Surface of anodized aluminum or aluminum alloy parts versus laser marking methods

Abstract

This invention relates to a method for marking the surface of aluminum or aluminum alloy parts, comprising at least the following steps: A) an anodizing step; B) a sealing step; and D) a marking step using a fiber laser beam. The invention also relates to the use of the marking method according to the invention for manufacturing or marking aluminum or aluminum alloy parts for use in the aerospace, automotive, railway, watchmaking, medical, nuclear, and petroleum industries.

Description

Technical Field

[0001] The present invention relates to the use of contrast laser marking or engraving on aluminum or aluminum alloy parts to improve their resistance to biological corrosion and salt spray environments.

[0002] Contrast laser marking can also be used to generate contrast marks on the surface of aluminum or aluminum alloy parts without removing any material. This facilitates and ensures the visibility and reliable, repeatable reading of, for example, Data Matrix Codes (DMC) or Unique Device Identifier (UDI) codes, regardless of the reading environment (dark or bright) and the reading angle.

[0003] Laser-marked aluminum or aluminum alloy parts are used in aerospace, automotive, railway, watchmaking, medical, nuclear and petroleum industries, etc. Background Technology

[0004] Marking metal parts with text, markings, images, numbers, QR codes, etc., for traceability, anti-counterfeiting, and / or part identification is used in many industries, such as aerospace, automotive, railway, watchmaking, medical, nuclear, and petroleum. For the purposes of this demonstration, the terms "marking" and "engraving" are used interchangeably to refer to the same operation or method. Laser marking is a method that has attracted increasing interest over the past few decades because it offers many advantages: speed, the ability to mark with high precision to achieve consistent quality, and resistance to wear and heat. However, laser marking is a subtractive method based on the use of a laser beam that removes material with each laser pulse. Metal parts marked in this way, especially those made of aluminum or aluminum alloys, are exposed (e.g., white-raw aluminum) and are not resistant to corrosion and biodegradation. Currently, post-marking corrosion protection treatments involve chemical conversion, for example, applying a protective coating with Bonderite MCR 1200 from Henkel or Surtec 650 from Surtec. This means that there are more stages in the manufacturing of components or equipment, the manufacturing cycle time is longer, and the risk of non-conformity increases, because the more stages in the manufacturing cycle, the greater the risk of poor process quality, and so on.

[0005] When engraved / marked in white, the parts cannot resist biodegradation even after post-treatment (such as conversion).

[0006] US2003 / 0201259 describes a method for marking the surface of an aluminum or aluminum alloy component having an anodized layer, the method comprising the step of marking a surface area with a laser beam of wavelength between 700 nm and 1400 nm, particularly between 1000 nm and 1100 nm, and even more particularly 1064 nm. The laser beam penetrates at least a majority of the anodized surface layer and locally causes a visually observable change. Areas of the anodized layer located further away remain unchanged. The protective function of the anodized layer is not compromised, and the exterior of the layer is free of irregularities, just as it was before the marking was applied.

[0007] Another drawback of laser marking on metal parts, particularly aluminum or aluminum alloys, is its visibility and legibility. Currently, the markings have low contrast, making them not very visible / readable, or only readable in specific environments and under specific conditions. Post-marking treatments, such as chemical conversions, can also alter the visibility / legibility of the markings.

[0008] Therefore, there is indeed a need for a laser-based method to mark the surface of aluminum or aluminum alloy parts to improve their biocorrosion and corrosion resistance without requiring post-marking chemical conversion treatment and in compliance with REACH regulations.

[0009] In particular, there is a real need for a method to mark the surface of aluminum or aluminum alloy parts using lasers:

[0010] This method enables contrast marking, where the contrast between the laser-marked mark and the treated substrate is significantly increased to improve the visibility, legibility, and readability of the mark in any environment; and / or

[0011] This method enables high-precision marking to achieve stable quality resistant to abrasive and corrosive environments; and / or

[0012] This method is suitable for small, fine markings on small surfaces, such as DMC (Data Matrix Code) and UDI (Unique Device Identifier) ​​codes; and / or

[0013] - This method enables the labeled parts to withstand corrosive environments, salt spray, and biological corrosion without requiring additional post-labeling chemical conversion treatment steps. Summary of the Invention

[0014] The object of this invention is to meet these needs by providing a method for surface marking of aluminum or aluminum alloy parts, particularly regarding the resistance of the treated parts to corrosion and bio-corrosion, as well as the visibility / readability of the markings, said method comprising at least the following steps:

[0015] A) Anodizing step;

[0016] B) The step of sealing the anode layer formed on the component at the end of step A).

[0017] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 Mohms, preferably equal to or greater than 0.1 Mohms, more preferably equal to or greater than 10 Mohms, and in an aqueous solution of 1 to 500 g / L of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C.

[0018] or

[0019] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, at a temperature between 60°C and 100°C.

[0020] D) Marking steps using fiber laser beams having one or more of the following characteristics,

[0021] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0022] - Pulse duration is between 0.5 ns and 10 ns.

[0023] - The laser frequency is between 400kHz and 3000kHz.

[0024] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0025] -Speed ​​between 1000mm / s and 3000mm / s

[0026] - Line spacing is between 0.0001mm and 0.1mm, and

[0027] - The marking time is between 4 seconds and 200 seconds.

[0028] Step B is mandatory because without a seal, resistance to corrosion and biodegradation is no longer required. However, Step B has two options: sealing with silicates or sealing with boiling water alone (without silicates). The first will enable subsequent engraving (the subject of this patent application) to guarantee resistance to corrosion and biodegradation, while the second will only guarantee resistance to corrosion of the resulting engraving.

[0029] In a preferred embodiment, the fiber laser is a master oscillator power amplifier (MOPA) laser.

[0030] The surface markings on aluminum or aluminum alloy parts produced by the method according to the invention exhibit excellent contrast; that is, the contrast between the laser-marked and treated surfaces is significantly increased, thus improving the visibility and readability of the markings regardless of environmental conditions and brightness. Furthermore, aluminum or aluminum alloy parts with markings produced by the method of the invention exhibit good resistance to biological corrosion, corrosion, and especially salt spray and corrosive or acidic environments, even without any subsequent chemical treatment after marking.

