METHODS FOR TREATING METALLIC SUBSTRATES AND ARTICLES COMPRISING A FUNCTIONALIZED PHOSPHONATE LAYER

Abstract

Methods for treating metallic substrates and articles comprising a phosphonate functionalized layer are provided. The method comprises contacting a metallic substrate comprising at least one aluminum and one aluminum alloy with a fluid to form a phosphonate functionalized layer on at least one region of the metallic substrate. The fluid comprises at least one phosphonate-containing acid and one derivative thereof. At least one of the phosphonate-containing acid and the derivative thereof comprises a pKa of a first acidic proton. The fluid comprises a pH value at least 0.5 greater than the pKa of the first acidic proton. The article comprises a metallic substrate comprising aluminum or an aluminum alloy and a phosphonate functionalized layer on at least one region of the metallic substrate.

Description

METHODS FOR TREATING METALLIC SUBSTRATES AND ARTICLES COMPRISING A FUNCTIONALIZED PHOSPHONATE LAYER TECHNICAL FIELD OF THE INVENTION This description refers to methods for treating metallic substrates and articles comprising a functionalized phosphonate layer. BACKGROUND OF THE INVENTION Metallic substrates can undergo various surface treatments. These treatments can impart different properties to the surface of metallic substrates. Designing a durable and aesthetically pleasing surface treatment presents challenges. SUMMARY OF THE INVENTION In one aspect, a method for treating a metallic substrate is provided. The method comprises contacting a metallic substrate comprising at least one aluminum and one aluminum alloy with a fluid to form a phosphonate-functionalized layer on at least one region of the metallic substrate. The fluid comprises at least one phosphonate-containing acid and a derivative thereof. The at least one of the phosphonate-containing acids and the derivative thereof comprises a pKa of a first acid proton. The fluid comprises a pH value at least 0.5 greater than the pKa of the first acid proton. In another aspect, an article is provided. The article comprises a metallic substrate comprising aluminum or an aluminum alloy and a functionalized phosphonate layer on at least one region of the metallic substrate. It is understood that the inventions described and disclosed herein are not limited to the aspects summarized in this Summary. The reader will appreciate the foregoing details, as well as others, when considering the following detailed description of various non-limiting and non-exhaustive aspects in accordance with this description. BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the examples, and how to achieve them, will become clearer, and the examples will be better understood, with reference to the following description taken in conjunction with the accompanying drawings, where: Figure 1 is a flow diagram illustrating a non-limiting modality of a metallic substrate coating process according to the present description; Figure 2 is a schematic diagram of a non-limiting embodiment of an article comprising a metallic substrate and a phosphonate functionalized layer on at least one region of the metallic substrate according to the present description; Figure 3 provides images illustrating portions of the AD Samples after exposure to thermal shock; Figure 4A is a modified image illustrating Samples N and O after the CASS test; and Figure 4B is a modified image of Figure 4A that selectively illustrates the holes formed in Samples N and O. The corresponding reference characters indicate corresponding parts in the different views. The illustrations provided in this description depict specific embodiments and shall not be construed as limiting the scope of the appended claims in any way. DETAILED DESCRIPTION OF THE INVENTION This description describes and illustrates various examples to provide a general understanding of the structure, function, and use of the articles and methods described. The various examples described and illustrated herein are non-limiting and non-exhaustive. Therefore, an invention is not limited by the description of the various non-limiting and non-exhaustive examples described herein. Rather, the invention is defined solely by the claims. The elements and features illustrated and / or described in connection with different examples may be combined with the elements and features of other examples. Such modifications and variations are intended to be included within the scope of this description.As such, the claims may be amended to list any element or feature that is expressly or inherently described, or otherwise expressly or inherently supported, in this description. Furthermore, the Applicant reserves the right to amend the claims to affirmatively disclaim elements or features that may be present in the prior art. The various embodiments described and disclosed in this description may comprise, consist of, or substantially consist of the elements and features, as variously described herein. Any reference in this description to different modalities, some modalities, a modality, a modality, or similar expressions means that a particular element, structure, or feature described in relation to the example is included in at least one modality. Therefore, the presence of phrases such as "in various modalities," "in some modalities," "in a modality," "in a modality," or similar phrases in this description does not necessarily refer to the same modality. Furthermore, the particular elements, structures, or features described may be combined in any appropriate way in one or more modalities. Therefore, the particular elements, structures, or features illustrated or described in relation to one modality may be combined, in whole or in part, with the elements, structures, or features of one or more additional modalities without limitation.It is intended that these modifications and variations be included within the scope of these modalities. In this description, unless otherwise stated, all numerical parameters shall be understood as preceded and modified, in all cases, by the term "around," where the numerical parameters possess the characteristic of inherent variability of the underlying measurement techniques used to determine the numerical value of the parameter. At least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter described herein shall be interpreted at least by virtue of the number of significant digits reported and by applying common rounding techniques. Furthermore, any numerical interval mentioned in this description includes all subintervals contained within that interval. For example, an interval from 1 to 10 includes all subintervals between (and including) the mentioned minimum