafluorotitanium complex salt, hexafluorozirconium acid, hexafluorozirconium complex salt, magnesium fluoride, aluminum fluoride, hexafluorosilicic acid, sodium fluoride, potassium fluoride, zinc fluoride, borofluoric acid, sodium borofluoride, and ammonium borofluoride. Only one of these may be used, or two or more may be used. Furthermore, the free fluoride ions (E) may be provided by the same compound as the source of ions (A), (B), and / or (C) above, or by a different compound. The fluorine-based mass concentration of free fluoride ions (E) in the surface treatment agent is not particularly limited, but is preferably 70 to 200 mg / L, and more preferably 80 to 150 mg / L. In this specification, the free fluoride ion concentration refers to the value at the temperature at which the surface treatment agent is brought into contact with the surface of an aluminum material or aluminum alloy material. The free fluoride ion concentration is measured according to well-known methods, and can be performed, for example, using a commercially available ion meter.

[0028] The surface treatment agent of this embodiment may contain various metal compounds, as long as it does not impair the effects of the present invention. Metal components and additives may be added. Examples of metal components include vanadium, molybdenum, tungsten, manganese, cerium, magnesium, calcium, cobalt, nickel, strontium, lithium, niobium, yttrium, and bismuth. Examples of additives include compounds having a formyl group, a benzoyl group, an amino group, an imino group, a cyano group, an azo group, a thiol group, a sulfo group, a nitro group, an amidino group, a urethane bond, and an aromatic ring. Only one of these metal components or additives may be used, or two or more may be used. Since these metal components and additives are added within a range that does not impair the effects of the present invention, their content is at most about a few mass percent of the total amount of surface treatment agent.

[0029] (3-7) pH of surface treatment agent The pH of the surface treatment agent according to this embodiment is not particularly limited, but is preferably 3.0 to 6.0, and more preferably 4.0 to 5.0. In this specification, pH refers to the value at the temperature at which the surface treatment agent is brought into contact with the surface of an aluminum material or aluminum alloy material. The pH is measured according to a well-known method, and can be measured, for example, using a commercially available pH meter.

[0030] The composition of the surface treatment agent according to this embodiment has been described above. Another aspect of the present invention is a surface treatment agent used for surface treatment of aluminum or aluminum alloy materials, comprising a source of chromium-containing ions (A), a source of zirconium-containing ions (B), a source of zinc-containing ions (C), and an organic compound (D) having hydroxyl and carboxyl groups, blended in an aqueous medium. One or more of the source compounds may be used.

[0031] (4-1) Method for manufacturing surface treatment agent The surface treatment agent according to this embodiment can be obtained by mixing an appropriate amount of a source of chromium-containing ions (A), a source of zirconium-containing ions (B), a source of zinc-containing ions (C), and an organic compound (D) having hydroxyl and carboxyl groups into an aqueous medium and stirring. In the manufacturing process, the solid source may be mixed into the aqueous medium, or the solid source may be dissolved in the aqueous medium beforehand and then mixed as an aqueous medium solution. The pH range of the surface treatment agent is as described above, and it is preferable to adjust the pH using pH adjusting agents such as nitric acid, sulfuric acid, hydrofluoric acid, ammonium bicarbonate, aqueous ammonia, sodium bicarbonate, and sodium hydroxide, but it is not limited to these components. One or more pH adjusting agents may be used.

[0032] (4-2) Method for manufacturing aluminum or aluminum alloy material with a surface treatment coating A method for manufacturing an aluminum or aluminum alloy material equipped with a surface treatment film formed by the surface treatment agent according to this embodiment includes a step of contacting the surface treatment agent according to this embodiment with the surface of the aluminum or aluminum alloy material or onto its surface. This forms a surface treatment film on the surface of the aluminum or aluminum alloy material. A pretreatment step such as a washing step or a pickling step may be performed before the contact step. A water washing step may be performed after each step, or a drying step may be performed after the water washing step.

[0033] (4-3) Aluminum or aluminum alloy material The aluminum or aluminum alloy materials targeted by the surface treatment agent are not particularly limited, but it is especially effective for aluminum die-cast materials with a thick oxide film on the surface and segregated alloy components. The applications of the aluminum or aluminum alloy materials are not particularly limited, but examples include engine peripheral equipment and ECU housings.

[0034] (4-4) Washing process In the manufacturing method of this embodiment, it is preferable to perform a cleaning step in which a known cleaning agent is brought into contact with the surface or surface of an aluminum or aluminum alloy material before performing the contact step. The cleaning method is not particularly limited, but examples include solvent degreasing and alkaline degreasing.

