Patent Description:
<CIT> states in its abstract that fire-retardant composites, methods of making fire-retardant composites, and use thereof are described therein. A fire-retardant composite can include two fire-retardant laminates, and a porous thermoplastic core material disposed between the two fire-retardant laminates. Each laminate can have one or more ply, each of the plies can include a plurality of fibers in a thermoplastic polymer matrix that includes a fire-retardant composition.

<CIT> states in its abstract that blends of polysulfones, polyethersulfones and polyphenylene ether sulfones with resorcinol based polyesters, or resorcinol based polyester carbonate polymers, and silicone copolymers have improved flame resistance. Peak heat release energy is reduced and the time to reach peak heat release is increased.

Accordingly, those skilled in the art continue with research and development efforts in the field of fire seals.

The present disclosure relates to a fire seal according to claim <NUM> and a fire sealing method according to claim <NUM>.

In one example, the disclosed fire seal includes an amorphous material and a bulk material supporting the amorphous material. The bulk material is fire resistant.

Also disclosed are multi-member assemblies.

In one example, the disclosed multi-member assembly includes a first structural member and a second structural member opposed from the first structural member. The multi-member assembly further includes a fire seal positioned between the first structural member (<NUM>) and the second structural member. The fire seal includes a bulk material and an amorphous material supported by the bulk material. The bulk material is fire resistant.

Also disclosed are fire-sealing methods.

In one example, the disclosed fire-sealing method includes positioning a fire seal between a first structural member and a second structural member. The fire seal includes a bulk material and an amorphous material supported by the bulk material. The bulk material is fire resistant.

Other examples of the disclosed fire seals and associated multi-member assemblies and fire-sealing methods will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

The following detailed description refers to the accompanying drawings, which illustrate specific examples described by the present disclosure. Other examples having different structures and operations do not depart from the scope of the present disclosure. Like reference numerals may refer to the same feature, element, or component in the different drawings.

Illustrative, non-exhaustive examples, which may be, but are not necessarily, claimed, of the subject matter according to the present disclosure are provided below. Reference herein to "example" means that one or more feature, structure, element, component, characteristic, and/or operational step described in connection with the example is included in at least one aspect, embodiment, and/or implementation of the subject matter according to the present disclosure. Thus, the phrases "an example," "another example," "one or more examples," and similar language throughout the present disclosure may, but do not necessarily, refer to the same example. Further, the subject matter characterizing any one example may, but does not necessarily, include the subject matter characterizing any other example. Moreover, the subject matter characterizing any one example may be, but is not necessarily, combined with the subject matter characterizing any other example.

For the purpose of this disclosure, the terms "coupled," "coupling," and similar terms refer to two or more elements that are joined, linked, fastened, attached, connected, put in communication, or otherwise associated (e.g., mechanically, electrically, fluidly, optically, electromagnetically) with one another. In various examples, the elements may be associated directly or indirectly. As an example, element A may be directly associated with element B. As another example, element A may be indirectly associated with element B, for example, via another element C. It will be understood that not all associations among the various disclosed elements are necessarily represented. Accordingly, couplings other than those depicted in the figures may also exist.

References throughout the present specification to features, advantages, or similar language used herein do not imply that all of the features and advantages that may be realized with the examples disclosed herein should be, or are in, any single example. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an example is included in at least one example. Thus, discussion of features, advantages, and similar language used throughout the present disclosure may, but do not necessarily, refer to the same example.

Referring to <FIG>, disclosed is a fire seal <NUM>. The fire seal <NUM> includes an amorphous material <NUM> (<FIG>) and a bulk material <NUM> (<FIG>) supporting the amorphous material <NUM>. In one example, the amorphous material <NUM> is layered with the bulk material <NUM>, see <FIG>. In another example, the amorphous material <NUM> is dispersed in the bulk material <NUM>, see <FIG> and <FIG>. In yet another example, the amorphous material <NUM> is embedded in the bulk material <NUM>.

The fire seal <NUM> may further include a nano-clay material <NUM> supported by the bulk material <NUM>, see <FIG> and <FIG>. The nano-clay material <NUM> may have an average particle size within a range from about <NUM> to about <NUM>, such as an average particle size within a range from about <NUM> to about <NUM>, or an average particle size within a range from about <NUM> to about <NUM>. The nano-clay material <NUM> may be incorporated as a single layer or multiple layers to increase the diffusion barrier. For example, a high tortuosity diffusion path in the fire seal <NUM> material due to the addition of nano-clay material <NUM> may reduce the oxygen diffusion rate. A multi-layer assembly including nano-clay material <NUM> may help achieve ultra-low diffusion coefficients in the fire seal <NUM>.

