Patent Description:
Known systems and methods exist for providing erosion protection or edge protection of composite structures, such as aircraft composite structures. In such situations, the term "erosion" refers to physical changes to the composite as a result of exposure to an external airstream. For example, one known system and method includes use of strips of metal foil, such as titanium foil, adhered with a sealant to the cut edges of aircraft composite structures, to prevent any impact to the surface of the aircraft composite structures in an external airstream.

However, such strips of titanium foil may be heavy, expensive, and required careful handling during processing and shipping. Moreover, the application process for applying such strips of titanium foil typically requires highly trained manufacturing technicians to manually apply the strips, and such manual application may present ergonomic issues. Further, for curved surfaces and corners of cut edges, the strips of titanium foil may need to be bent and formed into a desired shape to fit over the curved surfaces and corners. This may require custom tooling to form the strips of titanium foil into the desired shape for installation, and such custom tooling may increase manufacturing costs.

Another known system and method for providing erosion protection or edge protection of composite structures, such as aircraft composite structures, includes a coating-based solution. Coatings may be either spray applied or roll applied over the edge surfaces of the composite structures, such as aircraft composite structures, to be protected. However, it may be challenging to apply such coatings in a precise area with precision thickness over long narrow surfaces. Further, care must be taken to ensure that acceptable coating coverage is achieved over cut edges and around corners of composite structures, such as aircraft composite structures, that have complex curvature.

Accordingly, there is a need in the art for an apparatus, system, and method for providing erosion protection of composite structures, such as aircraft composite structures, that improve the ease of handling and installation, that are less expensive, and that provide advantages over known products, systems, and methods.

<CIT> in accordance with its abstract states that according to a nonlimiting embodiment of the present invention, an appliqué coating is provided for a substrate. The appliqué coating includes a metal foil and a first polymer film underlying the metal foil. A topcoat overlying the metal foil may be provided as a layer of paint or as a second polymer film. An adhesive, such as a pressure sensitive adhesive, underlying the first polymer film may be provided to affix the appliqué coating to the substrate. If desired, fibers may be dispersed throughout the second polymer film to provide anti-static properties. Also, an ink layer may be provided between the metal foil and the second polymer film, if desired, for aesthetic and/or anti-static purposes.

<CIT> in accordance with its abstract states that a structure formed from composite material and method of forming a structure composite material is disclosed in which one or more metal layers are disposed on the composite material.

<CIT> in accordance with its abstract states that an appliqué for forming a surface coating to a substrate is disclosed. The appliqué contains a sectioned metal foil that provides a large area electrical circuit for connecting electrical devices. The appliqué may provide additional functions including lightning strike protection. The substrate may be an aircraft surface.

According to an aspect there is provided a laminated hybrid metallized polymer film for erosion protection of a composite structure, as defined in claim <NUM>. According to another aspect there is provided a system for erosion protection of an aircraft composite structure, as defined in claim <NUM>. According to another aspect there is provided a method for providing erosion protection of a composite structure, as defined in claim <NUM>. Example implementations of the present disclosure provide a laminated hybrid metallized polymer film, system, and method for erosion protection of composite structures, such as aircraft composite structures. As discussed in the below detailed description, versions of the laminated hybrid metallized polymer film, system, and method may provide significant advantages over known products, systems, and methods.

In a version of the disclosure, there is provided a laminated hybrid metallized polymer film for erosion protection of a composite structure. The laminated hybrid metallized polymer film comprises a metal foil layer. The laminated hybrid metallized polymer film further comprises a laminating adhesive layer underlying the metal foil layer.

The laminated hybrid metallized polymer film further comprises a polymer film layer underlying the laminating adhesive layer. The polymer film layer is laminated to the metal foil layer with the laminating adhesive layer coupled between the metal foil layer and the polymer film layer. The laminated hybrid metallized polymer film further comprises an adhesive layer underlying the polymer film layer. The adhesive layer adheres the polymer film layer to a substrate surface of the composite structure.

The metal foil layer, the laminating adhesive layer, the polymer film layer, and the adhesive layer form the laminated hybrid metallized polymer film, for application over and to the substrate surface of the composite structure.

In another version of the disclosure, there is provided a system for erosion protection of an aircraft composite structure. The system comprises a substrate surface of the aircraft composite structure. The substrate surface has one or more cut edges. The system further comprises a laminated hybrid metallized polymer film applied over and to the substrate surface of the aircraft composite structure.

The laminated hybrid metallized polymer film comprises a metal foil layer. The laminated hybrid metallized polymer film further comprises a laminating adhesive layer underlying the metal foil layer.

The laminated hybrid metallized polymer film further comprises a polymer film layer underlying the laminating adhesive layer. The polymer film layer is laminated to the metal foil layer with the laminating adhesive layer coupled between the metal foil layer and the polymer film layer.

The laminated hybrid metallized polymer film further comprises an adhesive layer underlying the polymer film layer, the adhesive layer adhering the polymer film layer to the substrate surface of the aircraft composite structure. When the aircraft composite structure is exposed to an airstream, the laminated hybrid metallized polymer film applied over and to the substrate surface provides erosion protection of the aircraft composite structure from the airstream.

In another version of the disclosure, there is provided a method for providing erosion protection of a composite structure. The method comprises the step of forming a laminated hybrid metallized polymer film.

The laminated hybrid metallized polymer film comprises a metal foil layer. The laminated hybrid metallized polymer film further comprises a laminating adhesive layer underlying the metal foil layer. The laminated hybrid metallized polymer film further comprises a polymer film layer underlying the laminating adhesive layer. The polymer film layer is laminated to the metal foil layer with the laminating adhesive layer coupled between the metal foil layer and the polymer film layer. The laminated hybrid metallized polymer film further comprises an adhesive layer underlying the polymer film layer.

The method further comprises the step of preparing a substrate surface of the composite structure, to obtain a prepared substrate surface. The method further comprises the step of applying the laminated hybrid metallized polymer film over and to the prepared substrate surface of the composite structure. The adhesive layer adheres the polymer film layer to the prepared substrate surface. When the composite structure is exposed to one or more erosion conditions, the laminated hybrid metallized polymer film applied over and to the prepared substrate surface provides erosion protection to the composite structure from the one or more erosion conditions.

The features, functions, and advantages that have been discussed can be achieved independently in various embodiments of the disclosure or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings.

The disclosure can be better understood with reference to the following detailed description taken in conjunction with the accompanying drawings which illustrate preferred and exemplary versions, but which are not necessarily drawn to scale, wherein:.

The figures shown in this disclosure represent various aspects of the versions presented, and only differences will be discussed in detail.

Disclosed versions or embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all of the disclosed versions are shown. Indeed, several different versions may be provided and should not be construed as limited to the versions set forth herein. Rather, these versions are provided so that this disclosure will be thorough and fully convey the scope of the disclosure to those skilled in the art.

The present invention relates to a laminated hybrid metallized polymer film as described in the appended claims. Preferred embodiments are covered by the dependent claims.

Referring to the Figures, <FIG> is an illustration of a functional block diagram showing exemplary versions of a laminated hybrid metallized polymer film <NUM> of the disclosure, and <FIG> is an illustration of a functional block diagram showing an exemplary version of a system <NUM> of the disclosure, where the system <NUM> incorporates versions of the laminated hybrid metallized polymer films <NUM>.

In a version of the disclosure, there is provided the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>) for erosion protection <NUM> (see <FIG>), such as erosion edge protection 14a (see <FIG>), from one or more erosion conditions <NUM> (see <FIG>), for example, an airstream <NUM> (see <FIG>), such as an external airstream 18a (see <FIG>), to prevent or minimize delamination <NUM>, of a composite structure <NUM> (see <FIG>), such as an aircraft composite structure <NUM> (see <FIG>).

The laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>) is preferably applied over and to a surface <NUM> (see <FIG>), such as a substrate surface <NUM> (see <FIG>), of the composite structure <NUM>. When the composite structure <NUM> is exposed to one or more erosion conditions <NUM>, the laminated hybrid metallized polymer film <NUM> applied over and to the surface <NUM>, such as the substrate surface <NUM>, provides erosion protection <NUM> of the composite structure <NUM> from the one or more erosion conditions <NUM>.

As shown in <FIG>, the laminated hybrid metallized polymer film <NUM> may be manufactured, or processed, in a form <NUM>, such as a tape <NUM>, including a tape roll 32a, or a tape strip 32b. Alternatively, as shown in <FIG>, the laminated hybrid metallized polymer film <NUM> may be manufactured, or processed, in the form <NUM> of an applique <NUM>, a sheet <NUM>, an overlay <NUM>, or another suitable form <NUM>.