[0035] (4-5) Pickling process In the manufacturing method of this embodiment, a pickling step may be performed before the contact step, in which a known pickling agent is brought into contact with the surface or surface of the aluminum or aluminum alloy material. The pickling agent is not particularly limited, but examples include nitric acid and hydrofluoric acid.

[0036] (4-6) Contact process In the contact step of the manufacturing method of this embodiment, the contact temperature and contact time are not particularly limited, but typically the surface treatment agent is brought into contact with the surface of the aluminum or aluminum alloy material at 30 to 80°C, preferably 40 to 60°C, for 10 to 1200 seconds. After this step, if necessary, the material may be washed with water, deionized with water, and then dried. The drying temperature is not particularly limited, but 15 to 100°C is preferred. The method for bringing the surface treatment agent into contact with the surface of the aluminum or aluminum alloy material is not particularly limited, but examples include immersion, spraying, flow coating, etc.

[0037] (Post-processing steps) The aluminum or aluminum alloy material with a surface treatment coating manufactured by the above manufacturing method may be further post-treated with hot water, rust inhibitors, post-treatment agents, pH adjusters, coupling agents, etc. After the above post-treatment, it may be washed with water and then dried, or dried without washing with water.

[0038] Furthermore, aluminum or aluminum alloy materials with a surface treatment coating have excellent corrosion resistance even without a painting process on top of the surface treatment coating, and also have excellent corrosion resistance (heat corrosion resistance) even when the surface treatment coating is exposed to high temperatures, although a painting process may be performed. The aforementioned coating process is not particularly limited, but can be carried out using known coating compositions by coating methods such as water-based coating, solvent coating, powder coating, anionic electrodeposition coating, or cationic electrodeposition coating. [Examples]

[0039] Examples and comparative examples of the present invention are described below. However, the present invention is not limited to these examples.

[0040] <Aluminum material> Aluminum die-cast material (JIS-ADC12) <Surface treatment agent> Surface treatment agents according to the examples and comparative examples were obtained by adding and mixing each raw material to water to the concentrations shown in Table 1. Ammonia water or nitric acid was used as a pH adjuster. pH and free fluoride ion concentration (represented as FF in Table 1) were measured using a portable ion / pH meter [IM-32P (manufactured by Toa DKK Co., Ltd.), pH electrode: GST-2729C (manufactured by Toa DKK Co., Ltd.), ion electrode: fluoride ion composite electrode F-2021 (manufactured by Toa DKK Co., Ltd.)].

[0041] <Processing method> Specifically, the aluminum die-cast material was immersed in an alkaline degreasing agent [Fine Cleaner 315E (manufactured by Nippon Parkerizing Co., Ltd.) 20g / L aqueous solution] at 50°C for 2 minutes, and then the surface was rinsed with tap water to clean it. After that, the surface treatment agent was immersed on or onto the surface of the aluminum die-cast material at the contact temperature listed in Table 1. The contact process was carried out accordingly. After that, the materials were rinsed with running tap water (at room temperature for 30 seconds), then with running deionized water (at room temperature for 30 seconds), and finally dried with an air blower (at room temperature for 30 seconds) to obtain aluminum die-cast materials (test pieces 1-39) with a surface treatment coating.

[0042] <Measurement of surface treatment coatings> The content of each component in the surface treatment film of an aluminum die-cast material obtained by the above surface treatment method, and the infrared peaks of the surface treatment film were measured by the following method. The measurement results are shown in Table 2.

[0043] <Metal content> The metal content (chromium, zirconium) was measured using an X-ray fluorescence analyzer [ZSX PrimusIV (manufactured by Rigaku Corporation)].

[0044] <Percentage of zinc content relative to the total content of chromium, zirconium, and zinc> To determine the ratio of zinc content to the total content of chromium, zirconium, and zinc (Zn / (Cr+Zr+Zn)), the content of each component in the surface treatment film was measured by repeatedly performing sputtering and elemental measurement by XPS using an X-ray photoelectron spectrometer [PHI5000VersaProbeIII (ULVAC-PHI)]. The depth position in XPS was controlled by the distance at which SiO2 was sputtered by Ar ions. Specifically, sputtering was performed for 0.25 minutes (sputtering rate: 11.0 nm / min in terms of SiO2), and monochromatic Al Kα rays were irradiated onto the sample surface at an analysis diameter of 100 μm. The resulting photoelectrons were measured. This process was repeated, and the content of chromium, zirconium, and zinc obtained at each depth in the thickness direction of the surface treatment film was measured. The sum of these was set to 100 atomic percent, and the percentage of zinc content (Zn / (Cr+Zr+Zn)) was calculated.