[0031] Another object of the present invention relates to the use of the marking method according to the invention for manufacturing or marking aluminum or aluminum alloy parts for use in the aerospace, automotive, railway, watchmaking, medical, nuclear and petroleum industries, etc. Attached Figure Description

[0032] Further features and advantages of the invention will become apparent from the following detailed description, in which reference is made to the accompanying drawings, wherein:

[0033] Figure 1 A diagram of an apparatus for performing a biocorrosion test on a sample treated by the method of the present invention, according to section 4.7.19 of standard MIL-C-27725B. Detailed Implementation

[0034] The object of this invention is to meet these requirements by providing a method for surface marking of aluminum or aluminum alloy parts, particularly in terms of the resistance of the treated parts to corrosion and bio-corrosion, and the visibility / readability of the markings, said method comprising at least the following steps:

[0035] A) Anodizing step;

[0036] B) The step of sealing the anode layer formed on the component at the end of step A).

[0037] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C, in a solution of 1 to 500 g / L.

[0038] or

[0039] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms at a temperature between 60°C and 100°C.

[0040] D) Marking steps using fiber laser beams having one or more of the following characteristics,

[0041] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0042] - Pulse duration is between 0.5 ns and 10 ns.

[0043] - The laser frequency is between 400kHz and 3000kHz.

[0044] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0045] -Speed ​​between 1000mm / s and 3000mm / s

[0046] - Line spacing is between 0.0001mm and 0.1mm, and

[0047] - The marking time is between 4 seconds and 200 seconds.

[0048] The method according to the invention enables comparative marking of aluminum or aluminum alloy parts, making the marked parts resistant to corrosion, especially in salt spray environments and resistant to biological corrosion.

[0049] Anodizing step A) is performed under the conditions described in application FR 3106837.

[0050] The sealing step B) is carried out under the conditions described in application FR 3106837 when it occurs as described above in deionized water and an aqueous solution of alkali metal or alkaline earth metal silicates.

[0051] According to a preferred embodiment of the invention, the anodizing step A) is an anodizing step in which the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14 and 21°C during the step.

[0052] A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage that rises at a rate of less than 1V / min until it reaches a voltage value known as a plateau value between 5V and 13V.

[0053] Once a voltage value known as the plateau value is reached, the applied voltage is maintained at the plateau value for a sufficient period of time to obtain an anode layer with a thickness between 2 μm and 7 μm on the surface of the component.

[0054] The voltage applied to the immersed component can be maintained at a plateau value for a period of time between 20 and 80 minutes.

[0055] The voltage value known as the plateau value can be between 6V and 10V.

[0056] This type of anodizing is a fine OAS (fine sulfuric acid anodizing).

[0057] In the method of the present invention, the anodizing step A) can also be an anodizing step of the TSA, OAS, PSAA, BS AA or OAC type. These anodizing processes are well known to those skilled in the art and are described in the following literature: https: / / www.a3ts.org / actualite / commissions-techniques / fiches-techniques-traitement-surface / anodisation-sulfo-tartrique-oast-tartric-sulfuric-anodizing-tsa / for TSA (tartaric acid-sulfuric acid anodizing), https: / / www.a3ts.org / actualite / commissions-techniques / fiches-techniques-traitement-surface / anodisation-sulfurique-version-5-2 / for OAS (sulfuric acid anodizing), https: / / www.anoplate.com / finishes / boric-sulfuic-acide-anodize-bsaa / for BSAA (boric acid-sulfuric acid anodizing), http: / / www.metroplating.co.uk / phosphoric-acid-anodizing.php / for PSAA (phosphoric acid-sulfuric acid anodizing), etc.

[0058] Preferably, the anodizing in step A) is fine OAS.

[0059] The method of the present invention is particularly applicable to aluminum and aluminum alloy parts selected from the group consisting of: 2014, 2017A, 2024, 2214, 2219, 2618, AU5NKZr, 7175, 5052, 5086, 6061, 6063, 7010, 7020, 7050, 7050T7451, 7055T77, 7068, 7085T7651, 7075, 7175 and 7475, AS7G06, AS7G03, AS10G, AS9U3, where AS7G06 and AS10G are obtained by different production methods, namely additive manufacturing.

[0060] As shown, the voltage profile applied to the component includes an initial voltage of 0V increasing at a rate of less than 1V / min, preferably from 0.3V / min to 0.7V / min, until a voltage value known as a plateau value is reached, which is between 5V and 13V, preferably between 6V and 10V. The voltage applied to the component immersed in the bath is then maintained at the plateau value for an appropriate period of time to obtain an anode layer on the surface of the component with a thickness between 2μm and 7μm, for example, an alumina / aluminum hydroxide layer with a thickness of about 5μm.

[0061] According to an embodiment of the invention, the voltage applied to the immersion component is maintained at a plateau value for a period of time between 20 and 80 minutes, preferably between 30 and 60 minutes.

[0062] In the anodizing step A) according to a preferred embodiment of the present invention, the sulfuric acid concentration in the bath is preferably between 160 g / L and 220 g / L, for example equal to 190 g / L.

[0063] In the anodizing step A) according to a preferred embodiment of the present invention, the temperature of the bath can be between 10°C and 25°C, preferably between 14°C and 21°C, for example 18°C.

[0064] Anodizing step A) is followed by step B), which is the step of sealing the anodic layer formed on the component during step A).

[0065] According to one embodiment of the present invention, the method includes an anodizing step A), a sealing step B), and a marking step D.

[0066] In a variant of the invention, the sealing in step B) is performed in the following aqueous solution.

[0067] - Deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and

[0068] Alkali metal or alkaline earth metal silicates ranging from -1 g / L to 500 g / L.

[0069] Alkali metal or alkaline earth metal silicates can be selected from the group consisting of lithium silicate, sodium silicate, potassium silicate, calcium silicate and magnesium silicate.

[0070] The water quality in the sealing bath is important because it affects the resistance of the anolyte layer formed on the surface components to biocorrosion. Purer water, such as water with a resistivity of 10 MOhms or higher, may provide better performance over time than water with a resistivity less than 10 MOhms. According to a preferred variant, deionized water is assembly water, i.e., water used to fill the active bath during assembly / filling, said water having a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms.

[0071] During the sealing step B), the concentration of alkali metal or alkaline earth metal silicates in the solution is preferably between 15 g / L and 40 g / L, for example, equal to 23 g / L.