As shown in <FIG>, <FIG>, the laminated hybrid metallized polymer film <NUM> comprises a metal foil layer <NUM>. The metal foil layer <NUM> comprises a metal (met. ) foil <NUM> (see <FIG>). As shown in <FIG>, the metal foil <NUM> may be made of one or more metal materials <NUM>, such as titanium (TI) 44a, titanium (TI) alloy 44b, nickel 44c, nickel alloy 44d, stainless steel (SS) 44e, stainless steel (SS) alloy 44f, aluminum (AL) <NUM>, aluminum (AL) alloy <NUM>, copper 44i, copper alloy 44j, or another suitable metal material <NUM>. Although these metal materials <NUM> are preferred, other suitable metal materials <NUM> may also be used. The metal materials <NUM> used are preferably good for erosion protection. As further shown in <FIG>, preferably, the metal foil layer (FL) <NUM> comprises one of, a titanium foil layer (TI FL) 40a, for example a pure titanium foil layer, a titanium (TI) alloy foil layer (FL) 40b, a nickel foil layer (FL) 40c, a nickel alloy foil layer (FL) 40d, a stainless steel foil layer (SS FL) 40e, a stainless steel (SS) alloy foil layer (FL) 40f, an aluminum foil layer (AL FL) <NUM>, an aluminum (AL) alloy foil layer (FL) <NUM>, a copper foil layer (FL) 40i, a copper alloy foil layer (FL) 40j or another suitable metal foil layer <NUM>. More preferably, the metal foil layer <NUM> comprises the titanium foil layer 40a.

In addition, one or more surfaces <NUM> (see <FIG>) of the metal foil layer <NUM>, for example, a second side 140b (see <FIG>) of the metal foil layer <NUM>, may be surface treated with one or more surface treatment processes <NUM> (see <FIG>), to obtain one or more treated surfaces 45a (see <FIG>), for example, to facilitate adhesion to a laminating adhesive layer <NUM> (see <FIG>) of the laminated hybrid metallized polymer film <NUM>. An example of a surface treatment process <NUM> that may be used includes a sol-gel process <NUM> (see <FIG>) to treat or prepare the metal foil layer <NUM>, such as a sol-gel process disclosed in <CIT>, <CIT>, and <CIT>. However, other types of surface treatment processes <NUM> may also be used to surface treat the metal foil layer <NUM> prior to undergoing a lamination process <NUM> (see <FIG>). In addition, the one or more treated surfaces 45a of the metal foil layer <NUM> may then be primed with a primer layer <NUM> (see <FIG>, <FIG>). The primer layer <NUM> may comprise a bond primer or an exterior primer, for example, an epoxy-based primer system, including a two-part system or a one-part system. The two-part system may comprise a urethane compatible epoxy primer, or another suitable two-part system. The urethane compatible epoxy primer may be used to protect metal foils <NUM> (see <FIG>), such as made of aluminum <NUM> (see <FIG>), or another metal material <NUM> (see <FIG>), and may be used to protect composite substrates. The one-part system may comprise an adhesive bond primer including a heat-curing adhesive bond primer, may comprise a corrosion inhibiting primer including a chromate-based modified epoxy primer, or may comprise another suitable one-part system. The epoxy-based primer system may contain corrosion inhibiting pigments, and some may be specifically formulated for composites.

The primer layer <NUM> is preferably applied with a primer application process <NUM> (see <FIG>). Thus, the metal foil layer <NUM> has a surface <NUM> that may be surface treated with a surface treatment process <NUM>, to obtain a treated surface 45a, and the treated surface 45a of the metal foil layer <NUM> may be primed with a primer layer <NUM>, prior to a polymer film layer <NUM> being laminated to the metal foil layer <NUM>, or prior to the metal foil layer <NUM> being laminated to the polymer film layer <NUM>.

In addition, the metal foil layer <NUM> may be processed or modified prior to forming the laminated hybrid metallized polymer film <NUM>. The metal foil layer <NUM> may have various configurations <NUM> (see <FIG>). As shown in <FIG>, the metal foil layer <NUM> may have a configuration <NUM> comprising a plain metal foil 46a (see also <FIG>), which is not processed or modified before application to the surface <NUM> (see <FIG>), such as the substrate surface <NUM> (see <FIG>), of the composite structure <NUM> (see <FIG>). Alternatively, as shown in <FIG>, the metal foil layer <NUM> may be processed or modified and have a configuration <NUM> comprising one of, a slotted metal foil 46b (see also <FIG>), a perforated metal foil 46c (see also <FIG>), an expanded metal foil 46d (see also <FIG>), a mesh metal foil 46e (see also <FIG>), or another suitable configuration <NUM>. The configurations <NUM> shown in <FIG> are discussed in further detail below.

Preferably, the metal foil layer <NUM> (see <FIG>) has a thickness <NUM> (see <FIG>) in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>). More preferably, the metal foil layer <NUM> has a thickness <NUM> in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>).

As shown in <FIG>, <FIG>, the laminated hybrid metallized polymer film <NUM> further comprises the laminating adhesive layer <NUM> underlying the metal foil layer <NUM>. The laminating adhesive layer <NUM> comprises a laminating adhesive <NUM>. The laminating adhesive <NUM> may be made of one or more laminating adhesive materials <NUM>, such as urethane 54a including polyurethane 54b, epoxy 54c, polysiloxane 54d, silicone 54e, acrylic 54f, or another suitable laminating adhesive material <NUM>. As shown in <FIG>, the laminating adhesive layer (AL) <NUM> may comprise one of, a urethane adhesive layer (AL) 50a including a polyurethane adhesive layer (AL) 50b , an epoxy adhesive layer (AL) 50c, a polysiloxane adhesive layer (AL) 50d, a silicone adhesive layer (AL) 50e, an acrylic adhesive layer (AL) 50f, or another suitable laminating adhesive layer <NUM>.

Preferably, the laminating adhesive layer <NUM> (see <FIG>) has a thickness <NUM> (see <FIG>) in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>). More preferably, the laminating adhesive layer <NUM> has a thickness <NUM> in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mil, <NUM>). A laminator apparatus <NUM> (see <FIG>), or machine, may be used to apply the laminating adhesive layer <NUM> to the metal foil layer <NUM> (see <FIG>), or to the polymer film layer <NUM> (see <FIG>), and may be used to press the metal foil layer <NUM>, the laminating adhesive layer <NUM>, and the polymer film layer <NUM> together in a lamination process <NUM> (see <FIG>).

As shown in <FIG>, <FIG>, the laminated hybrid metallized polymer film <NUM> further comprises the polymer film layer <NUM> underlying the laminating adhesive layer <NUM>. The polymer film layer <NUM> is laminated to the metal foil layer <NUM> with the laminating adhesive layer <NUM>, and the laminating adhesive layer <NUM> is coupled, or sandwiched, between the metal foil layer <NUM> and the polymer film layer <NUM>, and holds or adheres the metal foil layer <NUM> to the polymer film layer <NUM>.

The polymer film layer <NUM> comprises a polymer film <NUM> (see <FIG>). As shown in <FIG>, the polymer film <NUM> may be made of one or more polymer materials <NUM>, such as polyether ether ketone (PEEK) 64a, polyester 64b, polyethylene terephthalate (PET) 64c, polypropylene (PP) 64d, polyethylene (PE) 64e, polytrimethylene terephthalate (PTT) 64f, polyamide (PA) <NUM>, polyetherimide (PEI) <NUM>, polyvinyl chloride (PVC) 64i, polycarbonate (PC) 64j, nylon <NUM>, polyetherketoneketone (PEKK) <NUM>, polyphenylsulfone (PPSU) <NUM>, polyphenylene sulfide (PPS) 64n, ethylene chlorotrifluoroethylene (ECTFE) 64o, polyvinylidene fluorine (PVDF) 64p, or another suitable polymer material <NUM>. As further shown in <FIG>, preferably, the polymer film layer (FL) <NUM> may comprise one of, a polyether ether ketone film layer (PEEK FL) 60a, a polyester film layer (FL) 60b, a polyethylene terephthalate film layer (PET FL) 60c, a polypropylene film layer (PP FL) 60d, a polyethylene film layer (PE FL) 60e, a polytrimethylene terephthalate film layer (PTT FL) 60f, a polyamide film layer (PA FL) <NUM>, a polyetherimide film layer (PEI FL) <NUM>, a polyvinyl chloride film layer (PVC FL) 60i, a polycarbonate film layer (PC FL) 60j, a nylon film layer (FL) <NUM>, a polyetherketoneketone film layer (PEKK FL) <NUM>, a polyphenylsulfone film layer (PPSU FL) <NUM>, a polyphenylene sulfide film layer (PPS FL) 60n, an ethylene chlorotrifluoroethylene film layer (ECTFE FL) 60o, a polyvinylidene fluorine film layer (PVDF FL) 60p, or another suitable polymer film layer <NUM>.

Preferably, the polymer film layer <NUM> has a thickness <NUM> (see <FIG>) in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>). More preferably, the polymer film layer <NUM> has a thickness <NUM> in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>).

The polymer film layer <NUM> (see <FIG>) may be in the form of an elastomeric polymer backing film <NUM> (see <FIG>) that is laminated, or is configured to be laminated, to the metal foil layer <NUM>, via the laminating adhesive layer <NUM>, by using the lamination process <NUM> (see <FIG>). The polymer film layer <NUM> (see <FIG>), such as in the form of the elastomeric polymer backing film <NUM> (see <FIG>), provides flexibility and handleability to the metal foil layer <NUM>.

As shown in <FIG>, <FIG>, the laminated hybrid metallized polymer film <NUM> further comprises an adhesive layer <NUM> underlying the polymer film layer <NUM>. The adhesive layer <NUM> adheres the polymer film layer <NUM> to the surface <NUM> (see <FIG>), such as the substrate surface <NUM> (see <FIG>), of the composite structure <NUM> (see <FIG>), such as the aircraft composite structure <NUM> (see <FIG>).