[0045] <Carbon Content> The carbon content (total organic carbon deposition) was measured using a total organic carbon meter [TOC-L (manufactured by Shimadzu Corporation)].

[0046] <Infrared Peak> The infrared spectrum of the surface-treated coating was obtained by measuring it using the specular reflection method of Fourier transform infrared spectroscopy (FT-IR). Specifically, the infrared spectrum was measured using a Fourier transform infrared spectrophotometer [ALPHA (manufactured by Bruker)] at wavenumber = 4000 cm⁻¹. -1 ~400cm -1 , resolution=4cm -1 The results were obtained by measuring under the condition of 128 scans. An aluminum die-cast material without a surface treatment coating was used as the background. The obtained infrared spectrum was 3600 cm⁻¹. -1 ~3000cm -1 Within the wavelength range and 1750 cm -1 ~1700cm -1 We checked whether or not there was a peak within the wavelength range.

[0047] <Evaluation of test specimens> Furthermore, the following tests were conducted on the test specimens to evaluate the corrosion resistance and post-heat corrosion resistance (heat corrosion resistance) of the aluminum die-cast material with a surface treatment coating. The results are shown in Table 3.

[0048] ≪Evaluation Method≫ <Corrosion resistance> A neutral salt spray test (JIS-Z2371:2015) was performed on test specimens 1-39 for 360 hours. After drying, the percentage of white rust that formed on the surface of the test specimens was measured visually. The percentage of white rust is the ratio of the area where white rust formed to the area of ​​the observed area. The evaluation criteria are as follows. The evaluation results are shown in Table 3. <Evaluation Criteria> 5. Percentage of white rust: 5% or less 4. Percentage of white rust: Over 5% to 10% or less 3. Percentage of white rust: Over 10% to 30% or less 2. Percentage of white rust: Over 30% to 50% or less 1. Percentage of white rust: over 50%

[0049] <Heat and corrosion resistance> Each test specimen was heated in an electric oven (150°C for 6 hours), followed by a neutral salt spray test (JIS-Z2371:2015) for 240 hours. After drying, the percentage of white rust that formed on the surface of the test specimen was visually measured. This is the ratio of the area where white rust formed to the area of ​​the observed area. The evaluation criteria are as follows. The evaluation results are shown in Table 3. <Evaluation Criteria> 5. Percentage of white rust: 5% or less 4. Percentage of white rust: Over 5% to 10% or less 3. Percentage of white rust: Over 10% to 30% or less 2. Percentage of white rust: Over 30% to 50% or less 1. Percentage of white rust: over 50%

[0050] [Table 1]

[0051] [Table 2]

[0052] [Table 3]

Claims

1. An aluminum material or aluminum alloy material having a coating containing chromium, zirconium, zinc, and carbon on or on the surface of the aluminum material or aluminum alloy material, In the infrared spectrum of the film measured by specular reflection using Fourier transform infrared spectroscopy (FT-IR), the peak was 3600 cm⁻¹. －１ ~3000cm －１ and 1750cm －１ ~1700cm －１ And then it appeared, The aforementioned coating is an aluminum material or aluminum alloy material in which the zinc content is 2 atomic% to 60 atomic%, with the total content of chromium, zirconium, and zinc, as measured by X-ray photoelectron spectroscopy (XPS), being set at 100 atomic%.

2. The film has a chromium content within the range of 5 mg / m ２ to 100 mg / m ２ and a zirconium content within the range of 2 mg / m ２ to 150 mg / m ２ and a carbon content within the range of 2 mg / m ２ to 20 mg / m ２ The aluminum material or aluminum alloy material according to claim 1, wherein the film is within the above ranges.

3. A water-based surface treatment agent used for surface treatment of aluminum or aluminum alloy materials, containing chromium-containing ions (A), zirconium-containing ions (B), zinc-containing ions (C), and an organic compound (D) having hydroxyl and carboxyl groups. The content of the aforementioned ion (A) is 5 to 500 mg / L in terms of chromium-equivalent mass concentration. The content of the aforementioned ion (B) is 5 to 300 mg / L in terms of zirconium-equivalent mass concentration. A water-based surface treatment agent having an ion (C) content of 500 to 10,000 mg / L in terms of zinc-based mass concentration.

4. A method for manufacturing an aluminum material or an aluminum alloy material comprising a coating film, the method comprising a contact step of bringing the surface treatment agent described in claim 3 into contact with the surface of an aluminum material or an aluminum alloy material.

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