value of 1 and the mentioned maximum value of 10; that is, any subinterval with a minimum value greater than or equal to 1 and a maximum value less than or equal to 10. Any maximum numerical limitation mentioned in this description is intended to include all lower numerical limitations contained therein, and any The minimum numerical limitation mentioned in this description includes all larger numerical limitations included therein. Accordingly, the Applicant reserves the right to amend this description, including the claims, to expressly mention any sub-intervals included within the expressly mentioned intervals. All such intervals are inherently described in this description. The grammatical articles *un*, *una*, and *el / la*, as used herein, are intended to include at least one or one or more, unless otherwise indicated, even if *at least one* or *one or more* is expressly used in certain cases. Therefore, the above grammatical articles are used in this description to refer to one or more of one (i.e., at least one) of the identified items. Furthermore, the use of a singular noun includes the plural, and the use of a plural noun includes the singular, unless the context of use otherwise requires it. As used herein, the term phosphonate refers to phosphorus compounds comprising one phosphorus atom coordinated with three oxygen atoms. One of the three oxygen atoms may be coordinated to the phosphorus atom by a double bond. A phosphonate does not comprise phosphoric acid (H3O4P). For example, a phosphonate may comprise the general formula (I), wherein Ri, R2, and R3 are individually selected from hydrogen, an alkyl, or an aryl group. As such, Ri, R2, and R3 may be the same or different groups. Formula (I) O R1O-P-R3 or2 The selection of a surface treatment may require, for example, a balance between desired adhesion, corrosion protection, and aesthetic properties. According to this description, a method for treating a metallic substrate is provided that can promote the adhesion of a top layer to a metallic substrate, provided it also provides corrosion protection and a desired aesthetic appearance. Additionally, this description provides articles comprising a functionalized phosphonate layer. Articles incorporating this functionalized phosphonate layer may exhibit superior adhesion, enhanced corrosion resistance, increased abrasion resistance, and / or a desirable aesthetic appearance. A method for treating a metallic substrate according to the present description comprises contacting a metallic substrate with a fluid comprising a composition capable of forming a phosphonate-functionalized layer on at least one region of the metallic substrate. Contacting the metallic substrate may comprise at least one of immersing the metallic substrate in a bath of the fluid, spraying the fluid onto the metallic substrate, and wiping the metallic substrate with the fluid. In certain embodiments where contacting the metallic substrate comprises immersing the metallic substrate in a fluid bath, the fluid bath may be agitated. For example, the fluid bath may be agitated by at least one method selected from the group consisting of bubbling gas through the fluid in the bath and agitating the fluid (e.g., circulating the fluid with a pump, agitating the fluid with an impeller). In various embodiments of the method, the fluid may come into contact with the metallic substrate for at least 1 second, such as, for example, at least 5 seconds, at least 10 seconds, at least 30 seconds, at least 1 minute, at least 5 minutes, at least 10 minutes, at least 20 minutes, or at least 30 minutes. The fluid may come into contact with the metallic substrate for no more than 40 minutes, such as, for example, no more than 30 minutes, no more than 20 minutes, no more than 10 minutes, no more than 5 minutes, no more than 1 minute, no more than 30 seconds, no more than 10 seconds, or no more than 5 seconds. In a certain embodiment of the method, the fluid may come into contact with the metallic substrate for a period ranging from 1 second to 40 minutes, such as, for example, 2 seconds to 10 minutes, 5 seconds to 10 minutes, 5 seconds to 5 minutes, 5 seconds to 2 minutes, or 10 seconds to 30 seconds. The fluid may react with the metallic substrate during the contact time.The fluid may comprise at least one of a phosphonate-containing acid and a derivative thereof. For example, in certain embodiments, the phosphonate-containing acid may be at least one of phosphorous acid (H3O3P), phenylphosphonic acid (CeHvOaP), ethylphosphonic acid (C2H7O3P), octylphosphonic acid (C8H19O3P), octadecylphosphonic acid (C18H39O3P), vinylphosphonic acid (C2H5O3P), vinylphosphonic acid dimethyl ester (C4H10O3P), diethylenetriaminepentakis(methylphosphonic acid) (CH5O3P), octanediphosphonic acid (CgH2oOeP2), and derivatives of any of these compounds. A derivative of a phosphonic acid can be, for example, a deprotonated phosphonic acid (for example, a deprotonated derivative thereof, a conjugate base) and / or a phosphonic acid that is at least twice protonated.For example, the phosphonic acid derivative may comprise at least one of a deprotonated phosphorous acid (H2O3PJ), a deprotonated phenylphosphonic acid (CeHgOgPJ), a deprotonated ethylphosphonic acid (CgHgOgP-), a deprotonated octylphosphonic acid (CgHgOaP-), a deprotonated octadecylphosphonic acid (CigHggOgP-), a deprotonated vinylphosphonic acid (C2H4O3PJ), a dimethyl ester of deprotonated vinylphosphonic acid (C^gOgP-), a diethylenetriaminopentakis (methylphosphonic acid) (CHsOgP-), and a deprotonated octane diphosphonic acid (C8H19O6P2J). The phosphonate-containing acid and / or its derivative may comprise a pKa (e.g., -log of the acid dissociation constant, Ka) of a first acid proton. The pKa of the first acid proton corresponds to a pH at which substantially equal concentrations of the phosphonate-containing acid and its corresponding conjugate base (e.g., deprotonated phosphonate-containing acid) are present in solution. Increasing the pH of a solution comprising the phosphonate-containing acid and / or its derivative above the pKa of the first acid proton may increase the concentration of the conjugate base and decrease the concentration of the phosphonate-containing acid. Decreasing the pH of the solution comprising the phosphonate-containing acid and / or its derivative below the pKa of the first acid proton may decrease the concentration of the conjugate base and increase the concentration of the phosphonate-containing acid.The conjugate base may comprise a negative charge (-1). The acid containing phosphonate may comprise a neutral charge. In various embodiments, the phosphonate-containing acid and / or its derivative may comprise at least two pKa