In one version, as shown in <FIG>, <FIG>, and discussed below with regard to <FIG>, the adhesive layer (AL) <NUM> of the laminated hybrid metallized polymer film <NUM> may comprise one of, a sealant adhesive layer (AL) <NUM> including a polythioether sealant adhesive layer (AL) 72a, a polysulfide (PS) sealant adhesive layer (AL) 72b, or another suitable sealant adhesive layer <NUM>.

In another version, as shown in <FIG>, <FIG>, and discussed below with regard to <FIG>, the adhesive layer <NUM> of the laminated hybrid metallized polymer film <NUM> may comprise a pressure sensitive adhesive (PSA) layer <NUM>. Preferably, the PSA layer <NUM> may comprise acrylic 74a (see <FIG>), a modified (mod. ) acrylic 74b (see <FIG>), a silicone-based pressure sensitive adhesive (PSA) 74c (see <FIG>), or another suitable PSA layer <NUM>. The PSA layer <NUM> is preferably pre-applied to a hybrid metal film portion <NUM> (see <FIG>) made up of the metal foil layer <NUM>, the laminating adhesive layer <NUM>, and the polymer film layer <NUM>, and installation is a peel-and-stick process, like an applique.

In yet another version, as shown in <FIG>, <FIG>, and discussed below with regard to <FIG>, the adhesive layer <NUM> of the laminated hybrid metallized polymer film <NUM> may comprise a curable film adhesive layer (AL) <NUM> including a heat curable film adhesive layer (AL) 76a. Preferably, the curable film adhesive layer <NUM>, such as the heat curable film adhesive layer 76a, comprises epoxy film adhesives, such as toughened epoxy structural film adhesives, or another suitable film adhesive. Preferably, the epoxy film adhesives, such as the toughened epoxy structural film adhesives, provide high strength permanent structural bonds that are resistant to harsh environments and provide high durability. The heat curable film adhesive layer 76a preferably requires heat activation for cure and vacuum bagging for bond strength. The curable film adhesive layer <NUM>, such as the heat curable film adhesive layer 76a, may be supplied as part of the hybrid metal film portion <NUM> (see <FIG>), or may be a separate material used for installation.

The effective elevated temperature for heating and curing the heat curable film adhesive layer 76a (see <FIG>) and the hybrid metal film portion <NUM> (see <FIG>) is preferably in a range of from <NUM>°F (two-hundred degrees Fahrenheit) to <NUM>°F (three-hundred fifty degrees Fahrenheit), and more preferably, in a range of from <NUM>°F (two-hundred degrees Fahrenheit) to <NUM>°F (two-hundred seventy-five degrees Fahrenheit), and most preferably, at a temperature of <NUM>°F (two-hundred fifty degrees Fahrenheit). The effective period of time for heating and curing the heat curable film adhesive layer 76a (see <FIG>) and the hybrid metal film portion <NUM> (see <FIG>) is preferably in a range of from <NUM> (thirty) minutes to about <NUM> (four) hours, depending on the temperature used for heating and curing, and more preferably. Preferably, the heating and curing takes place under vacuum, such as vacuum bagging. The effective pressure for heating and curing the heat curable film adhesive layer 76a (see <FIG>) and the hybrid metal film portion <NUM> (see <FIG>) is preferably in a range of from <NUM> psi (two pounds per square inch, <NUM> MPa) to <NUM> (eighty) psi (<NUM> MPa), and more preferably, in a range of from <NUM> (five) psi (<NUM> MPa) to <NUM> (twenty) psi (<NUM> MPa). The temperature, pressure, and time selected for the heating and curing is preferably selected based on the type of heat curable film adhesive layer 76a used.

In the present invention, the adhesive layer <NUM> has a thickness <NUM> in a range of from <NUM> inch (<NUM>) to <NUM> inch (<NUM>). More preferably, the adhesive layer <NUM> has a thickness <NUM> in a range of from <NUM> inch (<NUM> mils, <NUM>) to <NUM> inch (<NUM> mils, <NUM>).

As shown in <FIG>, <FIG> the metal foil layer <NUM>, the laminating adhesive layer <NUM>, the polymer film layer <NUM>, and the adhesive layer <NUM> form the laminated hybrid metallized polymer film <NUM>. The metal foil layer <NUM>, the laminating adhesive layer <NUM>, and the polymer film layer <NUM> comprise the hybrid metal film portion <NUM> (see <FIG>) of the laminated hybrid metallized polymer film <NUM>, and the adhesive layer <NUM> comprises a bonding adhesive portion <NUM> (see <FIG>) of the laminated hybrid metallized polymer film <NUM>. The bonding adhesive portion <NUM> bonds, or is configured to bond, the hybrid metal film portion <NUM> to the surface <NUM>, such as the substrate surface <NUM>, of the composite structure <NUM>, such as the aircraft composite structure <NUM>.

As shown in <FIG>, in another version of the disclosure, there is provided the system <NUM> for erosion protection <NUM>, such as erosion edge protection 14a, of a composite structure <NUM>, such as an aircraft composite structure <NUM>, for example, when the composite structure <NUM>, such as the aircraft composite structure <NUM>, is exposed to one or more erosion conditions <NUM>, such as an airstream <NUM>, for example, an external airstream 18a.

As shown in <FIG>, the system <NUM> comprises the composite structure <NUM>, such as the aircraft composite structure <NUM>. The aircraft composite structure <NUM> (see <FIG>) may comprise an aircraft composite part 24a (see <FIG>), for example, a carbon fiber reinforced plastic (CFRP) part 24b (see <FIG>), or a composite laminate 24c (see <FIG>). As shown in <FIG>, the system <NUM> further comprises the surface <NUM>, such as the substrate surface <NUM>, of the composite structure <NUM>, such as the aircraft composite structure <NUM>. The composite structure <NUM>, such as the aircraft composite structure <NUM>, may have surfaces <NUM>, such as the substrate surfaces <NUM>, comprising curved surfaces <NUM>, that each have a curved configuration <NUM> (see <FIG>) with a complex curvature <NUM> (see <FIG>). Installation or application of the laminated hybrid metallized polymer film <NUM> on such curved surfaces <NUM> is facilitated due to the formability of the laminated hybrid metallized polymer film <NUM>.

As shown in <FIG>, the surface <NUM>, such as the substrate surface <NUM>, of the composite structure <NUM>, such as the aircraft composite structure <NUM>, may have one or more edges <NUM>, such as one or more leading edges 86a. The one or more edges <NUM> may include one or more cut edges 86b (see <FIG>) with corners <NUM> (see <FIG>), where the cut edges 86b and/or the corners <NUM> may protrude and may need to be covered with the laminated hybrid metallized polymer film <NUM>, to protect against erosion conditions <NUM>, and to prevent or minimize delamination <NUM> (see <FIG>) of the one or more cut edges 86b. As shown in <FIG>, the laminated hybrid metallized polymer film <NUM> is preferably used on surfaces <NUM>, such as the substrate surfaces <NUM>, for example, a prepared substrate surfaces 28a, of one or more edges <NUM>, such as one or more leading edges 86a, of composite structures <NUM>, such as aircraft composite structures <NUM>. As shown in <FIG>, the leading edges 86a may include leading edges 86a of wing panels <NUM>, barrel sections <NUM>, passenger doors <NUM>, access doors <NUM>, window surrounds <NUM>, horizontal stabilizers <NUM>, and vertical stabilizers <NUM> of air vehicles <NUM> (see <FIG>), such as aircraft 160a (see <FIG>).

The surface <NUM>, such as the substrate surface <NUM>, may be prepared or treated with one or more surface treatment processes <NUM> (see <FIG>), prior to application of the laminated hybrid metallized polymer film <NUM>, to obtain the prepared substrate surface 28a (see <FIG>). The one or more surface treatment processes <NUM> (see <FIG>) may facilitate adhesion of the laminated hybrid metallized polymer film <NUM> to the surface <NUM>, such as the substrate surface <NUM>.

As shown in <FIG>, the system <NUM> may further comprise an edge seal layer <NUM> that may optionally be applied over and to the surface <NUM>, such as the substrate surface <NUM>, to become part of the prepared substrate surface 28a, prior to the laminated hybrid metallized polymer film <NUM> being applied over and to the surface <NUM>, such as the substrate surface <NUM>. The edge seal layer <NUM> comprises an edge seal material <NUM> that may comprise urethanes, thioethers, epoxies, polysulfides, or another suitable edge seal material <NUM>. The edge seal layer <NUM> may be applied to, and smoothed over, the surface <NUM>, such as the substrate surface <NUM>. The edge seal layer <NUM> is preferably applied using an edge seal application process <NUM> (see <FIG>). After the edge seal layer <NUM> is applied to the surface <NUM>, such as the substrate surface <NUM>, the edge seal layer <NUM> may be cleaned and prepared for application of a primer layer <NUM> (see <FIG>), or alternatively, for direct application of the laminated hybrid metallized polymer film <NUM>.