In addition to nano-clay material <NUM>, in one or more examples, the fire seal <NUM> may include one or more additives to promote, among other things, CO<NUM> evolution beyond specific temperature thresholds. Examples include carbonates (e.g., calcium carbonate and/or sodium carbonate), bicarbonates (e.g., sodium bicarbonate), glucose, citrates, and the like, and mixtures thereof.

The fire seal <NUM> may also include other additives. Examples of other additives include, but are not limited to, silica, alumina, zirconia, graphene, graphene oxide, graphite oxide, and the like, and mixtures thereof, which may be supported by the bulk material <NUM>.

Referring to <FIG>, in one or more examples, the fire seal <NUM> may include an infrared-reflective coating <NUM> on an outside surface <NUM> of the fire seal <NUM>. The infrared-reflective coating <NUM> may include inclusions that limit heat absorption in the material. The infrared-reflective coating <NUM> may include, for example, infrared-reflective pigments (e.g., leafing aluminum flakes) in a binder (e.g., thermoset resin).

The amorphous material <NUM> may include any material having requisite material properties for the fire seal <NUM>, specifically related to self-healing of one or more crack or defect <NUM> that may manifest after exposure to high temperatures. In one example, the amorphous material <NUM> includes a glass material. In another example, the amorphous material <NUM> includes a glass powder material. In a non-limiting example, the amorphous material <NUM> includes a vanadate glass material. In another example, the amorphous material <NUM> includes a sponge material. In another example, the amorphous material <NUM> includes a fiber material. In yet another example, the amorphous material <NUM> includes a combination or mixture of materials.

The amorphous material <NUM> has a glass transition temperature Tg. In one example, the glass transition temperature Tg is between approximately <NUM> and approximately <NUM>. In another example, the glass transition temperature Tg is between approximately <NUM> and approximately <NUM>. Upon reaching the glass transition temperature Tg, the amorphous material <NUM> may become a flowy amorphous material <NUM>', see <FIG>, and can thus flow into one or more crack or defect <NUM> of the fire seal <NUM>.

The bulk material <NUM> is fire resistant. The bulk material <NUM> decomposes at a decomposition temperature TD. In one example, the decomposition temperature TD is at least <NUM>. In another example, the decomposition temperature TD is at least <NUM>. In yet another example, the decomposition temperature TD is at least <NUM>. The decomposition temperature TD may be different than the glass transition temperature Tg. In one or more examples, a difference between the glass transition temperature Tg and the decomposition temperature TD is at least <NUM>. In another example, a difference between the glass transition temperature Tg and the decomposition temperature TD is at least <NUM>.

The bulk material <NUM> may include any material having requisite material properties for the fire seal <NUM>. In one example, the bulk material <NUM> includes a ceramic material. In one specific example, the bulk material <NUM> includes ceramic oxide fibers. In another example, the bulk material <NUM> includes a polymeric material. For example, the bulk material <NUM> may include aramid fibers, such as, for example, para-aramid material (e.g., KEVLAR brand fibers commercially available from DuPont) and/or a meta-aramid material (e.g., NOMEX brand fibers/sheets commercially available from DuPont). In another example, the bulk material <NUM> may include ceramic oxide fibers.

Further, the bulk material <NUM> may include one or more of a fabric material, a foam material, and a felt material. Examples of a fabric material include Nextel™ (AF-<NUM>, AF-<NUM>-<NUM>) (trademarks of <NUM>™), Nomex® (HT-<NUM>, HT001) (trademarks of Dupont™), Dacron™ (trademark of Dupont™), Kevlar™ (trademark of Dupont™), S2, and E-glass.

Referring to <FIG>, in one or more examples, the fire seal <NUM> includes a coating on an outside surface of the fiber material. In one example, the coating includes a polymer material. In another example, the coating includes a second amorphous material <NUM> having a second glass transition temperature Tg2. The glass transition temperature Tg and the second glass transition temperature Tg2 may be different. In one example, a difference between the glass transition temperature Tg and the second glass transition temperature Tg2 is at least <NUM>. In another example, a difference between the glass transition temperature Tg and the second glass transition temperature Tg2 is at least <NUM>.