values, such as, for example, a pKa value for a first acidic proton and a pKa value for a second acidic proton. The pKa value for the second acidic proton corresponds to a pH at which substantially equal concentrations of the conjugate base and a corresponding secondary conjugate base (e.g., a twice-deprotonated conjugate base) are present in solution. The secondary conjugate base may have a negative charge of two (-2). In various examples, the phosphonate-containing acid and / or its derivative may comprise at least three pKa values. In various embodiments where the phosphonate-containing acid and / or its derivative comprises phosphorous acid, the pKa value for the first acidic proton may be 1.3 and the pKa value for the second acidic proton may be 6.7.In various embodiments where the phosphonate-containing acid and / or its derivative comprises ethylphosphonic acid, the pKa of the first acid proton can be 2.4 and the pKa of the second acid proton can be 8.1. In various embodiments where the phosphonate-containing acid and / or its derivative comprises phenylphosphonic acid, the pKa of the first acid proton can be 1.8 and the pKa of the second acid proton can be 7.1. In various embodiments where the phosphonate-containing acid and / or its derivative comprises vinylphosphonic acid, the pKa of the first acid proton can be 2.6 and the pKa of the second acid proton can be 7.3. The pH of the fluid used in this method may be selected based on the desired reactivity of the phosphonate-containing acid and / or its derivative. The pH of the fluid may be selected to reduce the solubility of the metal substrate in the fluid and thereby extend the operating life of the fluid. In various embodiments, the fluid may have a pH value at least 0.5 greater than the pKa of the first acid proton, such as, for example, at least 1 pH value greater, at least 2 pH values ​​greater, at least 3 pH values ​​greater, at least 4 pH values ​​greater, at least 5 pH values ​​greater, at least 6 pH values ​​greater, or at least 8 pH values ​​greater than the pKa of the first acid proton. In certain embodiments, the fluid may have a pH no greater than 10 pH values ​​greater than the pKa of the first acid proton, such as, for example, no greater than 8 pH values ​​greater, no greater than 6 pH values ​​greater, no greater than 5 IVIA / a / ZUZ I / uuu» / z pH values ​​greater than, not greater than 4 pH values ​​greater than, not greater than 3 pH values ​​greater than, not greater than 2 pH values ​​greater than, not greater than 1 pH value greater than, or not greater than 0.5 pH values ​​greater than the pKa of the first acid proton. In certain embodiments according to the present description, the fluid may comprise a pH in the range of the pKa of the first acid proton to 10 pH values ​​greater than the pKa of the first acid proton, such as, for example, at least 0.5 pH values ​​greater than the pKa of the first acid proton to 8 pH values ​​greater than the pKa of the first acid proton or at least 4 pH values ​​greater than the pKa of the first acid proton to 6 pH values ​​greater than the first acid proton. In some embodiments, the fluid may comprise a pH in the range of the pKa of the first acid proton to the pKa of the second acid proton.In various forms, the fluid comprises a pH where the phosphonate-containing acid is substantially dissociated into the conjugate base. In certain formulations, the fluid may have a pH greater than 1, such as, for example, greater than 1.5, greater than 2, greater than 2.5, greater than 3, greater than 4, greater than 5, greater than 5.5, greater than 6, greater than 6.5, greater than 7, greater than 8, greater than 8.5, greater than 9, or greater than 10. For example, the fluid may have a pH no greater than 12, such as, no greater than 11, no greater than 10, no greater than 9, no greater than 8.5, no greater than 8, no greater than 7, no greater than MA / a / ZUZI / uuu» / z 6.5, not greater than 6, not greater than 5.5, not greater than 5, not greater than 4, not greater than 3, not greater than 2.5 or not greater than 2. In various forms, the fluid may comprise a pH in a range of 1 to 12, such as, for example, 1.5 to 10, 1.5 to 9, 2.5 to 8, 4 to 10, 6 to 10, 4 to 8, 6 to 8, 5.5 to 8.5 or 6.5 to 8.5. In certain embodiments, the fluid used in this method may be an aqueous liquid solution. For example, the fluid may comprise a phosphonate-containing acid and / or a derivative thereof with an equilibrium of water and, optionally, buffers, stabilizers, surfactants, and / or other additives. In some embodiments, the fluid may comprise at least 0.1 percent by weight of the phosphonate-containing acid and / or derivative thereof, based on the total weight of the fluid, such as, for example, at least 0.5 percent by weight, at least 1 percent by weight, at least 2 percent by weight, at least 5 percent by weight, at least 10 percent by weight, or at least 15 percent by weight of the phosphonate-containing acid and / or derivative thereof based on the total weight of the fluid. In various embodiments, the fluid comprises no more than 20 percent by weight of the phosphonate-containing acid and / or derivative thereof based on the total weight of the fluid, such as, for example, no more than 15 percent by weight, no more than 10 percent by weight, no more than 5 percent by weight, no more than 2 percent by weight, no more than 1 percent by weight, or no more than 0.5 percent by weight of the phosphonate-containing acid and / or derivative thereof based on the total weight of the fluid. In certain embodiments, the fluid comprises 0.1 percent by weight to 20 percent by weight of the phosphonate-containing acid and / or derivative thereof based on the total weight of the fluid, such as, for example, 0.2 percent by weight to 10 percent by weight, 0.5 percent by weight to 10 percent by weight, 0.2 percent by weight to 5 percent by weight, or 0.5 percent by weight to 2 percent by weight of the phosphonate-containing acid and / or derivative thereof based on the total weight of the fluid. Contacting the metallic substrate with the fluid can form a functionalized phosphonate layer on the substrate. For example, the oxide (e.g., aluminum oxide when the substrate includes aluminum or an aluminum alloy) present on a surface of the metallic substrate can be modified by the phosphonate-containing acid in the fluid, forming a functionalized phosphonate layer in at least one region of the substrate. The functionalized phosphonate layer may comprise a phosphonate group bonded to the metallic substrate. In various embodiments, the phosphonate group is bonded to the metallic substrate via a PO-Al bond. In other embodiments, the phosphonate group may be bonded to an oxide group