Preferably, the edge seal layer <NUM> has a thickness <NUM> (see <FIG>) in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>). More preferably, the edge seal layer <NUM> has a thickness <NUM> in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>).

As shown in <FIG>, the system <NUM> may further comprise the primer layer <NUM> that may be optionally applied over and to the edge seal layer <NUM>, prior to the laminated hybrid metallized polymer film <NUM> being applied over and to the surface <NUM>, such as the substrate surface <NUM>, and to become part of the prepared substrate surface 28a. The primer layer <NUM> may comprise a primer material <NUM> comprising a bond primer or an exterior primer, for example, an epoxy-based primer system, including a two-part system or a one-part system. The two-part system may comprise a urethane compatible epoxy primer, or another suitable two-part system. The one-part system may comprise an adhesive bond primer including a heat-curing adhesive bond primer, may comprise a corrosion inhibiting primer including a chromate-based modified epoxy primer, or may comprise another suitable one-part system. The epoxy-based primer system may contain corrosion inhibiting pigments, and some may be specifically formulated for composites.

The primer layer <NUM> is preferably applied with a primer application process <NUM> (see <FIG>). After the primer layer <NUM> is applied to and over the edge seal layer <NUM>, the primer layer <NUM> may be cleaned and prepared for application of the laminated hybrid metallized polymer film <NUM>.

In another version, the primer layer <NUM> may be applied directly to and over the surface <NUM>, such as the substrate surface <NUM>, without using the edge seal layer <NUM>. In yet another version, neither the edge seal layer <NUM> nor the primer layer <NUM> is used, and the laminated hybrid metallized polymer film <NUM> is applied directly to the surface <NUM>, such as the substrate surface <NUM>, for example, the prepared substrate surface 28a, of the composite structure <NUM>, such as the aircraft composite structure <NUM>.

Preferably, the primer layer <NUM> has a thickness <NUM> (see <FIG>) in a range of from <NUM> inch (<NUM> mil, <NUM>) to <NUM> inch (<NUM> mils, <NUM>). More preferably, the primer layer <NUM> has a thickness <NUM> in a range of from. <NUM> inch (<NUM> mils, <NUM>) to <NUM> inch (<NUM> mils, <NUM>).

The system <NUM> (see <FIG>) comprises one or more versions of the laminated hybrid metallized polymer film <NUM>, as discussed above, applied over and to the surface <NUM>, such as the substrate surface <NUM>, for example, the prepared substrate surface 28a, of the composite structure <NUM>, such as the aircraft composite structure <NUM>, with or without the edge seal layer <NUM> and/or the primer layer <NUM>.

As discussed above, and as shown in <FIG>, the laminated hybrid metallized polymer film <NUM> comprises the metal foil layer <NUM>. As shown in <FIG>, the metal foil layer <NUM> preferably comprises a titanium foil layer 40a, a titanium alloy foil layer 40b, a nickel foil layer 40c, a nickel alloy foil layer 40d, a stainless steel foil layer 40e, a stainless steel alloy foil layer 40f, an aluminum foil layer <NUM>, an aluminum alloy foil layer <NUM>, a copper foil layer 40i, a copper alloy foil layer 40j, or another suitable metal foil layer <NUM>. More preferably, the metal foil layer <NUM> comprises the titanium foil layer 40a.

As discussed above, and as shown in <FIG>, the laminated hybrid metallized polymer film <NUM> further comprises the laminating adhesive layer <NUM> underlying the metal foil layer <NUM>. As shown in <FIG>, the laminating adhesive layer <NUM> may comprise a urethane adhesive layer 50a including a polyurethane adhesive layer 50b, an epoxy adhesive layer 50c, a polysiloxane adhesive layer 50d, a silicone adhesive layer 50e, an acrylic adhesive layer 50f, or another suitable laminating adhesive layer <NUM>.

As discussed above, and as shown in <FIG>, the laminated hybrid metallized polymer film <NUM> further comprises the polymer film layer <NUM> underlying the laminating adhesive layer <NUM>. The polymer film layer <NUM> is laminated to the metal foil layer <NUM> with the laminating adhesive layer <NUM>, and the laminating adhesive layer <NUM> is coupled between the metal foil layer <NUM> and the polymer film layer <NUM>. As shown in <FIG>, the polymer film layer <NUM> may comprise a polyether ether ketone (PEEK) film layer 60a, a polyester film layer 60b, a polyethylene terephthalate (PET) film layer 60c, a polypropylene (PP) film layer 60d, a polyethylene (PE) film layer 60e, a polytrimethylene terephthalate (PTT) film layer 60f, a polyamide (PA) film layer <NUM>, a polyetherimide (PEI) film layer <NUM>, a polyvinyl chloride (PVC) film layer 60i, a polycarbonate (PC) film layer 60j, a nylon film layer <NUM>, a polyetherketoneketone (PEKK) film layer <NUM>, a polyphenylsulfone (PPSU) film layer <NUM>, a polyphenylene sulfide (PPS) film layer 60n, an ethylene chlorotrifluoroethylene (ECTFE) film layer 60o, a polyvinylidene fluorine (PVDF) film layer 60p, or another suitable polymer film layer <NUM>.

As discussed above, and as shown in <FIG>, the laminated hybrid metallized polymer film <NUM> further comprises the adhesive layer <NUM> underlying the polymer film layer <NUM>. The adhesive layer <NUM> adheres the polymer film layer <NUM> to the surface <NUM> (see <FIG>), such as the substrate surface <NUM> (see <FIG>) of the composite structure <NUM> (see <FIG>), such as the aircraft composite structure <NUM> (see <FIG>).

In one version, as shown in <FIG>, and discussed below with regard to <FIG>, the adhesive layer <NUM> of the laminated hybrid metallized polymer film <NUM> may comprise the sealant adhesive layer <NUM> including the polythioether sealant adhesive layer 72a, the polysulfide sealant adhesive layer 72b, or another suitable sealant adhesive layer <NUM>. In another version, as shown in <FIG>, and discussed below with regard to <FIG>, the adhesive layer <NUM> of the laminated hybrid metallized polymer film <NUM> may comprise the pressure sensitive adhesive (PSA) layer <NUM>. In yet another version, as shown in <FIG>, and discussed below with regard to <FIG>, the adhesive layer <NUM> of the laminated hybrid metallized polymer film <NUM> may comprise the curable film adhesive layer <NUM> including the heat curable film adhesive layer 76a.

As shown in <FIG>, the metal foil layer <NUM>, the laminating adhesive layer <NUM>, the polymer film layer <NUM>, and the adhesive layer <NUM> form the laminated hybrid metallized polymer film <NUM>. The laminated hybrid metallized polymer film <NUM> is preferably applied over and to the surface <NUM> (see <FIG>), such as the substrate surface <NUM> (see <FIG>) of the composite structure <NUM> (see <FIG>), such as the aircraft composite structure <NUM> (see <FIG>). When the composite structure <NUM>, such as the aircraft composite structure <NUM>, is exposed to one or more erosion conditions <NUM> (see <FIG>), the laminated hybrid metallized polymer film <NUM> applied over and to the surface <NUM>, such as the substrate surface <NUM>, provides erosion protection <NUM> (see <FIG>), such as erosion edge protection 14a (see <FIG>), of the composite structure <NUM>, such as the aircraft composite structure <NUM>, from the one or more erosion conditions <NUM>, such as an airstream <NUM> (see <FIG>), for example, an external airstream 18a (see <FIG>).

When the composite structure <NUM>, such as the aircraft composite structure <NUM>, is exposed to the erosion condition <NUM>, such as the airstream <NUM>, for example, the external airstream 18a, the laminated hybrid metallized polymer film <NUM> applied over and to the surface <NUM>, such as the substrate surface <NUM>, prevents or minimizes delamination <NUM> (see <FIG>) of the one or more cut edges 86b (see <FIG>) of the surface <NUM>, such as the substrate surface <NUM>, of the composite structure <NUM>, such as the aircraft composite structure <NUM>, and provides erosion protection <NUM> (see <FIG>) of the composite structure <NUM>, such as the aircraft composite structure <NUM>, from the erosion condition <NUM>, such as the airstream <NUM>.

Now referring to <FIG>, various configurations <NUM> of the metal foil layer <NUM> are shown. Depending on how and where the laminated hybrid metallized polymer film <NUM> is applied to the surface <NUM> (see <FIG>), such as the substrate surface <NUM> (see <FIG>), for example, the prepared substrate surface 28a (see <FIG>), of the composite structure <NUM>, such as the aircraft composite structure <NUM>, the metal foil layer <NUM> may be processed or modified prior to forming the laminated hybrid metallized polymer film <NUM>. For example, for composite structures <NUM>, such as the aircraft composite structures <NUM>, with curved surfaces <NUM> (see <FIG>) having a curved configuration <NUM> (see <FIG>) with a complex curvature <NUM> (see <FIG>), it may be desirable to prepare or modify the metal foil layer <NUM> to facilitate application and fitting of the laminated hybrid metallized polymer film <NUM> around and over such curved surfaces <NUM>.

<FIG> is an illustration of a top view of the metal foil layer <NUM> having a configuration <NUM> comprising a plain metal foil 46a that may be used in a version of the laminated hybrid metallized polymer film <NUM> (see <FIG>) of the disclosure. The plain metal foil 46a, shown in FIG. 2A, has not been processed or modified further and has a closed continuous surface <NUM> without any slots, perforations, openings, or patterns.