[0072] In another variation, the sealing in step B) is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms.

[0073] In all variations and embodiments of the present invention, the temperature of the sealing solution in step B) can be between 60°C and 100°C, preferably between 97°C and 100°C, for example 98°C.

[0074] In all variations and embodiments of the invention, the duration of sealing step B) is between 1 minute and 40 minutes, preferably between 15 minutes and 40 minutes, for example, 30 minutes. This applies to cases where sealing is performed using only silicate-free water as described above.

[0075] When sealed with silicate, the duration is 15 to 25 minutes, preferably 20 minutes.

[0076] According to one embodiment of the present invention, after step A) and before the silicate sealing step (step B), the component is immersed in step A1) in the following water bath.

[0077] - In a water bath containing trivalent chromium salts, the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O and CrK(SO4)2·xH2O (step A1-1);

[0078] Then optionally

[0079] - This can be carried out in a water bath containing an oxidizing compound selected from the group consisting of hydrogen peroxide (H2O2), ammonium fluoride (NH4F), potassium fluorozirconate (K2ZrF6), potassium permanganate (KMnO4), and sodium permanganate (NaMnO4) (steps A1-2).

[0080] Trivalent chromium salts can be one of the following commercially available products: Surtec 650 from SURTEC, Lanthane 613.3 from COVENTYA, TCS from SOCOMORE, and Bonderite MNT 65000 from HENKEL.

[0081] The oxidizing compound can be, for example, a product of SOCOMORE, called PACS.

[0082] In immersion step A1), steps A1-1) and A1-2) can be performed in the following order: step A1-1), then step A1-2). Immersion step A1) can also be a single step A1-1), without the subsequent step A1-2).

[0083] In steps A1-1) and A1-2) as described above, the temperature of the water bath containing the trivalent chromium salt and the temperature of the water bath containing the oxidizing compound are between 20°C and 80°C, preferably between 20°C and 60°C. The temperatures of the two baths may be the same or different.

[0084] The immersion time in each bath in step A1) can be the same or different. It can be between 5 minutes and 40 minutes, preferably between 5 minutes and 20 minutes.

[0085] The pH of a bath containing trivalent chromium salts can be between 3 and 4.5, preferably between 3 and 4, for example, 3.5.

[0086] The concentration of trivalent chromium salt in the bath is preferably between 0.5 g / L and 500 g / L.

[0087] The pH of baths containing oxidizing compounds is between 3 and 6.

[0088] The concentration of the oxidizing compound in the bath is preferably between 0.1 g / L and 500 g / L.

[0089] According to another embodiment of the invention, the method also includes a final hydrothermal seal before step D) and after the seal according to step B), which will be referred to as step C). The final hydrothermal seal C) is performed in deionized water with a resistivity equal to or greater than 0.01 Mohms, preferably equal to or greater than 0.1 Mohms, more preferably equal to or greater than 10 Mohms, and at a temperature greater than 96°C (e.g., between 97°C and 100°C).

[0090] In the final hydrothermal seal (C), the component is immersed in deionized water with a resistivity advantageously equal to or greater than 10 MOhms. The immersion time in this step can be from 10 to 30 minutes, preferably from 15 to 25 minutes.

[0091] Marking step D) is performed by a fiber laser beam having one or more of the following characteristics:

[0092] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0093] - Pulse duration is between 0.5 ns and 10 ns.

[0094] - The laser frequency is between 400kHz and 3000kHz.

[0095] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0096] -Speed ​​between 1000mm / s and 3000mm / s

[0097] - Line spacing is between 0.0001mm and 0.1mm, and

[0098] - The marking time is between 4 seconds and 200 seconds.

[0099] The inventors discovered that, following the laser fiber treatment in step D), the corrosion behavior of aluminum and aluminum alloy components showed that:

[0100] (1) Skillful and appropriate selection of parameters can be used to produce surface contrast marks with different geometries and shapes;

[0101] (2) The ultrafast and efficient laser processing according to step D) produces contrasting surface markings without affecting and / or altering the microstructure of the aluminum or aluminum alloy parts.

[0102] In fact, the laser treatment in step D) can produce dark or even black markings, thus creating a contrast on aluminum or aluminum alloy parts. Therefore, these markings have high contrast and are easy to read under all lighting conditions.

[0103] The marking in step D) involves marking the anodized surface with fiber-reinforced laser beams, producing a dark, high-contrast imprint within the anodized layer without penetrating it. This marking can be viewed as a laser processing method that produces extremely deep, high-contrast markings on a surface without removing any material. Extremely short laser pulses generate nanoscale structures on the surface. This microstructure reduces light scattering, resulting in markings with a deep and stable blackening.

[0104] Due to the skillful selection of parameters, step D) avoids affecting the component and keeps the marking within the thickness of the oxide layer. Unlike currently known and used marking methods, components marked under the conditions of step D) do not require post-marking treatment (e.g., by chemical conversion) to be protected from corrosion and biodegradation because the marking is contained within the anodic layer and does not reach the (below) aluminum substrate. Therefore, the marked components exhibit improved resistance to biodegradation and corrosion (especially when exposed to salt and salt spray) compared to other engraving / marking techniques.

[0105] Marking step D) can be performed using any type of fiber laser with the above-described characteristics.

[0106] In the case of fiber lasers, the amplification medium is an optical fiber doped with rare earth elements (such as samarium, erbium, ytterbium, neodymium, dysprosium, praseodymium, thulium, and holmium). The wavelength obtained depends on the element chosen. Some wavelengths are given as examples for several elements: samarium 0.6 μm; ytterbium 1.05 μm; erbium 1.55 μm; thulium 1.94 μm; holmium 2.1 μm.

[0107] The small spot size produced by the fiber laser beam limits the amount of energy converted into heat. This means that the treated surface is protected from damage by heat or breakage.

[0108] Another advantage is that fiber lasers are energy-efficient.

[0109] In one embodiment of the invention, the fiber laser is a system in which the amplification medium is an optical fiber doped with ytterbium.

[0110] In a preferred embodiment, the marking in step D) is performed using a fiber laser, which is a master oscillator power amplifier (MOPA) laser. Examples of such lasers include the TF 420 laser from TECHNIFOR or the SpeedMarker 700 laser from TROTEC.