on the metallic substrate or directly to a metal atom. The functionalized phosphonate layer can improve the corrosion resistance of the metallic substrate and enhance the adhesion of a coating to the substrate. In various configurations, the functionalized phosphonate layer does not affect, or only minimally affects, the aesthetics of the metallic substrate. For example, it can minimize the difference in CIELAB (International Commission on Illumination L*a*b*) color space brightness (AL*) between the metallic substrate without the functionalized phosphonate layer (e.g., before contact with the fluid) and the metallic substrate with the functionalized phosphonate layer (e.g., after contact with the fluid). In various configurations, the CIELAB (AL*) brightness difference between the metallic substrate with the functionalized phosphonate layer and the metallic substrate without the functionalized phosphonate layer is no greater than 10, such as, for example, no greater than 8, no greater than 5, no greater than 3, no greater than 2, no greater than 1, or no greater than 0.5, as measured with a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer.In certain embodiments, the CIELAB lightness difference (AL*) between the metal substrate comprising the phosphonate functionalized layer and the metal substrate without the phosphonate functionalized layer is greater than 0.1, greater than 0.5, or greater than 1, as measured with a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer. In some embodiments, the CIELAB lightness difference (AL*) between the metal substrate comprising the phosphonate functionalized layer and the metal substrate without the functionalized layer is greater than 0.1, greater than 0.5, or greater than 1, as measured with a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer. The phosphonate luminosity difference is 0. In certain modalities, a CIELAB (AL*) luminosity difference between the metallic substrate comprising the phosphonate functionalized layer and the metallic substrate without the phosphonate functionalized layer is in the range of 0 to 10, such as, for example, 0 to 5, 0 to 3, 0 to 2, or 0.1 to 2, measured with a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer. In certain embodiments described herein, the method for treating the metallic substrate according to this description may be incorporated into a metallic substrate coating process as shown schematically in, for example, Figure 1. The metallic substrate coating process may comprise cleaning the metallic substrate, 102. For example, in certain embodiments, the metallic substrate may be cleaned using at least one alkaline cleaning technique, acid cleaning, and carbon dioxide-based cleaning. In various embodiments, the metallic substrate may be rinsed to remove residual chemicals used during cleaning, 104. The rinsing may comprise, for example, spraying the metallic substrate with a solution comprising water. In various embodiments, the metallic substrate may be polished before cleaning. The metallic substrate may be subjected to the metallic substrate treatment method described herein. For example, the metallic substrate may be contacted with a fluid having a composition capable of forming a phosphonate functionalized layer on at least one region of the metallic substrate, 106. The cleaning step 104 may occur before the contact step 106. The metallic substrate may be rinsed to remove the residual fluid 108. The rinsing may comprise, for example, spraying the metallic substrate with water or a solution comprising water. In various embodiments, the metallic substrate may be dried. In the embodiment illustrated in Figure 1, a coating composition can be deposited onto the phosphonate-functionalized layer on the metallic substrate, 110. The coating composition can be deposited by, for example, at least one of the following methods: spray coating, rotary coating, dip coating, roller coating, flow coating, and film coating. The coating composition can be deposited in contact with the phosphonate-functionalized layer. As used herein, particularly in relation to coating layers or films, the terms on, over, above, and variants thereof (e.g., applied to, formed on, deposited on, provided on, located on, and the like) mean applied, formed, deposited, provided, or otherwise located on a substrate surface but not necessarily in contact with the substrate surface. For example, a coating layer applied to a substrate does not preclude the presence of one or more coating layers of the same or different composition situated between the applied coating layer and the substrate. Similarly, for example, a second coating layer applied over a first coating layer does not preclude the presence of one or more coating layers of the same or different composition situated between the second applied coating layer and the first applied coating layer. After deposition of the coating composition, the coating composition can be cured to form coating 112 on the metallic substrate. As used herein, the terms cured and curing refer to a chemical crosslinking of components in a curable composition and / or a chain extension of the curable composition. Accordingly, the terms cured and curing do not encompass solely the physical drying of curable compositions by evaporation of the solvent or carrier. In this respect, the term cured, as used in this description, refers to the state of a curable composition in which a component of the curable composition has chemically reacted to form a new covalent bond. For example, the curing of the coating composition may comprise at least one of the following: ambient curing, airflow, ultraviolet radiation, electron beam radiation, gamma radiation, heat, and oxygen. In various embodiments, the curing of the coating composition may comprise solvent evaporation within the coating composition. In various embodiments, the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane. The coating may be substantially transparent or opaque. As used herein, the term substantially transparent refers to a coating that produces no or minimal scattering or diffuse reflection of visible electromagnetic radiation. In certain embodiments, the coating may be colorless. In various embodiments, the coating may include a colorant, such as a pigment or dye. In various embodiments, the coating may protect the article from, for example, abrasion and / or corrosion. Figure 2 illustrates an article 200 comprising a metallic substrate 202 and a phosphonate functionalized layer 204 in at least one region of the metallic substrate 202. The layer MA / a / ZUZI / uuu» / The phosphonate-functionalized layer 204 can be in contact with and bonded to the metallic substrate 202. A coating 206 can be