<FIG> is an illustration of a top view of the metal foil layer <NUM> with a configuration <NUM> comprising a slotted metal foil 46b that may be used in a version of a laminated hybrid metallized polymer film <NUM> (see <FIG>) of the disclosure. As shown in <FIG>, the slotted metal foil 46b has a plurality of slots <NUM> formed through a surface <NUM> of the slotted metal foil 46b. The slotted metal foil 46b may be formed by cutting with a slot cutting apparatus the plurality of slots <NUM>, or elongated holes, in a staggered or side-by-side pattern, or another suitable pattern.

<FIG> is an illustration of a top view of the metal foil layer <NUM> with a configuration <NUM> comprising a perforated metal foil 46c that may be used in a version of a laminated hybrid metallized polymer film <NUM> (see <FIG>) of the disclosure. As shown in <FIG>, the perforated metal foil 46c has a plurality of perforations <NUM> formed through a surface <NUM> of the perforated metal foil 46c. The perforated metal foil 46c may be formed by cutting or punching with a hole cutting machine the plurality of perforations <NUM>, or holes, in straight rows or a staggered pattern, or another suitable pattern.

<FIG> is an illustration of a top view of the metal foil layer <NUM> with a configuration <NUM> comprising an expanded metal foil 46d that may be used in a version of a laminated hybrid metallized polymer film <NUM> (see <FIG>) of the disclosure. As shown in <FIG>, the expanded metal foil 46d has a plurality of openings <NUM> in a diamond-shaped pattern <NUM> formed through a surface <NUM> of the expanded metal foil 46d. The expanded metal foil 46d may be formed by cutting with a slot cutting machine multiple slits in the metal foil layer <NUM>, and then stretching the metal foil layer <NUM> that has been cut, to form the diamond-shaped pattern <NUM>.

<FIG> is an illustration of a top view of the metal foil layer <NUM> with a configuration <NUM> comprising a mesh metal foil 46e that may be used in a version of a laminated hybrid metallized polymer film <NUM> (see <FIG>) of the disclosure. As shown in <FIG>, the mesh metal foil 46e has a woven mesh pattern <NUM> formed on, or in, a surface <NUM> of the mesh metal foil 46e with a metal mesh forming machine.

Now referring to <FIG>, <FIG> is a schematic cross-sectional side view of an exemplary version of a laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, of the disclosure. <FIG> is a schematic cross-sectional side view of the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, of <FIG>, applied to a version of a substrate surface <NUM>, such as a prepared substrate surface 28a. <FIG> is a schematic cross-sectional side view of the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, of <FIG>, applied to another version of a substrate surface <NUM>, such as the prepared substrate surface 28a.

As shown in <FIG>, the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, comprises the metal foil layer <NUM>, the laminating adhesive layer <NUM>, the polymer film layer <NUM>, and the adhesive layer <NUM>, where the adhesive layer <NUM> comprises a sealant adhesive layer <NUM>. The sealant adhesive layer <NUM> (see <FIG>) may comprise a polythioether sealant adhesive layer 72a (see <FIG>), a polysulfide sealant adhesive layer 72b (see <FIG>), or another suitable sealant adhesive layer <NUM>.

As shown in <FIG>, the metal foil layer <NUM> has a first side 140a and a second side 140b, the laminating adhesive layer <NUM> has a first side 142a and a second side 142b, the polymer film layer <NUM> has a first side 144a and a second side 144b, and the adhesive layer <NUM>, such as the sealant adhesive layer <NUM>, has a first side 146a and a second side 146b. As shown in <FIG>, the second side 140b of the metal foil layer <NUM> is adjacent to, and coupled or attached to, the first side 142a of the laminating adhesive layer <NUM>, and the second side 142b of the laminating adhesive layer <NUM> is adjacent to, and coupled or attached to, the first side 144a of the polymer film layer <NUM>. As further shown in <FIG>, the second side 144b of the polymer film layer <NUM> is adjacent to, and coupled or attached to, the first side 146a of the sealant adhesive layer <NUM>.

<FIG> shows the system <NUM>, such as in the form of system 12a, comprising the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, and the composite structure <NUM> with the substrate surface <NUM>, such as the prepared substrate surface 28a. <FIG> further shows the edge seal layer <NUM> applied over and to the substrate surface <NUM>, and shows the primer layer <NUM> applied over and to the edge seal layer <NUM>. As shown in <FIG>, the primer layer <NUM> has a first side 148a and a second side 148b, and the edge seal layer <NUM> has a first side 150a and a second side 150b.

As shown in <FIG>, laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, is applied directly to the primer layer <NUM>. The second side 146b (see <FIG>) of the sealant adhesive layer <NUM> (see <FIG>) is adjacent to, and coupled or attached to, the first side 148a of the primer layer <NUM>. As shown in <FIG>, the second side 148b of the primer layer <NUM> is adjacent to, and coupled or attached to, the first side 150a of the edge seal layer <NUM>, and the second side 150b of the edge seal layer <NUM> is adjacent to, and coupled or attached to, the substrate surface <NUM>, such as the prepared substrate surface 28a, of the composite structure <NUM>.

<FIG> shows the system <NUM>, such as in the form of system 12b, comprising the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, and the composite structure <NUM> with the substrate surface <NUM>, such as the prepared substrate surface 28a, but with no primer layer <NUM> (see <FIG>) and with no edge seal layer <NUM> (see <FIG>) on the substrate surface <NUM>. <FIG> shows the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, applied directly to the substrate surface <NUM>, such as the prepared substrate surface 28a. The second side 146b (see <FIG>) of the sealant adhesive layer <NUM> (see <FIG>) is adjacent to, and coupled or attached to, the substrate surface <NUM>, such as the prepared substrate surface 28a, of the composite structure <NUM>.

Now referring to <FIG>, <FIG> is a schematic cross-sectional side view of another exemplary version of a laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, of the disclosure. <FIG> is a schematic cross-sectional side view of the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, of <FIG>, applied to a version of a substrate surface <NUM>, such as a prepared substrate surface 28a. <FIG> is a schematic cross-sectional side view of the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, of <FIG>, applied to another version of a substrate surface <NUM>, such as the prepared substrate surface 28a.

As shown in <FIG>, the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10a, comprises the metal foil layer <NUM> that has been surface treated and primed with a primer layer <NUM>, and comprises the laminating adhesive layer <NUM>, the polymer film layer <NUM>, and the adhesive layer <NUM>, where the adhesive layer <NUM> comprises a pressure sensitive adhesive (PSA) layer <NUM>. The PSA layer <NUM> (see <FIG>) comprising the bonding adhesive portion <NUM> (see <FIG>), is preferably pre-applied to the hybrid metal film portion <NUM> (see <FIG>), and installation is preferably a peel-and-stick process, for example, in the form <NUM> (see <FIG>) of an applique <NUM> (see <FIG>).

As shown in <FIG>, the metal foil layer <NUM> has the first side 140a and the second side 140b, the primer layer <NUM> of the metal foil layer <NUM> has a first side 151a and a second side 151b, the laminating adhesive layer <NUM> has the first side 142a and the second side 142b, the polymer film layer <NUM> has the first side 144a and the second side 144b, and the adhesive layer <NUM>, such as the PSA layer <NUM>, has a first side 152a and a second side 152b. As shown in <FIG>, the second side 140b of the metal foil layer <NUM> is adjacent to, and coupled or attached to, the first side 151a of the primer layer <NUM>, and the second side 151b of the primer layer <NUM> is adjacent to, and coupled or attached to, the first side 142a of the laminating adhesive layer <NUM>, and the second side 142b of the laminating adhesive layer <NUM> is adjacent to, and coupled or attached to, the first side 144a of the polymer film layer <NUM>. As further shown in <FIG>, the second side 144b of the polymer film layer <NUM> is adjacent to, and coupled or attached to, the first side 152a of the PSA layer <NUM>.

<FIG> shows the system <NUM>, such as in the form of system 12c, comprising the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, and the composite structure <NUM> with the substrate surface <NUM>, such as the prepared substrate surface 28a. <FIG> further shows the edge seal layer <NUM> applied over and to the substrate surface <NUM>, and shows the primer layer <NUM> applied over and to the edge seal layer <NUM>. As shown in <FIG>, the primer layer <NUM> has the first side 148a and the second side 148b, and the edge seal layer <NUM> has the first side 150a and the second side 150b.

As shown in <FIG>, laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, is applied directly to the primer layer <NUM>. The second side 152b (see <FIG>) of the PSA layer <NUM> (see <FIG>) is adjacent to, and coupled or attached to, the first side 148a of the primer layer <NUM>. As shown in <FIG>, the second side 148b of the primer layer <NUM> is adjacent to, and coupled or attached to, the first side 150a of the edge seal layer <NUM>, and the second side 150b of the edge seal layer <NUM> is adjacent to, and coupled or attached to, the substrate surface <NUM>, such as the prepared substrate surface 28a, of the composite structure <NUM>.