Referring to <FIG>, in one or more examples, the amorphous material <NUM> includes a plurality of glass fibers <NUM>. In one example, the plurality of glass fibers <NUM> is braided together. In another example, the plurality of glass fibers <NUM> is woven together. The plurality of glass fibers may include a first fiber <NUM> having a first glass transition temperature Tfg1 and a second fiber <NUM> having a second glass transition temperature Tfg2. In one example, the first fiber <NUM> and the second fiber <NUM> are glass.

In one example, a difference between the first glass transition temperature Tfg1 of the first fiber <NUM> and the second glass transition temperature Tfg2 of the second fiber <NUM> is at least <NUM>. In another example, a difference between of the first fiber and the second glass transition temperature Tfg2 of the second fiber is at least <NUM>.

Still referring to <FIG>, in one or more examples, the amorphous material <NUM> includes a first fiber <NUM> having a core material <NUM> and a glass coating <NUM> on an outside surface of the core material <NUM>, see <FIG>. The glass coating <NUM> has a coating glass transition temperature Tcg. The amorphous material <NUM> may further include a second fiber <NUM> entwined with the first fiber <NUM>. The second fiber <NUM> has a second core material <NUM> and a second coating <NUM> on an outside surface of the second core material <NUM>, see <FIG>. The second coating <NUM> has a second coating <NUM> glass transition temperature Tcg2.

In one example, the core material <NUM> of the first fiber <NUM> and the second core material <NUM> of the second fiber <NUM> are compositionally different and may further have different glass transition temperatures. In one example, the core material <NUM> of the first fiber <NUM> comprises an amorphous material <NUM> having a core glass transition temperature Tgc and a difference between the core glass transition temperature Tgc and the coating glass transition temperature Tcg is at least <NUM>.

Further, a difference between the coating glass transition temperature Tcg and the second coating <NUM> glass transition temperature Tcg2 may be at least <NUM>. In another example, a difference between the coating glass transition temperature Tcg and the second coating <NUM> glass transition temperature Tcg2 is at least <NUM>.

In one example, the core material <NUM> of the first fiber <NUM> includes an amorphous material <NUM> having a core glass transition temperature Tgc and a difference between the core glass transition temperature Tgc and the coating glass transition temperature Tcg is at least <NUM>.

The core material <NUM> may include and material having requisite material properties for the fire seal <NUM>. In another example, the core material <NUM> of the first fiber <NUM> includes a polymeric material. In yet another example, the core material <NUM> of the first fiber <NUM> includes an aramid polymer. In one specific example, the core material <NUM> of the first fiber <NUM> includes Kevlar™.

In one or more examples, the second core material <NUM> of the second fiber <NUM>, see <FIG> and <FIG>, includes an amorphous material <NUM>. The second core material <NUM> of the second fiber <NUM> has a second core glass transition temperature Tgc2. In one example, a difference between the second core glass transition temperature Tgcs and the second coating <NUM> glass transition temperature Tcg2 is at least <NUM>. In another example, a difference between the second core glass transition temperature Tgc2 and the second coating <NUM> glass transition temperature Tcg2 is at least <NUM>.

The second core material <NUM> may include and material having requisite material properties for the fire seal <NUM>. In one example, the second core material <NUM> of the second fiber <NUM> includes a polymeric material. In another example, the second core material <NUM> of the second fiber <NUM> includes an aramid polymer. In one specific example, the second core material <NUM> of the second fiber <NUM> includes Kevlar™.

Referring to <FIG>, disclosed is a multi-member assembly <NUM>. The multi-member assembly <NUM> includes a first structural member <NUM> and a second structural member <NUM> opposed from the first structural member <NUM>. The multi-member assembly <NUM> further includes a fire seal <NUM> positioned between the first structural member <NUM> and the second structural member <NUM>. In one example, the first structural member <NUM> is an engine and the second structural member <NUM> is a pylon.

The fire seal <NUM> of the multi-member assembly <NUM> includes a bulk material <NUM>. In one example, the bulk material <NUM> is fire resistant. The fire seal <NUM> of the multi-member assembly <NUM> further includes an amorphous material <NUM> supported by the bulk material <NUM>. Further, in one or more examples, the fire seal <NUM> of the multi-member assembly <NUM> may include an infrared-reflective coating <NUM> on an outside surface <NUM> of the fire seal <NUM>.

Also disclosed is a fire sealing method. The fire sealing method includes the step of positioning a fire seal <NUM> between a first structural member <NUM> and a second structural member <NUM>. The fire seal <NUM> includes a bulk material <NUM>. In one example, the bulk material <NUM> is fire resistant. The fire seal <NUM> further includes an amorphous material <NUM> supported by the bulk material <NUM>. Further, in one or more examples, the fire seal <NUM> of the fire sealing method may include an infrared-reflective coating <NUM> on an outside surface of the fire seal <NUM>.