deposited on at least a region of the phosphonate-functionalized layer 204. The phosphonate-functionalized layer 204 can be bonded to and in contact with the coating 206. The phosphonate-functionalized layer 204 can promote adhesion between the coating 206 and the metallic substrate 202. In certain embodiments, the metallic substrate and the article comprising the substrate may comprise at least one aluminum and one aluminum alloy. For example, the aluminum alloy may comprise at least one of the following: an aluminum alloy of the 1000 series, an aluminum alloy of the 2000 series, an aluminum alloy of the 3000 series, an aluminum alloy of the 4000 series, an aluminum alloy of the 5000 series, an aluminum alloy of the 6000 series, and an aluminum alloy of the 7000 series. In various examples, the aluminum alloy may comprise an aluminum alloy 6061 and / or an aluminum alloy 6361. In various embodiments, the aluminum alloy may comprise a zinc-enriched aluminum alloy of the 5000 series. In various embodiments, the aluminum alloy may comprise A356 and / or A357.An article comprising a metallic substrate with a phosphonate-functionalized layer can be used in a variety of product applications, such as commercial end uses in industrial applications, consumer applications (e.g., consumer electronics and / or household appliances), or other areas. For example, an article comprising a metallic substrate with a phosphonate-functionalized layer can be used in at least one of the following fields: aerospace (e.g., an aerospace component), automotive (e.g., an automotive component), transportation (e.g., a transportation component), or building and construction (e.g., a building component or a construction component).In certain embodiments, the article including the metallic substrate comprising a functionalized phosphonate layer can be configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component. In various embodiments, an article including a metallic substrate comprising a phosphonate-functionalized layer can be used in an elevated-temperature application, such as in an aerospace or automotive vehicle. In certain embodiments, an article including a metallic substrate comprising a phosphonate-functionalized layer can be used as an engine component in an aerospace vehicle (for example, in a blade form, such as a compressor blade incorporated in the engine). In other embodiments, an article including the metallic substrate comprising a phosphonate-functionalized layer can be used as a heat exchanger component in the engine of an aerospace vehicle. The aerospace vehicle incorporating the engine / heat exchanger component can then be operated.In certain embodiments, an article including a metallic substrate comprising a phosphonate functionalized layer may be an automotive engine component. The motor vehicle including such an automotive component (e.g., an engine component) may subsequently be operated. For example, an article including a metallic substrate comprising a phosphonate functionalized layer may be used as a turbocharger component (e.g., a compressor wheel of a turbocharger, where elevated temperatures may occur when recirculating engine exhaust gases back through the turbocharger), and a motor vehicle including the turbocharger component may be operated.In another embodiment, an article including a metallic substrate comprising a phosphonate-functionalized layer can be used as a blade in a land-based (stationary) turbine for generating electricity, and the land-based turbine, including the metallic part, can be operated to generate electricity. In certain embodiments, an article including a metallic substrate comprising a functionalized layer of... ΙνΙΛ / α / ZυΖΊ / UUU» / Z phosphonate can be used in defense applications, such as in bulletproof vests or armored vehicles (e.g., armor plating). In other embodiments, an article comprising a metallic substrate comprising a functionalized phosphonate layer can be used in consumer electronics applications, such as, for example, in laptop casings, battery cases, cell phones, cameras, portable music players, wearable devices, computers, televisions, microwaves, kitchen utensils, washing machines / dryers, refrigerators, or sporting goods. In certain embodiments, an article comprising a metallic substrate with a functionalized phosphonate layer can be used in a structural application, such as an aerospace or automotive structural application. For example, an article comprising a metallic substrate with a functionalized phosphonate layer can be formed into various aerospace structural components, including, for example, floor beams, seat rails, fuselage frames, bulkheads, stringers, ribs, spars, and supports. In various embodiments, an article comprising a metallic substrate with a functionalized phosphonate layer can be used in an automotive structural application.For example, an article comprising a metallic substrate with a functionalized phosphonate layer can be formed into various automotive structural components, including, for example, space frame nodes, crash towers, and subframes. In one embodiment, an article comprising a metallic substrate with a functionalized phosphonate layer can be a blank automotive body product. In another aspect, an article comprising a metallic substrate with a phosphonate-functionalized layer can be used in industrial engineering applications. For example, such an article can be formed into various industrial engineering products, such as tread plates, toolboxes, bolting platforms, bridge decks, and ramps. In various configurations, the metallic substrate can be a vehicle wheel or a part of a vehicle wheel. The vehicle wheel can be at least one of, for example, a bonded wheel, a welded wheel, a formed wheel (e.g., vacuum-formed), a cured wheel, a cast wheel, a forged wheel, or an additively manufactured wheel. The vehicle wheel may undergo further processing to produce the final vehicle wheel, such as machining or polishing. MA / a / ZUZI / UUUU / z Examples AS Samples comprising a 6000 series aluminum alloy metallic substrate were prepared and polished. The AS Samples were contacted with a phosphorous acid solution (e.g., a fluid comprising a phosphonate-containing acid and / or a derivative thereof) to produce a functionalized phosphonate layer on them. The phosphorous acid solution comprised a concentration ranging from 0.5 wt% to 2 wt% phosphorous acid (available as a 98% extra-pure powder from Thermo Fisher Scientific, Waltham, Massachusetts) in water equilibrium. Samples A and B were exposed to a 0.6 wt% phosphorous acid solution at pH 1.5 for 1 and 3 minutes, respectively. Samples C and D were exposed to a 0.6 wt% solution at pH 6.5 for 1 and 3 minutes, respectively. Subsequently, Samples