[0111] As previously described, the marking in step D) is performed on the thickness of the aluminum oxide / hydroxide layer without removing any material or reaching the part itself. Therefore, the laser marking in step D) is performed on an aluminum oxide / hydroxide layer at least 3 μm thick, for example at least 4 μm thick, for example 4 μm to 6 μm thick. Preferably, the laser marking in step D) is performed on an aluminum oxide / hydroxide layer with a thickness of approximately 5 μm.

[0112] Step D) can be performed using a fiber laser with a wavelength greater than 800 nm (e.g., 1064 nm).

[0113] The duration of the laser pulse can be between 0.5 ns and 10 ns, preferably between 1 ns and 7 ns, and more preferably between 1 ns and 4 ns.

[0114] The laser frequency can be between 400kHz and 3000kHz.

[0115] The power of fiber lasers ranges from 5W to 80W, for example, from 8W to 20W.

[0116] The speed of a fiber laser beam can range from 1000 mm / s to 3000 mm / s.

[0117] The line spacing can be between 0.0001mm and 0.1mm.

[0118] The marking time in step D) can be between 4 seconds and 200 seconds.

[0119] A laser beam is pulsed and releases energy at specific time intervals. Velocity and line spacing are two parameters that determine the distance between two pulses.

[0120] In one embodiment of the present invention, a method for marking the surface of an aluminum or aluminum alloy component includes the following steps:

[0121] A) Anodizing step, during which the component is immersed in a water bath containing sulfuric acid at a concentration between 150 g / L and 250 g / L and at a temperature between 14°C and 21°C.

[0122] A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage rise at a rate of less than 1V / min until a voltage value known as a plateau value between 5V and 13V is reached; and

[0123] B) The step of sealing the anode layer formed on the component at the end of step A).

[0124] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C, in a solution of 1 to 500 g / L.

[0125] or

[0126] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms, at a temperature between 60°C and 100°C; and

[0127] D) Fiber laser marking step, wherein the step has one or more of the following characteristics:

[0128] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0129] - Pulse duration is between 0.5 ns and 10 ns.

[0130] - The excitation frequency is between 400kHz and 3000kHz.

[0131] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0132] -Speed ​​between 1000mm / s and 3000mm / s

[0133] - Line spacing is between 0.0001mm and 0.1mm, and

[0134] - The marking time is between 4 seconds and 200 seconds.

[0135] In another embodiment of the present invention, the method for marking the surface of an aluminum or aluminum alloy component includes the following steps:

[0136] A) Anodizing step, during which the component is immersed in a water bath containing sulfuric acid at a concentration between 150 g / L and 250 g / L and at a temperature between 14°C and 21°C.

[0137] A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage that rises at a rate of less than 1V / min until it reaches a voltage value known as a plateau value between 5V and 13V.

[0138] A1) The step of immersing the component in the following water bath.

[0139] - A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O and CrK(SO4)2·xH2O (step A1-1);

[0140] Then (optionally)

[0141] - A water bath containing an oxidizing compound selected from the group consisting of hydrogen peroxide (H₂O₂), ammonium fluoride (NH₄F), potassium fluorozirconate (K₂ZrF₆), potassium permanganate (KMnO₄), and sodium permanganate (NaMnO₄) (steps A1-2); and

[0142] B) The step of sealing the anode layer formed on the component at the end of step A).

[0143] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C, in a solution of 1 g / L to 500 g / L.

[0144] or

[0145] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms, at a temperature between 60°C and 100°C; and

[0146] D) Fiber laser marking step, wherein the step has one or more of the following characteristics:

[0147] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0148] - Pulse duration is between 0.5 ns and 10 ns.

[0149] - The laser frequency is between 400kHz and 3000kHz.

[0150] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0151] -Speed ​​between 1000mm / s and 3000mm / s

[0152] - Line spacing is between 0.0001mm and 0.1mm, and

[0153] - The marking time is between 4 seconds and 200 seconds.

[0154] In another embodiment of the present invention, the method for marking the surface of an aluminum or aluminum alloy component includes the following steps:

[0155] A) Anodizing step, during which the component is immersed in a water bath containing sulfuric acid at a concentration between 150 g / L and 250 g / L and at a temperature between 14°C and 21°C.

[0156] A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage that rises at a rate of less than 1V / min until it reaches a voltage value known as a plateau value between 5V and 13V.

[0157] A1) The step of immersing the component in the following water bath.

[0158] - A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O and CrK(SO4)2·xH2O (step A1-1);

[0159] Then (optionally)

[0160] - A water bath containing an oxidizing compound selected from the group consisting of hydrogen peroxide (H2O2), ammonium fluoride (NH4F), potassium fluorozirconate (K2ZrF6), potassium permanganate (KMnO4), and sodium permanganate (NaMnO4) (step A1-2);

[0161] B) The step of sealing the anode layer formed on the component at the end of step A).

[0162] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C, in a solution of 1 g / L to 500 g / L.

[0163] or

[0164] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms, at a temperature between 60°C and 100°C; and

[0165] C) The final hydrothermal seal is performed in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and at a temperature between 97°C and 100°C; and

[0166] D) Fiber laser marking step, wherein the step has one or more of the following characteristics:

[0167] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0168] - Pulse duration is between 0.5 ns and 10 ns.

[0169] - The laser frequency is between 400kHz and 3000kHz.

[0170] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0171] -Speed ​​between 1000mm / s and 3000mm / s

[0172] - Line spacing is between 0.0001mm and 0.1mm, and

[0173] - The marking time is between 4 seconds and 200 seconds.

[0174] In another embodiment of the present invention, the method for marking the surface of an aluminum or aluminum alloy component includes the following steps:

[0175] A) Anodizing step, during which the component is immersed in a water bath containing sulfuric acid at a concentration between 150 g / L and 250 g / L and at a temperature between 14°C and 21°C.

[0176] A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage that rises at a rate of less than 1V / min until it reaches a voltage value known as a plateau value between 5V and 13V.

[0177] A1) The step of immersing the component in the following water bath.

[0178] - A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O, and CrK(SO4)2·xH2O (step A1-1); and

[0179] B) The step of sealing the anode layer formed on the component at the end of step A).

[0180] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C, in a solution of 1 g / L to 500 g / L.