The fire sealing method may be performed on aircraft components. In one example, the first structural member <NUM> of the fire-sealing method is an engine of an aircraft and the second structural member <NUM> of the fire-sealing method is a pylon of the aircraft.

Glass sealants or fire seals <NUM> incorporating glass fabric or chopped fiber can be used to hermetically seal interfaces between the different structural members <NUM>, <NUM> of a multi-member assembly <NUM>. Glass has excellent high temperature stability and its ability to soften at high temperature and set again when it cools down provides self-healing capability for the seals subjected to high temperature. If a fire seal <NUM> develops one or more crack and/or defect <NUM> due to exposure to very high temperature, the glass can flow and fill such defect <NUM>, see <FIG>.

The amorphous material <NUM> may be incorporated into a fire seal <NUM> as a glass fiber layer within the seal architecture, see <FIG>, or as chopped fiber glass dispersed in the matrix material or bulk material <NUM>, see <FIG>. As either a fabric or chopped fiber, tubular, ribbons, fiber bundles, dispersed strands, etc., glass encompasses adequate flexibility to be incorporated into complex seal geometries without damage or brittle failure. Various glass compositions may be utilized to meet requirements for various service temperatures. Glass is a highly inert material and thus can be easily incorporated with a vast range of fire seal <NUM> materials, particularly in the aerospace industry.

The fire seal <NUM> as shown and described herein may utilize an amorphous material <NUM> having multilayer glass-fiber expanded weave structure impregnated within a matrix resin bulk material <NUM>. The amorphous material <NUM> provides the fire seal <NUM> with a range of protection at different temperature levels for progressive softening, melting etc. The amorphous material <NUM> further helps retain mechanical properties when temperature is continuously increasing in the fire seal <NUM>. The fire seal <NUM> may include two or more families of coated glass fibers having different glass transition and melting temperatures such that one begins to transition at a lower temperature than the other. As one glass fiber melts, it spreads and helps heal defect <NUM> regions in the fire seal <NUM>. The other glass fiber having a higher melting and glass transition temperature concurrently continues to provide overall strength. Alternative materials may be implemented in the structures shown and described herein including glass coated silica, Kevlar™ etc., to provide the beneficial material properties of glass along with the structural properties of silica or Kevlar™. For example, multiple Kevlar™ fibers coated with various glass chemistries weaved together may progressively contribute to softening, melting, sealing, healing steps.

Examples of the subject matter disclosed herein may be described in the context of aircraft manufacturing and service method <NUM> as shown in <FIG> and aircraft <NUM> as shown in <FIG>. During pre-production, service method <NUM> may include specification and design (block <NUM>) of aircraft <NUM> and material procurement (block <NUM>). During production, component and subassembly manufacturing (block <NUM>) and system integration (block <NUM>) of aircraft <NUM> may take place. Thereafter, aircraft <NUM> may go through certification and delivery (block <NUM>) to be placed in service (block <NUM>). While in service, aircraft <NUM> may be scheduled for routine maintenance and service (block <NUM>). Routine maintenance and service may include modification, reconfiguration, refurbishment, etc. of one or more systems of aircraft <NUM>.

Each of the processes of 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; and an operator may be an airline, leasing company, military entity, service organization, and so on.

As shown in <FIG>, aircraft <NUM> produced by service method <NUM> may include airframe <NUM> with a plurality of high-level systems <NUM> and interior <NUM>. Examples of high-level systems <NUM> include one or more of propulsion system <NUM>, electrical system <NUM>, hydraulic system <NUM>, and environmental system <NUM>. Any number of other systems may be included. Although an aerospace example is shown, the principles disclosed herein may be applied to other industries, such as the automotive industry. Accordingly, in addition to aircraft <NUM>, the principles disclosed herein may apply to other vehicles, e.g., land vehicles, marine vehicles, space vehicles, etc..

The disclosed fire seals and fire-sealing methods shown or described herein may be employed during any one or more of the stages of the manufacturing and service method <NUM>. For example, components or subassemblies corresponding to component and subassembly manufacturing (block <NUM>) may be fabricated or manufactured in a manner similar to components or subassemblies produced while aircraft <NUM> is in service (block <NUM>). Also, one or more examples of the systems, methods, or combination thereof may be utilized during production stages component and subassembly manufacturing (block <NUM>) and system integration (block <NUM>), for example, by substantially expediting assembly of or reducing the cost of aircraft <NUM>. Similarly, one or more examples of the systems or method realizations, or a combination thereof, may be utilized, for example and without limitation, while aircraft <NUM> is in service (block <NUM>) and/or during maintenance and service (block <NUM>).