A and B were coated with a siloxane coating and tested for adhesion. Adhesion performance was tested by scoring the coating in an X pattern onto the metal substrate with a blade to expose the underlying metal. The adhesion of the coating to the metal substrate was evaluated by thermal shock according to GM 9525P, whereby the samples were subjected to a single soak / freeze / thaw (steam exposure) cycle in water. Figure 3 shows a portion of each Sample A and B, including the X-shaped score after thermal shock exposure.Sample A showed significant loss of adhesion, as evidenced by the missing coating around the center of the X-shaped mark. Sample B also showed a loss of adhesion, as evidenced by a chip in the coating proximal to the rightmost section of the X-shaped mark. No loss of adhesion was observed for Samples C and D. Therefore, Samples C and D exhibited improved coating adhesion compared to Samples A and B. It is believed that other methods of pretreating metallic substrates according to the description herein may also achieve improved adhesion performance. The EM samples were contacted with either a 0.5 wt% phosphorous acid solution or a 2 wt% phosphorous acid solution. Subsequently, the EM samples were coated with a siloxane coating. The corrosion resistance of the EM samples was tested for the formation of thread marks. The thread mark formation test was performed by scoring a 1.5-inch-long line through the coating with a knife to expose the underlying metallic substrate. The EM samples were MA / a / ZUZI / uuu» / z were then exposed to the copper-accelerated acetic acid salt spray (CSS) test in accordance with ASTM B368-09 (2014). After the CASS test, the length of the longest filiform trace (i.e., filament-like corrosion originating from the trace) of each EM Sample was measured under a microscope using a ruler. The corrosion behavior of each EM Sample was repeated two more times for a total of 3 measurements for each EM Sample. The average of the longest filiform trace length from the 3 measurements for each EM Sample is shown in Table 1. Table 1: Sample Weight percentage of phosphonic acid (based on total fluid weight) Fluid pH Fluid-sample contact time (seconds) Length of longest filiform footprint (average of 3 samples, mm) E 0.5 1.5 10 1.57 F 0.5 1.5 30 1.4 G 0.5 6.5 10 1.17 H 0.5 6.5 30 0.87 I 0.5 8.5 10 0.77 J 2 1.5 10 1.23 K 2 1.5 30 1.3 L 2 6.5 10 0.97 M 2 8.5 30 0.97 Sample G showed better filiform corrosion behavior compared to sample E (25% less than the average filiform indentation length). Sample H showed better filiform corrosion behavior compared to sample F (38% less than the average filiform indentation length). Sample I showed better filiform corrosion behavior compared to sample E (51% less than the average filiform indentation length). Sample L showed better filiform corrosion behavior compared to sample J (21% less than the average filiform indentation length). Sample M showed better filiform corrosion behavior compared to sample K (25% less than the average filiform indentation length).It is believed that other methods of pretreating metallic substrates according to the present description can also achieve an improvement in filiform corrosion behavior. Samples N and O were substantially equal in size. Samples N and O were prepared in duplicate. Sample N was contacted with a 0.6 percent wt phosphorous acid solution comprising a pH of 1.5, and Sample O was contacted with a 0.6 percent wt phosphorous acid solution comprising a pH of 6.5. After coating Samples N and O with a siloxane coating, Samples N and O were subjected to a CASS Test in accordance with ASTM B368-09 (2014). Field corrosion (corrosion away from the trace) on Samples N and O after the CASS test was measured using image analysis. For image analysis, an image of each Sample N and O was captured and modified according to similar parameters to emphasize the pits on each sample. These images are shown in Figure 4A. The images shown in Figure 4A were then further modified to selectively enhance field corrosion, and these additional modified images are shown in Figure 4B. Field corrosion on each of the samples shown in Figure 4B was measured by counting the pits on a sample and also by measuring the total surface area occupied by all the pits on the sample. Sample N had an average of 63 pits and an average total pit surface area of ​​205 mm².Sample O had an average of 19 pits, representing a 70% improvement (based on the number of pits) compared to Sample N. Sample O had an average total pit surface area of ​​35.5 mm², which is an 83% improvement compared to Sample N. It is believed that other methods of pretreating metallic substrates according to the present description may also achieve an improvement in field corrosion. MA / a / ZUZI / uuu» / z The L* value of each PS Sample was measured using a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer in the polished state. These L* values ​​are referred to as L*i in this description. The PS Samples were then alkali-cleaned, and the L* value of each sample (L*2) was measured using the BYK-Gardner Spectro Guide 45 / 0 spectrophotometer after alkaline cleaning. Samples PQ were contacted with a 0.6 wt% phosphorous acid solution. Samples P and R were contacted with a solution at pH 1.5, while Samples Q and S were contacted with a phosphorous acid solution at pH 6.5. Samples P and Q were contacted with their respective phosphorous acid solutions for 1 minute, and Samples R and S were contacted with their respective phosphorous acid solutions for 3 minutes. The L* value of each Sample PS (L*a) was measured using a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer after contacting the Sample PS with the phosphorous acid solutions. After coating each of the PS Samples with a siloxane coating, the L* value of each PS Sample was measured using a BYK-Gardner Spectro Guide 4 5 / 0 spectrophotometer (L*4). The various L* values ​​measured for the Samples PS are provided in Table 2. Table 2 also lists a value of AL*' = | L*3- L*i | , as well as a value of AL* ' ' = | L*4- L*i I . Table 2 Sample L*i L*2 L*3 AL*' (|L *3L*i|) L*4 AL* (|L*4- L*i|) P 18.4 19.2 29.4 11 32 13.6 Q 19.6 20.6 19.5 0.1 22.4 1.8 R 18.6 19.7 43.3 24.7 46.3 27.7 S 19.6 20.6 19.5 0.1 22.4 2.8 The AL*' value measured for Sample Q was an improvement over the AL*' value for Sample P. Specifically, the AL*' value for Sample Q is 99% lower than that of Sample P. The AL*' value measured for Sample S was also an improvement over the AL*' value for Sample R. Specifically, the AL*' value for Sample S is 99% lower than that of Sample R. It is believed that other methods of pretreating metallic substrates according to the present description may also achieve an improvement in AL*' and / or AL*''. ASPECTS OF THE INVENTION Various aspects of the invention include, but are not limited to, the aspects listed in the following numbered provisions. 