<FIG> shows the system <NUM>, such as in the form of system 12d, comprising the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, and the composite structure <NUM> with the substrate surface <NUM>, such as the prepared substrate surface 28a, but with no primer layer <NUM> (see <FIG>) and with no edge seal layer <NUM> (see <FIG>) on the substrate surface <NUM>. <FIG> shows the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b, applied directly to the substrate surface <NUM>, such as the prepared substrate surface 28a. The second side 152b (see <FIG>) of the PSA layer <NUM> (see <FIG>) is adjacent to, and coupled or attached to, the substrate surface <NUM>, such as the prepared substrate surface 28a, of the composite structure <NUM>.

Now referring to <FIG>, <FIG> is a schematic cross-sectional side view of yet another exemplary version of a laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, of the disclosure. <FIG> is a schematic cross-sectional side view of the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, of <FIG>, applied to a version of a substrate surface <NUM>, such as a prepared substrate surface 28a. <FIG> is a schematic cross-sectional side view of the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, of <FIG>, applied to another version of a substrate surface <NUM>, such as the prepared substrate surface 28a.

As shown in <FIG>, the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, comprises the metal foil layer <NUM>, the laminating adhesive layer <NUM>, the polymer film layer <NUM>, and the adhesive layer <NUM>, where the adhesive layer <NUM> comprises a curable film adhesive layer <NUM>. The curable film adhesive layer <NUM> (see <FIG>, <FIG>) may comprise a heat curable film adhesive layer 76a (see <FIG>), or another suitable curable film adhesive layer <NUM>. The heat curable film adhesive layer 76a requires heat activation for cure and vacuum bagging for bond strength.

As shown in <FIG>, the metal foil layer <NUM> has the first side 140a and the second side 140b, the laminating adhesive layer <NUM> has the first side 142a and the second side 142b, the polymer film layer <NUM> has the first side 144a and the second side 144b, and the adhesive layer <NUM>, such as the curable film adhesive layer <NUM>, has a first side 154a and a second side 154b. As shown in <FIG>, the second side 140b of the metal foil layer <NUM> is adjacent to, and coupled or attached to, the first side 142a of the laminating adhesive layer <NUM>, and the second side 142b of the laminating adhesive layer <NUM> is adjacent to, and coupled or attached to, the first side 144a of the polymer film layer <NUM>. As further shown in <FIG>, the second side 144b of the polymer film layer <NUM> is adjacent to, and coupled or attached to, the first side 154a of the curable film adhesive layer <NUM>.

<FIG> shows the system <NUM>, such as in the form of system 12e, comprising the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, and the composite structure <NUM> with the substrate surface <NUM>, such as the prepared substrate surface 28a. <FIG> further shows the edge seal layer <NUM> applied over and to the substrate surface <NUM>, and shows the primer layer <NUM> applied over and to the edge seal layer <NUM>. As shown in <FIG>, the primer layer <NUM> has the first side 148a and the second side 148b, and the edge seal layer <NUM> has the first side 150a and the second side 150b.

As shown in <FIG>, laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, is applied directly to the primer layer <NUM>. The second side 154b (see <FIG>) of the curable film adhesive layer <NUM> (see <FIG>) is adjacent to, and coupled or attached to, the first side 148a of the primer layer <NUM>. As shown in <FIG>, the second side 148b of the primer layer <NUM> is adjacent to, and coupled or attached to, the first side 150a of the edge seal layer <NUM>, and the second side 150b of the edge seal layer <NUM> is adjacent to, and coupled or attached to, the substrate surface <NUM> of the composite structure <NUM>.

<FIG> shows the system <NUM>, such as in the form of system 12f, comprising the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, and the composite structure <NUM> with the substrate surface <NUM>, such as the prepared substrate surface 28a, but with no primer layer <NUM> (see <FIG>) and with no edge seal layer <NUM> (see <FIG>) on the substrate surface <NUM>. <FIG> shows the laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10c, applied directly to the substrate surface <NUM>, such as the prepared substrate surface 28a. The second side 154b (see <FIG>) of the curable film adhesive layer <NUM> (see <FIG>) is adjacent to, and coupled or attached to, the substrate surface <NUM>, such as the prepared substrate surface 28a, of the composite structure <NUM>.

An example of a version of a laminated hybrid metallized polymer film <NUM>, such as in the form of laminated hybrid metallized polymer film 10b (see <FIG>), that includes a pressure sensitive adhesive (PSA) layer, was formed. Two (<NUM>) pieces of <NUM> inch, <NUM> thick commercially pure titanium (CP Ti) metal foil were cleaned and surface treated with a sol-gel process, and primed with a primer layer. The titanium foil layer was then laminated, using a laminating adhesive in the form of a two-part urethane adhesive layer, to a <NUM> inch, <NUM> thick polymer film layer in the form of a polyetheretherketone (PEEK) film layer, backed with a pressure sensitive adhesive (PSA) layer. For the example of the laminated hybrid metallized polymer film formed, the lamination process of laminating the titanium foil layer to the PEEK film layer was performed using a laboratory-scale Mayer rod drawdown coating system. Larger scale quantities of this lamination may be fabricated using industrial roll-to-roll systems.

The laminated hybrid metallized polymer film formed was then installed on substrate surface edges of a candidate carbon fiber reinforced plastic (CFRP) part to make a prototype part. Installation of the laminated hybrid metallized polymer film was fast and simple, due to the handleability of the laminated hybrid metallized polymer film. The PSA layer acted as a polymer backing film and added flexibility to the hybrid metal film portion of the titanium metal foil laminated to the PEEK film layer, and made it easier to install the titanium metal foil portion without creasing or other possible unintended damage. The use of the PSA layer greatly simplified the adhering process to the substrate surface edges of the CFRP part. This exemplary version of the laminated hybrid metallized polymer film would be particularly appropriate in areas that do not have significant fluid exposure, as PSA adhesives have limited fluid exposure. The laminated hybrid metallized polymer film provided erosion edge protection to the substrate surface edges of the CFRP part (composite structure) that were covered by the laminated hybrid metallized polymer film.

Now referring to <FIG> is an illustration of a perspective view of an air vehicle <NUM>, such as in the form of aircraft 160a, that includes one or more versions of the laminated hybrid metallized polymer film <NUM> of the disclosure applied to one or more composite structures <NUM>, such as one or more aircraft composite parts 24a. As shown in <FIG>, the air vehicle <NUM>, such as in the form of aircraft 160a, comprises a fuselage <NUM>, a nose <NUM>, a cockpit <NUM>, wings <NUM> coupled to the fuselage <NUM>, engines <NUM>, and a tail <NUM> including a first tail portion <NUM>, for example, a vertical stabilizer <NUM>, and second tail portions <NUM>, for example, horizontal stabilizers <NUM>.

As further shown in <FIG>, the laminated hybrid metallized polymer film <NUM> may preferably be used to cover one or more leading edges 86a, of composite structures <NUM>, such as aircraft composite structures <NUM>. As shown in <FIG>, the leading edges 86a that may be covered may include leading edges 86a of wing panels <NUM>, barrel sections <NUM>, passenger doors <NUM>, access doors <NUM>, window surrounds <NUM>, horizontal stabilizers <NUM>, and vertical stabilizers <NUM> of the air vehicle <NUM>, such as the aircraft 160a.

In an exemplary version, the composite structure <NUM> (see <FIG>) comprises the aircraft composite structure <NUM> (see <FIG>) on the air vehicle <NUM> (see <FIG>), such as the aircraft 160a (see <FIG>). In other versions of the composite structure <NUM> (see <FIG>), the composite structure <NUM> may comprise a rotorcraft composite structure on a rotorcraft, a spacecraft composite structure on a spacecraft, a satellite composite structure on a satellite, a watercraft composite structure on a watercraft, an automobile composite structure on an automobile, a truck composite structure on a truck, a windmill blade composite structure on a windmill, or another suitable composite structure <NUM>.

Now referring to <FIG> is an illustration of a flow diagram of a version of a method <NUM> of the disclosure. In another version of the disclosure, there is provided the method <NUM> for providing erosion protection <NUM> (see <FIG>) of a composite structure <NUM> (see <FIG>), such as an aircraft composite structure <NUM> (see <FIG>).

The blocks in <FIG> represent operations and/or portions thereof, or elements, and lines connecting the various blocks do not imply any particular order or dependency of the operations or portions thereof, or elements. <FIG> and the disclosure of the steps of the method <NUM> set forth herein should not be interpreted as necessarily determining a sequence in which the steps are to be performed. Rather, although one illustrative order is indicated, it is to be understood that the sequence of the steps may be modified when appropriate. Accordingly, certain operations may be performed in a different order or simultaneously.

As shown in <FIG>, the method <NUM> comprises the step of forming <NUM> a laminated hybrid metallized polymer film <NUM> (see <FIG>). As discussed in detail above, the laminated hybrid metallized polymer film <NUM> comprises a metal foil layer <NUM> (see <FIG>), a laminating adhesive layer <NUM> (see <FIG>) underlying the metal foil layer <NUM>, and a polymer film layer <NUM> (see <FIG>) underlying the laminating adhesive layer <NUM>, where the metal foil layer <NUM>, the laminating adhesive layer <NUM>, and the polymer film layer <NUM> preferably comprise the hybrid metal film portion <NUM> (see <FIG>) of the laminated hybrid metallized polymer film <NUM>. The polymer film layer <NUM> is laminated to the metal foil layer <NUM> with the laminating adhesive layer <NUM> coupled between the metal foil layer <NUM> and the polymer film layer <NUM>.