[0181] or

[0182] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms, at a temperature between 60°C and 100°C; and

[0183] D) Fiber laser marking step, wherein the step has one or more of the following characteristics:

[0184] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0185] - Pulse duration is between 0.5 ns and 10 ns.

[0186] - The laser frequency is between 400kHz and 3000kHz.

[0187] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0188] -Speed ​​between 1000mm / s and 3000mm / s

[0189] - Line spacing is between 0.0001mm and 0.1mm, and

[0190] - The marking time is between 4 seconds and 200 seconds.

[0191] In another embodiment of the present invention, the method for marking the surface of an aluminum or aluminum alloy component includes the following steps:

[0192] A) Anodizing step, during which the component is immersed in a water bath containing sulfuric acid at a concentration between 150 g / L and 250 g / L and at a temperature between 14°C and 21°C.

[0193] A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage that rises at a rate of less than 1V / min until it reaches a voltage value known as a plateau value between 5V and 13V.

[0194] Im) is the step of immersing the anodized component at the end of step A) in an organic or inorganic dye bath, and then optionally...

[0195] A1) The step of immersing the component in the following water bath.

[0196] - A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O and CrK(SO4)2·xH2O (step A1-1);

[0197] Then (optionally)

[0198] - A water bath containing an oxidizing compound selected from the group consisting of hydrogen peroxide (H2O2), ammonium fluoride (NH4F), potassium fluorozirconate (K2ZrF6), potassium permanganate (KMnO4), and sodium permanganate (NaMnO4) (steps A1-2); and optionally,

[0199] B) The step of sealing the anode layer formed on the component at the end of step A).

[0200] The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, more preferably equal to or greater than 10 MOhms, and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C, in a solution of 1 g / L to 500 g / L.

[0201] or

[0202] The process is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms, preferably equal to or greater than 0.1 MOhms, and more preferably equal to or greater than 10 MOhms, at a temperature between 60°C and 100°C; and

[0203] D) Fiber laser marking step, wherein the step has one or more of the following characteristics:

[0204] - Wavelength greater than 800nm, for example, equal to 1064nm.

[0205] - Pulse duration is between 0.5 ns and 10 ns.

[0206] - The laser frequency is between 400kHz and 3000kHz.

[0207] - Power consumption is between 5W and 80W, for example, between 8W and 20W.

[0208] -Speed ​​between 1000mm / s and 3000mm / s

[0209] - Line spacing is between 0.0001mm and 0.1mm, and

[0210] - The marking time is between 4 seconds and 200 seconds.

[0211] Step Im) Following step A), any technique known to those skilled in the art can be used. For example, it can be achieved in a dye bath suitable for surface treatment provided by companies such as Clariant. As an example, we can mention an organic dye, Sanodal Blue (from Clariant), at a concentration of 3 g / L, in which 2 g / L of sodium acetate must be added, the pH must be between 5 and 6, the temperature between 40°C and 65°C, preferably equal to 50°C, and the duration between 5 minutes and 35 minutes, preferably equal to 20 minutes. The active ingredient of the organic dye is anthraquinone molecules.

[0212] In all embodiments, before the component is subjected to the surface treatment method of the present invention, and thus before the anodizing step A), the component may be subjected to a surface preparation step by degreasing and / or immersion to remove grease, dirt and oxides present on its surface.

[0213] The preliminary steps of this surface preparation may include one or more of the following operations:

[0214] Solvent degreasing to dissolve grease on the surface of the parts. This operation can be achieved by soaking, spraying, or any other method known to those skilled in the art;

[0215] - Alkaline degreasing to dissolve grease on the surface of the parts. This operation can be achieved by soaking, spraying, or any other technique known to those skilled in the art;

[0216] - Alkaline pickling to dissolve naturally occurring oxides on the surface of the component. This operation can be achieved by immersion, spraying, or any other technique known to those skilled in the art. At the end of this operation, the component is covered with a powdery layer formed by the oxidation products of intermetallic compounds, which must be removed by an acidic pickling step;

[0217] - Acidic pickling to dissolve naturally occurring oxides on the surface of the component and / or oxide layers formed on the surface of the component during the alkaline pickling step. This operation can be achieved by immersion, spraying, or any other technique known to those skilled in the art.

[0218] These steps are described in detail, for example, in WO 2013 / 117759.

[0219] Intermediate rinsing (especially with softened water) is preferably performed between the above-described sequential steps and before the component is anodized.

[0220] The method of the present invention is of great interest in any type of industry that requires contrast markings for aluminum or aluminum alloy parts and good resistance to corrosion, bio-corrosion, salt spray and salt exposure.

[0221] Once a mark is made on an aluminum or aluminum alloy part (such as Alloy 2024T3) using, for example, the method of the present invention (without physicochemical post-treatment),

[0222] - If a salt spray test is performed on the component (according to ISO 9227, exposure for 168 hours), and no corrosion is observed at the end of the test, while ensuring the legibility and visibility of the markings, and

[0223] - If the component is subjected to a 15-day immersion biocorrosion test according to standard MIL-C-27725B 4.7.19, the markings should remain uncorroded and legible at the end of the test. It should be noted that resistance to biocorrosion is only guaranteed if the scope and related variations include at least the silicate sealing steps described above.

[0224] It should be noted that, without physicochemical post-treatment, contrast or non-contrast laser markings applied to aluminum or aluminum alloy (such as 2024T3 alloy) parts (penetrating the oxide layer) will show signs of corrosion before meeting the 168-hour salt water exposure requirement according to ISO 9227.

[0225] One advantage of the markings using the method described in this invention is their visual stability regardless of the viewing angle. The very strong, uniform contrast from all angles is due to the periodic nanostructures that reflect and absorb light while scattering it as widely as possible. This characteristic is particularly representative of quality assurance in industries such as watchmaking and automobiles, which implement many apparent components.

[0226] The dark, high-contrast markings produced by this method greatly improve the visibility and readability of marking details, whether manually or automatically.

[0227] Furthermore, the marking method of the present invention is applicable to small and fine markings, or to DMC (Data Matrix Code) and UDI (Unique Device Identifier) ​​codes on small surfaces.