1. A method for treating a metallic substrate comprising: contacting a metallic substrate comprising at least one aluminum and an aluminum alloy with a fluid to form a phosphonate functionalized layer on at least one region of the metallic substrate, the fluid comprising at least one of a phosphonate-containing acid and a derivative thereof, wherein at least one of the phosphonate-containing acid and the derivative thereof comprises a pKa of a first acid proton, and wherein the fluid comprises a pH at least 0.5 times greater than the pKa of the first acid proton. 2. The method of clause 1, wherein the fluid comprises a pH at least 2 pH values ​​greater than the pKa of the first acid proton. 3. The method of any of clauses 1-2, wherein the fluid comprises a pH of 11 or less. 4. The method of any of clauses 1-3, wherein the fluid comprises a pH in a range of 3.5 to 9.5. 5. The method of any of clauses 1-4, wherein the fluid comprises a pH in a range of 6.5 to 8.5. 6. The method of any of clauses 1-5, wherein the phosphonate-containing acid is at least one of phosphorous acid, phenylphosphonic acid, ethylphosphonic acid, octylphosphonic acid, octadecylphosphonic acid, vinylphosphonic acid, vinylphosphonic acid dimethyl ester, diethylenetriaminopentakis(methylphosphonic acid), octanediphosphonic acid, and derivatives of each of these compounds. 7. The method of any of clauses 1-6, wherein at least one of the phosphonate-containing acid and the derivative thereof has the formula O R1O-P-R3 or2 where Ri, R2 and R3 are individually selected from hydrogen, an alkyl or an aryl. 8. The method of any of clauses 1-7, wherein the fluid comprises from 0.1 percent by weight to 20 percent by weight, based on the total weight of the fluid, of at least one of the phosphonate-containing acid and the derivative thereof. 9. The method of any of clauses 1-8, wherein the fluid comprises from 0.2 percent by weight to 5 percent by weight, based on the total weight of the fluid, of at least one of the phosphonate-containing acid and the derivative thereof. 10. The method of any of clauses 1-9, wherein the fluid comprises from 0.5 percent by weight to 2 percent by weight, based on the total weight of the fluid, from to MA / a / ZUZI / uuu» / z minus one of the phosphonate-containing acid and the derivative thereof. 11. The method of any of clauses 1-10, wherein contacting the metallic substrate comprises at least one of immersing the metallic substrate in a fluid bath, spraying the fluid onto the metallic substrate, and wiping the fluid onto the metallic substrate. 12. The method of clause 11, wherein contacting the metallic substrate comprises immersing the metallic substrate in a fluid bath and further comprising stirring the fluid bath by using at least one method selected from the group consisting of bubbling gas through the fluid in the bath and stirring the liquid in the bath. 13. The method of any of clauses 1-12, wherein the fluid comes into contact with the metallic substrate for a time within a range of 1 second to 40 minutes. 14. The method of any of clauses 1-13, wherein the fluid comes into contact with the metallic substrate for a time within a range of 5 seconds to 5 minutes. 15. The method of any of clauses 1-14, wherein the fluid comes into contact with the metallic substrate for a time within a range of 10 seconds to 30 seconds. 16. The method of any of clauses 1-15, wherein the functionalized phosphonate layer comprises a phosphonate group attached to the metal substrate. 17. The method of any of clauses 1-16, wherein a CIELAS (AL*) luminosity difference between the metallic substrate comprising the phosphonate functionalized layer and the metallic substrate without the phosphonate functionalized layer is not greater than 10, as measured with a BYK-Gardner Spectro Guide 45 / 0 Spectrophotometer. 18. The method of any of clauses 1-17, which further comprises, before bringing the metallic substrate into contact: cleaning the metallic substrate, wherein the cleaning comprises at least one of an alkaline cleaning, an acid cleaning and a carbon dioxide-based cleaning technique. 19. The method of any of clauses 1-18, further comprising depositing a coating layer over at least a portion of the functionalized phosphonate layer on the metallic substrate. 20. The method of clause 19, wherein the coating layer comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane. 21. The method of any of clauses 1-20, wherein an article including the metallic substrate is configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component. 22. The method of clause 21, where the article that includes the metallic substrate is a vehicle wheel. 23. An article comprising: a metallic substrate comprising aluminum or an aluminum alloy; and a functionalized phosphonate layer over at least one region of the metallic substrate. 24. The article of clause 23, wherein the functionalized phosphonate layer comprises a phosphonate group attached to the metal substrate. 25. The article of any of clauses 2324, which further comprises a coating deposited on at least one region of the functionalized phosphonate layer. 26. The article of clause 25, wherein the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester and a polyurethane. 27. The method of any of clauses 23-2 6, where an item is configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component. 28. The article of any of clauses 2326, where the article is a vehicle wheel. A person skilled in the art will recognize that the items and methods described herein, and the accompanying explanation, are used as examples for the sake of conceptual clarity, and that various configuration modifications are contemplated. Accordingly, as used herein, the specific examples / modalities provided, and the accompanying explanation, are intended to be representative of their more general classes. In general, the use of any specific example is intended to be representative of its class, and the omission of specific components, devices, operations / actions, and objects should not be considered limiting. Although this description provides descriptions of various specific aspects to illustrate different aspects of this description and / or its possible applications, it is understood by those skilled in the art that variations and modifications will occur.Accordingly, the invention or inventions described herein shall be understood to be at least as broad as claimed, and are not more narrowly defined by the particular illustrative aspects provided herein.