As discussed in detail above, the laminated hybrid metallized polymer film <NUM> further comprises an adhesive layer <NUM> (see <FIG>) underlying the polymer film layer <NUM>.

The forming <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise forming the laminated hybrid metallized polymer film <NUM> (see <FIG>) with the metal foil layer <NUM> preferably comprising one of, a titanium foil layer 40a, a titanium alloy foil layer 40b, a nickel foil layer 40c a nickel alloy foil layer 40d, a stainless steel foil layer 40e, a stainless steel alloy foil layer 40f, an aluminum foil layer <NUM>, an aluminum alloy foil layer <NUM>, a copper foil layer 40i, a copper alloy foil layer 40j, or another suitable metal foil layer <NUM>. More preferably, the metal foil layer <NUM> comprises the titanium foil layer 40a.

The forming <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise surface treating a surface <NUM> (see <FIG>) of the metal foil layer <NUM> (see <FIG>) with a surface treatment process <NUM> (see <FIG>), to obtain a treated surface 45a (see <FIG>), and priming the treated surface 45a of the metal foil layer <NUM> with a primer layer <NUM> (see <FIG>), prior to the polymer film layer <NUM> being laminated to the metal foil layer <NUM>, and prior to obtaining the formed laminated hybrid metallized polymer film <NUM>. One or more surfaces <NUM> (see <FIG>) of the metal foil layer <NUM>, for example, a second side 140b (see <FIG>) of the metal foil layer <NUM>, may be surface treated with one or more surface treatment processes <NUM> (see <FIG>), to obtain one or more treated surfaces 45a (see <FIG>), for example, to facilitate adhesion to a laminating adhesive layer <NUM> (see <FIG>) of the laminated hybrid metallized polymer film <NUM>. An example of a surface treatment process <NUM> that may be used includes a sol-gel process <NUM> (see <FIG>) to treat or prepare the metal foil layer <NUM>, such as a sol-gel process disclosed in <CIT>, <CIT>, and <CIT>. However, other types of surface treatment processes <NUM> may also be used to surface treat the metal foil layer <NUM> prior to undergoing a lamination process <NUM> (see <FIG>). In addition, the one or more treated surfaces 45a of the metal foil layer <NUM> may then be primed with a primer layer <NUM> (see <FIG>, <FIG>). The primer layer <NUM> is preferably applied with a primer application process <NUM> (see <FIG>).

In addition, the forming <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise processing or modifying the metal foil layer <NUM> prior to the polymer film layer <NUM> being laminated to the metal foil layer <NUM>, and prior to obtaining the formed laminated hybrid metallized polymer film <NUM>. The metal foil layer <NUM> may have various configurations <NUM> (see <FIG>). As shown in <FIG>, the metal foil layer <NUM> may have a configuration <NUM> comprising a plain metal foil 46a (see also <FIG>), which is not processed or modified before application to the surface <NUM> (see <FIG>), such as the substrate surface <NUM> (see <FIG>), of the composite structure <NUM> (see <FIG>). Alternatively, as shown in <FIG>, the metal foil layer <NUM> may be processed or modified and have a configuration <NUM> comprising one of, a slotted metal foil 46b (see also <FIG>), a perforated metal foil 46c (see also <FIG>), an expanded metal foil 46d (see also <FIG>), a mesh metal foil 46e (see also <FIG>), or another suitable configuration <NUM>.

The forming <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise forming the laminated hybrid metallized polymer film <NUM> with the laminating adhesive layer <NUM> (see <FIG>) comprising one of, a urethane adhesive layer 50a (see <FIG>) including a polyurethane adhesive layer 50b (see <FIG>), an epoxy adhesive layer 50c (see <FIG>), a polysiloxane adhesive layer 50d (see <FIG>), a silicone adhesive layer 50e (see <FIG>), an acrylic adhesive layer 50f (see <FIG>), or another suitable laminating adhesive layer <NUM>. The forming <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise forming the laminated hybrid metallized polymer film <NUM> with the polymer film layer <NUM> comprising one of, a polyether ether ketone (PEEK) film layer 60a, a polyester film layer 60b, a polyethylene terephthalate (PET) film layer 60c, a polypropylene (PP) film layer 60d, a polyethylene (PE) film layer 60e, a polytrimethylene terephthalate (PTT) film layer 60f, a polyamide (PA) film layer <NUM>, a polyetherimide (PEI) film layer <NUM>, a polyvinyl chloride (PVC) film layer 60i, a polycarbonate (PC) film layer 60j, a nylon film layer <NUM>, a polyetherketoneketone (PEKK) film layer <NUM>, a polyphenylsulfone (PPSU) film layer <NUM>, a polyphenylene sulfide (PPS) film layer 60n, an ethylene chlorotrifluoroethylene (ECTFE) film layer 60o, a polyvinylidene fluorine (PVDF) film layer 60p, or another suitable polymer film layer <NUM>.

The forming <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise forming the laminated hybrid metallized polymer film <NUM> with the adhesive layer <NUM> (see <FIG>) comprising one of, a sealant adhesive layer <NUM> (see <FIG>) including a polythioether sealant adhesive layer 72a (see <FIG>), a polysulfide sealant adhesive layer 72b (see <FIG>), or another suitable sealant adhesive layer <NUM>; a pressure sensitive adhesive (PSA) layer <NUM> (see <FIG>); a curable film adhesive layer <NUM> (see <FIG>) including a heat curable film adhesive layer 76a (see <FIG>), or another suitable adhesive layer <NUM>.

The laminated hybrid metallized polymer film <NUM> (see <FIG>) may be in the form <NUM> (see <FIG>) of a tape <NUM> (see <FIG>), including a tape roll 32a (see <FIG>), or a tape strip 32b (see <FIG>). Alternatively, the laminated hybrid metallized polymer film <NUM> may be the form <NUM> of an applique <NUM> (see <FIG>), a sheet <NUM> (see <FIG>), an overlay <NUM> (see <FIG>), or another suitable form <NUM>.

As shown in <FIG>, the method <NUM> further comprises the step of preparing <NUM> a substrate surface <NUM> (see <FIG>) of the composite structure <NUM> (see <FIG>), such as an aircraft composite structure <NUM> (see <FIG>), to obtain a prepared substrate surface 28a (see <FIG>). The preparing <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may comprise preparing <NUM> the substrate surface <NUM> of the composite structure <NUM> with one or more surface treatment processes <NUM> (see <FIG>), such as cleaning, smoothing, polishing, or another suitable surface treatment processes <NUM>. In addition, the preparing <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) may further comprise applying an edge seal layer <NUM> (see <FIG>) over the substrate surface <NUM>; applying a primer layer <NUM> (see <FIG>) over the substrate surface <NUM>; or applying the edge seal layer <NUM> over the substrate surface <NUM> and applying the primer layer <NUM> over the edge seal layer <NUM>. Alternatively, the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>) may be applied directed to the substrate surface <NUM>, such as the prepared substrate surface 28a, without the edge seal layer <NUM> (see <FIG>, <FIG>, <FIG>) and the primer layer <NUM> (see <FIG>, <FIG>, <FIG>).

As shown in <FIG>, the method <NUM> further comprises the step of applying <NUM> the laminated hybrid metallized polymer film <NUM> over and to the prepared substrate surface 28a (see <FIG>) of the composite structure <NUM> (see <FIG>), as the aircraft composite structure <NUM> (see <FIG>). The adhesive layer <NUM> adheres the polymer film layer <NUM> to the prepared substrate surface 28a. When the composite structure <NUM>, such as the aircraft composite structure <NUM>, is exposed to one or more erosion conditions <NUM> (see <FIG>), the laminated hybrid metallized polymer film <NUM> applied over and to the prepared substrate surface 28a provides erosion protection <NUM> (see <FIG>) to the composite structure <NUM> from the one or more erosion conditions <NUM>.

The applying <NUM> (see <FIG>) step of the method <NUM> (see <FIG>) further comprises applying the laminated hybrid metallized polymer film <NUM> over and to the prepared substrate surface 28a of the composite structure <NUM> comprising an aircraft composite structure <NUM> (see <FIG>), and further wherein when the aircraft composite structure <NUM> is exposed to one or more erosion conditions <NUM> (see <FIG>) including an airstream <NUM> (see <FIG>), for example, an external airstream 18a (see <FIG>), where the laminated hybrid metallized polymer film <NUM> is applied over and to the prepared substrate surface 28a to prevent or minimize delamination <NUM> (see <FIG>) of one or more cut edges 86b (see <FIG>) of the prepared substrate surface 28a and to provide erosion protection <NUM> of the aircraft composite structure <NUM> from the one or more erosion conditions <NUM> including the airstream <NUM>.

Now referring to <FIG> is an illustration of a flow diagram of an exemplary aircraft manufacturing and service method <NUM>, and <FIG> is an illustration of an exemplary block diagram of an aircraft <NUM>. Referring to <FIG>, versions of the disclosure may be described in the context of the aircraft manufacturing and service method <NUM> as shown in <FIG>, and the aircraft <NUM> as shown in <FIG>.