[0228] For example, European regulations on medical devices and US FDA (Food and Drug Administration) regulations require medical technology products to bear a UDI (Unique Device Identifier) ​​code. This UDI code ensures the traceability of these medical technology products and remains clearly legible over time. The marking made using the method of this invention makes it highly compliant with UDI-compatible marking requirements. UDI codes, especially very small ones, can remain clearly legible for a long time due to their resistance to corrosion, their stability under all viewing angles, and their contrast, or even deep black color.

[0229] Another object of the present invention relates to the use of the marking method according to the invention for manufacturing or marking aluminum or aluminum alloy parts for use in the aerospace, automotive, railway, watchmaking, medical, nuclear and petroleum industries.

[0230] Example

[0231] Example 1:

[0232] Surface marking methods for aluminum alloy parts

[0233] The aluminum alloy parts 2024T3 and AS7G06T6, with dimensions of 120mm×60mm×2mm and laminated on one of their sides, are processed according to the following method.

[0234] First, perform the surface preparation steps for the components in sequence:

[0235] - Alkaline degreasing, by immersing the parts in a bath of ALUMAL CLEAN 101 (from COVENTYA) at 60°C for 20 minutes;

[0236] - Rinse with tap water or softened water;

[0237] - Acid pickling: This involves immersing the parts in a solution of ALUMAL DEOX 411 (from COVENTYA).

[0238] Rinse with tap water or softened water.

[0239] The pickled and rinsed parts are then subjected to the anodizing method according to the invention, during which the parts are immersed in a water bath containing sulfuric acid at a concentration between 160 g / L and 220 g / L, for example, equal to 190 g / L. This bath is conducted and maintained at a temperature of 18°C. A DC voltage is applied to the immersed parts according to the following voltage curve: the voltage increases from 0 V at a rate of 0.7 V / min until a voltage value of 10 V, referred to as the plateau value, is reached. The voltage is maintained at the plateau value for 40 minutes. An anolyte layer of 3 μm to 6 μm thickness is formed on the surface of the parts.

[0240] As a comparative example, the same parts that had undergone the same surface preparation operations were anodized using conventional methods of chromic acid anodizing (OAC) and fine sulfuric acid anodizing (fine OAS). The operating conditions for these anodizing processes are shown in [Table 1].

[0241] [Table 1]

[0242]

[0243] According to standard ISO2360, the thickness of the anode layer formed on the component is measured by eddy current.

[0244] The anodized components are then rinsed once or multiple times, preferably with softened water, followed by the sealing operation according to the invention under the following conditions and sequence:

[0245] -Steps A1.1) and A1.2): Immerse the component sequentially in a water bath containing 29% by volume of trivalent chromium salt (potassium chromium(III) sulfate, chemical formula KCr(SO4)2), at a temperature of 40°C and a pH of 3.9 for 20 minutes, then...

[0246] In a water bath containing 7% H2O2 at 25°C and pH 4.2 for 5 minutes;

[0247] Step B): Seal the components by immersing them at the end of the first two operations in a fixed aqueous solution of deionized water with a resistivity of 10 MOhms and sodium silicate at a temperature of 98°C for 20 minutes.

[0248] Between each sealing step, rinse with softened water at a temperature of approximately 20°C for 1 minute.

[0249] Non-drilling marking step D (without affecting the component) using a MOPA fiber laser beam is performed under the conditions specified in [Table 2] using a SpeedMarker 700 laser from TROTEC:

[0250] [Table 2]

[0251]

[0252] Alodine conversion refers to the chemical conversion of Alodine 1200, a chemical method specifically designed for long-term protection of aluminum or aluminum alloy surfaces from oxidation. Alodine 1200 treatments have been developed to protect surfaces that do not require paint finishes or only require partial finishes (resistance to salt spray >168 hours).

[0253] Due to the perfect chemical stability of the treated surface, it ensures maximum adhesion and excellent durability of the applied finish.

[0254] Alodine 1200, used for hardening treatment, forms a protective coating on aluminum or alloys with very little excess thickness. The color of this coating varies from yellow to brown, depending on the type of alloy or the purity of the metal.

[0255] Alodine 1200 is certified to standard MIL C 5541.

[0256] Resistance to biological corrosion

[0257] At the end of these operations, a sealed and marked anodic layer is obtained on each treated component. Following treatment, the components are subjected to an immersion test in a medium representing biocorrosion, following the protocol in §4.7.19 of standard MIL-27725B. A schematic diagram of the assembly (with various components) for biocorrosion testing according to §4.7.19 of standard MIL-27725B is shown below. Figure 1 As shown.

[0258] The results are visually evaluated by removing components from the medium to check for the visibility and legibility of markings and any signs of damage caused by the processing and / or the medium (the underlying phase) to the substrate. Visual degradation can be confirmed by measuring the ohmic resistivity of the layer; when the ohmic resistivity is not infinite, it highlights the deterioration of the layer, which can persist to the substrate.

[0259] Before testing, the ohmic resistivity method helps predict the fact that if current passes through the two engraved points, resistance to biocorrosion will not be met. On the other hand, if the markings are not attacked, there is no requirement after the biocorrosion test.

[0260] This method is systematically performed after any potential corrosion indicators have been tested for biocorrosion, and only at the end of the 15-day biocorrosion test.

[0261] Method for measuring resistance using an ohmmeter:

[0262] A multimeter can be used to measure resistance. Therefore, the multimeter must be used in ohmmeter mode.

[0263] Using a multimeter in ohmmeter mode:

[0264] Terminal selection: COM terminal and terminal with Ω symbol.

[0265] Connection: At the end of the test, connect the multimeter directly to two points on the sample, in the area where the two phases of the medium are in contact with the lower phase.

[0266] Range: Select the maximum range, then decrease it until you find the minimum range that is higher than the measured value.

[0267] [Table 3] summarizes the results of testing the resistance to biocorrosion of different surface treatments with the number of days of immersion in a two-phase medium.

[0268] [Table 3]

[0269] "NOK" means that the resistance to biological corrosion does not meet the reading or expected standards.

[0270]

[0271]

[0272] Pitting corrosion is a type of localized corrosion that results in irregularly shaped cavities on the surface of aluminum alloy parts. These cavities appear when the aluminum alloy parts come into contact with an aqueous solution containing halide ions (most commonly chloride ions). Based on the results shown in [Table 3], it is clear that the 168-hour resistance according to ISO 9227 was good for all three samples. No corrosion was observed at the end of the test, and the markings remained clearly legible.