Claims

1. A method for treating a metallic substrate characterized in that it comprises: contacting a metallic substrate comprising at least one aluminum and an aluminum alloy with a fluid to form a phosphonate functionalized layer on at least one region of the metallic substrate, the fluid comprising at least one of a phosphonate-containing acid and a derivative thereof, wherein at least one of the phosphonate-containing acid and the derivative thereof comprises a pKa of a first acid proton, and wherein the fluid comprises a pH value at least 0.5 greater than the pKa of the first acid proton.

2. The method of claim 1, characterized in that the fluid comprises a pH at least 2 pH values ​​greater than the pKa of the first acid proton.

3. The method of any of claims 1-2, wherein the fluid comprises a pH in a range of 3.5 to 9.

5.

4. The method of any of claims 1-3, characterized in that the phosphonate-containing acid is at least one of phosphorous acid, phenylphosphonic acid, ethylphosphonic acid, octylphosphonic acid, octadecylphosphonic acid, vinylphosphonic acid, dimethyl ester of vinylphosphonic acid, diethylenetriaminopentakis(methylphosphonic acid), octane diphosphonic acid and derivatives of each of said compounds.

5. The method of any one of claims 1-4, characterized in that the at least one of the phosphonate-containing acid and the derivative thereof has the formula O R1O-P-R3 ¿R2 wherein Ri, R2 and R3 are individually selected from hydrogen, an alkyl and an aryl.

6. The method of any of claims 1-5, characterized in that the fluid comprises from 0.1 percent by weight to 20 percent by weight, based on the total weight of the fluid, of at least one of the phosphonate-containing acid and the derivative thereof.

7. The method of any of claims 1-6, characterized in that contacting the metallic substrate comprises at least one of immersing the metallic substrate in a fluid bath, spraying the fluid onto the metallic substrate, and wiping the fluid onto the metallic substrate.

8. The method of claim 7, characterized in that contacting the metallic substrate comprises immersing the metallic substrate in a fluid bath and further comprises stirring the fluid bath by using at least one method selected from the group consisting of bubbling gas through the fluid in the bath and stirring the liquid in the bath.

9. The method of any of claims 1-8, characterized in that the fluid comes into contact with the metallic substrate for a time within a range of 1 second to 40 minutes.

10. The method of any of claims 1-9, characterized in that the functionalized phosphonate layer comprises a phosphonate group attached to the metal substrate.

11. The method of any of claims 1-10, characterized in that a CIELAB luminosity difference (AL*) between the metallic substrate comprising the phosphonate functionalized layer and the metallic substrate without the phosphonate functionalized layer is not greater than 10, as measured with a BYK-Gardner Spectro Guide 45 / 0 spectrophotometer.

12. The method of any of claims 1-11, characterized in that it further comprises, prior to contacting the metallic substrate: cleaning the metallic substrate, wherein the cleaning comprises at least one of an alkaline cleaning, an acid cleaning and a carbon dioxide-based cleaning technique.

13. The method of any of claims 1-12, characterized in that it further comprises depositing a coating layer over at least a portion of the functionalized phosphonate layer on the metallic substrate.

14. The method of claim 13, characterized in that the coating layer comprises at least one of a siloxane, a silazane, a fluoropolymer, an acullico, an epoxy, a polyester, and a polyurethane. ΙνΙΛ / α / ZυΖΊ / UUU» / Z 15. An article characterized in that it comprises: a metallic substrate comprising aluminum or an aluminum alloy; and a functionalized phosphonate layer on at least one region of the metallic substrate.

16. The article according to claim 15, characterized in that the functionalized phosphonate layer comprises a phosphonate group attached to the metal substrate.

17. The article of any of claims 15-16, characterized in that it further comprises a coating deposited on at least one region of the functionalized phosphonate layer.

18. The article according to claim 17, characterized in that the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane.

19. The method of any of claims 16-18, characterized in that an article is configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component.

20. The article of any of claims 16-19, characterized in that the article is a vehicle wheel.