During pre-production, exemplary aircraft manufacturing and service method <NUM> may include specification and design <NUM> of the aircraft <NUM> and material procurement <NUM>. During manufacturing, component and subassembly manufacturing <NUM> and system integration <NUM> of the aircraft <NUM> takes place. Thereafter, the aircraft <NUM> may go through certification and delivery <NUM> in order to be placed in service <NUM>. While in service <NUM> by a customer, the aircraft <NUM> may be scheduled for routine maintenance and service <NUM> (which may also include modification, reconfiguration, refurbishment, and other suitable services).

Each of the processes of the aircraft manufacturing and service method <NUM> may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include, without limitation, any number of aircraft manufacturers and major-system subcontractors. A third party may include, without limitation, any number of vendors, subcontractors, and suppliers. An operator may include an airline, leasing company, military entity, service organization, and other suitable operators.

As shown in <FIG>, the aircraft <NUM> produced by the exemplary aircraft manufacturing and service method <NUM> may include an airframe <NUM> with a plurality of systems <NUM> and an interior <NUM>. Examples of the plurality of systems <NUM> may include one or more of a propulsion system <NUM>, an electrical system <NUM>, a hydraulic system <NUM>, and an environmental system <NUM>. Any number of other systems may be included. Although an aerospace example is shown, the principles of the disclosure may be applied to other industries, such as the automotive industry.

Methods and systems embodied herein may be employed during any one or more of the stages of the aircraft manufacturing and service method <NUM>. For example, components or subassemblies corresponding to component and subassembly manufacturing <NUM> may be fabricated or manufactured in a manner similar to components or subassemblies produced while the aircraft <NUM> is in service <NUM>. Also, one or more apparatus embodiments, method embodiments, or a combination thereof, may be utilized during component and subassembly manufacturing <NUM> and system integration <NUM>, for example, by substantially expediting assembly of or reducing the cost of the aircraft <NUM>. Similarly, one or more of apparatus embodiments, method embodiments, or a combination thereof, may be utilized while the aircraft <NUM> is in service <NUM>, for example and without limitation, to maintenance and service <NUM>.

Disclosed embodiments of the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>), the system <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>), and method <NUM> (see <FIG>) provide erosion protection <NUM> (see <FIG>) from one or more erosion conditions <NUM> (see <FIG>), for example, an airstream <NUM> (see <FIG>), such as an external airstream 18a (see <FIG>), to prevent or minimize delamination <NUM> (see <FIG>), of a composite structure <NUM> (see <FIG>), such as an aircraft composite structure <NUM> (see <FIG>). In particular, the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>) provides for erosion protection <NUM> of edges <NUM> (see <FIG>), such as leading edges 86a (see <FIG>), with cut edges 86b, of surfaces <NUM> (see <FIG>) of composite structures <NUM>. As discussed above, the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>) has a hybrid metal film portion <NUM> (see <FIG>) comprising a metal foil layer <NUM> (see <FIG>), such as a titanium foil layer 40a (see <FIG>), that is very thin and lightweight, laminated with a laminating adhesive layer <NUM> (see <FIG>), to a polymer film layer <NUM> (see <FIG>). As discussed above, the laminated hybrid metallized polymer film <NUM> further has a bonding adhesive portion <NUM> (see <FIG>) that adheres or bonds the hybrid metal film portion <NUM> to a substrate surface <NUM> (see <FIG>), such as a prepared substrate surface 28a (see <FIG>), of the composite structure <NUM>, such as the aircraft composite structure <NUM>. The hybrid metal film portion <NUM> may be applied to the substrate surface <NUM> of the composite structure <NUM>, such as the aircraft composite structure <NUM> using several options, including using a sealant adhesive layer <NUM> (see <FIG>), using a pressure sensitive adhesive (PSA) layer <NUM> (see <FIG>) similar to a peel-and-stick process, for example, an applique, or using a curable film adhesive layer <NUM> (see <FIG>), such as a heat curable film adhesive layer (see <FIG>).

Moreover, disclosed embodiments of the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>), the system <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>), and method <NUM> (see <FIG>) provide a laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>) or hybrid film product that is easy to handle, manipulate, cut, install, and apply to a surface <NUM> (see <FIG>), such as a substrate surface <NUM>, for example, a prepared substrate surface 28a (see <FIG>), and leading edges 86a (see <FIG>) and cut edges 86b (see <FIG>), of composite structures <NUM>, such as aircraft composite structures <NUM>, as compared to known thicker and heavier metal foil products applied to surfaces and leading edges of aircraft composite structures. Thus, the time required to handle, manipulate, cut, install, and apply the laminated hybrid metallized polymer film <NUM> onto the composite structures <NUM>, such as the aircraft composite structures <NUM>, may be reduced, as compared to such known metal foil products. The laminated hybrid metallized polymer film <NUM> preferably has improved handleability due to the flexibility of the polymer film layer <NUM> and the thinness and light weight of the metal foil layer <NUM> used, as compared to known thicker and heavier metal foil products applied to surfaces and leading edges of aircraft composite structures. Since the laminated hybrid metallized polymer film <NUM> has a thinner and lighter weight metal foil layer <NUM> that is easier to handle, with the polymer film layer <NUM> laminated to the metal foil layer <NUM>, the cost of manufacturing and maintaining the laminated hybrid metallized polymer film <NUM> for erosion protection <NUM> is decreased, as compared to thicker and heavier metal foil products.

In addition, disclosed embodiments of the laminated hybrid metallized polymer film <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>) may be more easily formed over curved surfaces <NUM> (see <FIG>) with complex curvature <NUM> (see <FIG>), for example, leading edges 86a (see <FIG>, <FIG>) of wing panels <NUM> (see <FIG>, <FIG>), barrel sections <NUM> (see <FIG>, <FIG>), passenger doors <NUM> (see <FIG>, <FIG>), access doors <NUM> (see <FIG>), window surrounds <NUM> (see <FIG>, <FIG>), horizontal stabilizers <NUM> (see <FIG>, <FIG>), and vertical stabilizers <NUM> (see <FIG>, <FIG>), of aircraft composite structures <NUM> (see <FIG>, <FIG>). Moreover, secondary processing to form the metal material <NUM>, such as titanium 44a, into a curved shape may no longer be needed.

Further, the laminated hybrid metallized polymer film <NUM> preferably maintains the excellent erosion capabilities and performance of the metal materials <NUM> (see <FIG>), and in particular, of titanium 44a (see <FIG>) and titanium alloy 44b, used for the metal foil layer <NUM>, and may greatly reduce possible rework by mitigating any possible damage that might occur to the metal foil layer <NUM>, prior to application on and to the composite structure <NUM>, such as the aircraft composite structure <NUM>. In particular, the metal foil layer <NUM>, such as the titanium foil layer 40a and the titanium alloy foil layer 40b, serve as effective means to provide erosion protection <NUM> to cut edges 86b (see <FIG>) of aircraft composite structures <NUM> (see <FIG>, <FIG>) that are exposed to one or more erosion conditions <NUM> (see <FIG>), such as an airstream <NUM> (see <FIG>), for example, an external airstream 18a (see <FIG>).

Claim 1:
A laminated hybrid metallized polymer film (<NUM>) for erosion protection (<NUM>) of a composite structure (<NUM>), the laminated hybrid metallized polymer film (<NUM>) comprising:
a metal foil layer (<NUM>), with a first side (140a) and a second side (140b);
a laminating adhesive layer (<NUM>), with a first side (142a) and a second side (142b), underlying the metal foil layer (<NUM>);
a polymer film layer (<NUM>), with a first side (144a) and a second side (144b), underlying the laminating adhesive layer (<NUM>),
the polymer film layer (<NUM>) laminated to the metal foil layer (<NUM>) with the laminating adhesive layer (<NUM>) coupled between the metal foil layer (<NUM>) and the polymer film layer (<NUM>); and
an adhesive layer (<NUM>), with a first side (146a) and a second side (146b), underlying the polymer film layer (<NUM>), the adhesive layer (<NUM>) adhering the polymer film layer (<NUM>) to a substrate surface (<NUM>) of the composite structure (<NUM>); wherein:
the first side (140a) of the metal foil layer (<NUM>) is exposed;
the second side (140b) of the metal foil layer (<NUM>) is adj acent to, and coupled or attached to, the first side (142a) of the laminating adhesive layer (<NUM>);
the second side (142b) of the laminating adhesive layer (<NUM>) is adjacent to, and coupled or attached to, the first side (144a) of the polymer film layer (<NUM>); and
the second side (144b) of the polymer film layer (<NUM>) is adjacent to, and coupled or attached to, the first side (146a) of the adhesive layer (<NUM>);
wherein the adhesive layer (<NUM>) has a thickness (<NUM>) in a range of from <NUM> inch (<NUM> millimeter) to <NUM> inch (<NUM> millimeter), and
wherein the metal foil layer (<NUM>), the laminating adhesive layer (<NUM>), the polymer film layer (<NUM>), and the adhesive layer (<NUM>) form the laminated hybrid metallized polymer film (<NUM>) for application over and to the substrate surface (<NUM>) of the composite structure (<NUM>).