[0273] Various black mark tests were performed on different substrates (2024T3 and AS7G06T6). Some marks remained in the layer and did not reach the substrate, while others reached the substrate. The latter case could be detected by measuring the current at two points on the mark (if current flowed, the layer had been completely penetrated).

[0274] 1) After marking and before exposure to salt spray according to ISO 9227, anodize with sulfuric acid (as described above). and / or a fine OAS test tube according to patent application number FR3106837)

[0275] For the 2024T3 alloy sample (fine OAS and silicate seal) and the AS7G06T6 alloy sample (standard fine OAS - no silicate), the markings are intact and clearly legible.

[0276] 2) After marking and after 168 hours of exposure to salt spray according to ISO 9227, anodize with sulfuric acid (e.g.) The fine OAS test tube described above and / or according to patent application number FR3106837)

[0277] For the 2024T3 alloy sample (fine OAS and silicate seal), no corrosion was detected on the markings (which were electrical insulation markings before testing) after exposure to salt spray. The markings remained intact and clearly legible.

[0278] For the AS7G06T6 alloy sample (fine OAS standard - no silicates), no corrosion was detected on the markings (which were electrically insulating before testing) after exposure to salt spray. The markings remained intact and clearly legible. However, significant corrosion was detected on other markings (which were conductive before testing, indicating that the laser markings had penetrated the anodic layer and reached the substrate).

[0279] 3) After a 15-day immersion biocorrosion test according to §4.7.19 of standard MIL-C-27725B, the sulfur... Fine OAS test tubes for acid anodizing (as described above and / or according to patent application number FR3106837)

[0280] For the 2024T3 alloy sample (fine OAS and silicate seal) and the AS7G06T6 alloy sample (standard fine OAS - no silicate), no corrosion was detected on the markings after 15 days of immersion according to §4.7.19 of standard MIL-C-27725B. The markings remained intact and remained clearly legible and contrasting.

[0281] These tests clearly demonstrate that the components treated using the methods described above have achieved the desired objectives, namely,

[0282] - Generate contrast markers to improve the visibility, readability, and readableness of the markers.

[0283] -Remove the requirement for post-labeling chemical transformation (e.g., with Bonderite MCR 1200).

[0284] - Achieve high-contrast laser marking with at least 168 hours of resistance to neutral salt spray according to ISO 9227.

[0285] - Obtain contrast laser markings that resist biocorrosion after 15 days of immersion in §4.7.19 of standard MIL-C-27725B.

[0286] Aviation requirements for resistance to salt spray (168h exposure according to ISO 9227) and resistance to biocorrosion after 15 days of immersion according to §4.7.19 of standard MIL-C-27725B are also met by the marking method of the present invention.

[0287] In summary, the method for marking aluminum or aluminum alloy parts according to the present invention facilitates the reading of the markings using a digital barcode reader. The markings on these parts ensure that they can withstand salt corrosion without requiring post-chemical transformation and are also resistant to biological corrosion.

[0288] Therefore, the marking method according to the invention is of great interest in all industries that use data matrices or markers that require minimal contrast for easy reading and resistance to (biological) corrosion, such as general aerospace equipment, nuclear industry, offshore (oil) industry, automotive industry, railway industry, etc.

Claims

1. A method for marking the surface of an aluminum or aluminum alloy component, comprising at least the following steps: A) Anodizing step; B) The step of sealing the anode layer formed on the component at the end of step A). The sealing is carried out in deionized water with a resistivity equal to or greater than 0.01 MOhms and in an aqueous solution of alkali metal or alkaline earth metal silicates at a temperature between 60°C and 100°C. or The experiment was conducted in deionized water with a resistivity equal to or greater than 0.01 MOhms at a temperature between 60°C and 100°C. D) Marking steps using fiber laser beams having one or more of the following characteristics, - Wavelength greater than 800 nm - The pulse duration is between 0.5 ns and 10 ns. - The laser frequency is between 400 kHz and 3000 kHz. - Power consumption is between 5 W and 80 W. - Speeds range from 1000 mm / s to 3000 mm / s. - Line spacing between 0.0001 mm and 0.1 mm, and - The marking time is between 4 seconds and 200 seconds.

2. The method according to claim 1, characterized in that, Step A) is an anodizing of the following types: tartaric acid-sulfuric acid anodizing, sulfuric acid anodizing, phosphoric acid-sulfuric acid anodizing, boric acid-sulfuric acid anodizing, or OAC-chromic acid anodizing.

3. The method according to claim 1, characterized in that, Step A) is anodizing of the fine sulfuric acid anodizing type.

4. The method according to any one of claims 1 to 3, characterized in that, The anodizing step A) is an anodizing step in which the component is immersed in a water bath containing sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C during the anodizing step. A DC voltage is applied to the immersed component according to a voltage curve, which includes a voltage that rises at a rate of less than 1 V / min until it reaches a voltage value known as a plateau value between 5 V and 13 V.

5. The method according to any one of claims 1 to 3, characterized in that, The aluminum alloy is selected from the group consisting of 2014, 2017A, 2024, 2214, 2219, 2618, AU5NKZr, 7175, 5052, 5086, 6061, 6063, 7010, 7020, 7050, 7050 T7451, 7055 T77, 7068, 7085 T7651, 7075, 7175 and 7475, AS7G06, AS7G03, AS10G, AS9U3, and AS7G06, with AS7G06 and AS10G obtained by additive manufacturing.

6. The method according to any one of claims 1 to 3, characterized in that, The alkali metal or alkaline earth metal silicate is selected from the group consisting of lithium silicate, sodium silicate, potassium silicate, calcium silicate and magnesium silicate.

7. The method according to any one of claims 1 to 3, characterized in that, Step D) is performed using a fiber laser, which is a system in which the amplification medium is an optical fiber doped with ytterbium.

8. The method according to any one of claims 1 to 3, characterized in that, Step D) is performed using a fiber laser, which is a master oscillator power amplifier laser or a MOPA.

9. The method according to any one of claims 1 to 3, characterized in that, The method includes step A1), which involves immersing the component in a water bath after step A) and before step B) of the silicate sealing step. - Step A1-1: A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O and CrK(SO4)2·xH2O.

10. The method according to any one of claims 1 to 3, characterized in that, The method includes step A1), which involves immersing the component in a water bath after step A) and before step B) of the silicate sealing step. - Step A1-1): A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O, and CrK(SO4)2·xH2O; then - Step A1-2): A water bath containing an oxidizing compound selected from the group consisting of hydrogen peroxide, ammonium fluoride, potassium fluorozirconate, potassium permanganate, and sodium permanganate.

11. The method according to any one of claims 1 to 3, characterized in that, The method includes step C, a final hydrothermal seal, performed in deionized water with a resistivity equal to or greater than 0.01 MOhms at a temperature greater than 96°C, prior to step D and after the seal according to step B).

12. The method according to any one of claims 1 to 3, characterized in that, The method includes the following steps: A) The anodizing step is performed under the following conditions: during the anodizing step, the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C, and a DC voltage is applied to the immersed component according to a voltage curve comprising a voltage rising at a rate of less than 1 V / min until a voltage value known as a plateau value between 5 V and 13 V is reached; B) The step of sealing the anode layer formed on the component at the end of step A), wherein the sealing is performed under the conditions described in claim 1; and D) A fiber laser marking step, wherein the fiber laser marking step has one or more features described in claim 1.

13. The method according to any one of claims 1 to 3, characterized in that, The method includes the following steps: A) The anodizing step is performed under the following conditions: during the anodizing step, the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C, and a DC voltage is applied to the immersed component according to a voltage curve comprising a voltage rising at a rate of less than 1 V / min until a voltage value known as a plateau value between 5 V and 13 V is reached; A1) The step of immersing the component, wherein step A1-1) and then step A1-2) are performed under the conditions described below; - Step A1-1): A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O, and CrK(SO4)2·xH2O; then - Step A1-2): A water bath containing an oxidizing compound, wherein the oxidizing compound is selected from the group consisting of hydrogen peroxide, ammonium fluoride, potassium fluorozirconate, potassium permanganate and sodium permanganate; B) The step of sealing the anode layer formed on the component at the end of step A), wherein the sealing is performed under the conditions described in claim 1; and D) A fiber laser marking step, wherein the fiber laser marking step has one or more features described in claim 1.

14. The method according to any one of claims 1 to 3, characterized in that, The method includes the following steps: A) The anodizing step is performed under the following conditions: during the anodizing step, the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C, and a DC voltage is applied to the immersed component according to a voltage curve comprising a voltage rising at a rate of less than 1 V / min until a voltage value known as a plateau value between 5 V and 13 V is reached; A1) The step of immersing the component, wherein step A1-1) and then step A1-2) are performed under the conditions described below; - Step A1-1): A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O, and CrK(SO4)2·xH2O; then - Step A1-2): A water bath containing an oxidizing compound, wherein the oxidizing compound is selected from the group consisting of hydrogen peroxide, ammonium fluoride, potassium fluorozirconate, potassium permanganate, and sodium permanganate; B) The step of sealing the anode layer formed on the component at the end of step A), wherein the sealing is performed under the conditions described in claim 1; C) Final hydrothermal sealing is performed in deionized water with a resistivity equal to or greater than 0.01 MOhms at a temperature greater than 96°C; and D) A fiber laser marking step, wherein the fiber laser marking step has one or more features described in claim 1.

15. The method according to any one of claims 1 to 3, characterized in that, The method includes the following steps: A) The anodizing step is performed under the following conditions: during the anodizing step, the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C, and a DC voltage is applied to the immersed component according to a voltage curve comprising a voltage rising at a rate of less than 1 V / min until a voltage value known as a plateau value between 5 V and 13 V is reached; A1) The step of immersing the component, wherein step A1-1) is carried out in a water bath containing a trivalent chromium salt selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O and CrK(SO4)2·xH2O; B) The step of sealing the anode layer formed on the component at the end of step A), wherein the sealing is performed under the conditions described in claim 1; and D) A fiber laser marking step, wherein the fiber laser marking step has one or more features described in claim 1.

16. The method according to any one of claims 1 to 3, characterized in that, The method includes the following steps: A) The anodizing step is performed under the following conditions: during the anodizing step, the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C, and a DC voltage is applied to the immersed component according to a voltage curve comprising a voltage rising at a rate of less than 1 V / min until a voltage value known as a plateau value between 5 V and 13 V is reached; Im) is the step of immersing the component in an organic or inorganic dye bath at the end of step A) and anodizing it; B) The step of sealing the anode layer formed on the component at the end of step A), wherein the sealing is performed under the conditions described in claim 1; and D) A fiber laser marking step, wherein the fiber laser marking step has one or more features described in claim 1.

17. The method according to any one of claims 1 to 3, characterized in that, The method includes the following steps: A) The anodizing step is performed under the following conditions: during the anodizing step, the component is immersed in a water bath comprising sulfuric acid with a concentration between 150 g / L and 250 g / L and a temperature between 14°C and 21°C, and a DC voltage is applied to the immersed component according to a voltage curve comprising a voltage rising at a rate of less than 1 V / min until a voltage value known as a plateau value between 5 V and 13 V is reached; Im) is the step of immersing the component, which has been anodized at the end of step A), in an organic or inorganic dye bath; then A1) The step of immersing the component, wherein step A1-1) and then step A1-2) are performed under the conditions described below; - Step A1-1): A water bath containing trivalent chromium salts, wherein the trivalent chromium salts are selected from the group consisting of CrF3·xH2O, CrCl3·xH2O, Cr(NO3)3·xH2O, (CH3CO2)2Cr·xH2O, (CH3CO2)7Cr3(OH)2·xH2O, Cr2(SO4)3·xH2O, and CrK(SO4)2·xH2O; then - Step A1-2): A water bath containing an oxidizing compound, wherein the oxidizing compound is selected from the group consisting of hydrogen peroxide, ammonium fluoride, potassium fluorozirconate, potassium permanganate and sodium permanganate; B) The step of sealing the anode layer formed on the component at the end of step A), wherein the sealing is performed under the conditions described in claim 1; and D) A fiber laser marking step, wherein the fiber laser marking step has one or more features described in claim 1.

18. The use of the method according to any one of claims 1 to 17 for manufacturing or marking aluminum or aluminum alloy parts for use in the aerospace, automotive, railway, watchmaking, medical, nuclear and petroleum industries.

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