The fire seals and fire-sealing methods are described in the context of an aircraft. However, one of ordinary skill in the art will readily recognize that the disclosed fire seals and fire-sealing methods may be utilized for a variety of applications. For example, the disclosed fire seals and fire-sealing methods may be implemented in various types of vehicles including, e.g., helicopters, watercraft, passenger ships, automobiles, various materials processing equipment design, and the like.

Further, the disclosure comprises the following illustrative examples:
According to a first illustrative example, a fire seal (<NUM>) comprises: an amorphous material (<NUM>); and a bulk material (<NUM>) supporting the amorphous material, wherein the bulk material (<NUM>) is fire resistant.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) has a glass transition temperature (Tg), and wherein the glass transition temperature (Tg) is between approximately <NUM> and approximately <NUM>.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) has a glass transition temperature (Tg) and the bulk material (<NUM>) has a decomposition temperature (TD), and wherein a difference between the glass transition temperature (Tg) and the decomposition temperature (TD) is at least <NUM>, preferably wherein:
a difference between the glass transition temperature (Tg) and the decomposition temperature (TD) is at least <NUM>.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) comprises a glass material.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) comprises a glass powder material.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) comprises a vanadate glass material.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) comprises a sponge material.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) comprises a fiber material, preferably wherein the fire seal further comprises:. a coating (<NUM>) on an outside surface (<NUM>) of the fiber material, preferably wherein:.

Optionally, in the fire seal of the first illustrative example, the amorphous material comprises a plurality of glass fibers (<NUM>), preferably wherein:.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) comprises: a first fiber (<NUM>) having a core material (<NUM>) and a glass coating (<NUM>) on an outside surface of the core material, the glass coating (<NUM>) having a coating glass transition temperature (Tcg); and a second fiber (<NUM>) entwined with the first fiber (<NUM>) having a second core material (<NUM>) and a second coating (<NUM>) on an outside surface of the second core material (<NUM>), the second coating (<NUM>) having a second coating glass transition temperature (Tcg2), preferably wherein:.

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) is layered with the bulk material (<NUM>).

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) is dispersed in the bulk material (<NUM>).

Optionally, in the fire seal of the first illustrative example, the amorphous material (<NUM>) is embedded in the bulk material (<NUM>).

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) decomposes at a decomposition temperature (TD), and wherein the decomposition temperature (TD) is at least <NUM>.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises a ceramic material.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises a polymeric material.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises an aramid polymer, preferably wherein:
the aramid polymer comprises a meta-aramid polymer.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises ceramic oxide fibers.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises an amorphous material.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises a fabric material.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises a foam material.

Optionally, in the fire seal of the first illustrative example, the bulk material (<NUM>) comprises a felt material.

Optionally, the fire seal of the first illustrative example further comprises a nano-clay material (<NUM>) supported by the bulk material (<NUM>).

Optionally, the fire seal of the first illustrative example further comprises one or more of silica, alumina, zirconia, graphene, graphene oxide, and graphite oxide supported by the bulk material (<NUM>).

Optionally, the fire seal of the first illustrative example further comprises an infrared-reflective coating (<NUM>) on an outside surface (<NUM>) of the fire seal (<NUM>).

According to a second illustrative example, a multi-member assembly (<NUM>) comprises: a first structural member (<NUM>); a second structural member (<NUM>) opposed from the first structural member (<NUM>); and a fire seal (<NUM>) positioned between the first structural member (<NUM>) and the second structural member (<NUM>), the fire seal (<NUM>) comprising: a bulk material (<NUM>); and an amorphous material (<NUM>) supported by the bulk material (<NUM>), wherein the bulk material (<NUM>) is fire resistant.

Optionally, in the multi-member assembly of the second illustrative example, the first structural member (<NUM>) is an engine and wherein the second structural (<NUM>) member is a pylon.

According to a third illustrative example, a fire sealing method comprises: positioning a fire seal (<NUM>) between a first structural member (<NUM>) and a second structural member (<NUM>), the fire seal (<NUM>) comprising: a bulk material (<NUM>); and an amorphous material (<NUM>) supported by the bulk material (<NUM>), wherein the bulk material (<NUM>) is fire resistant.

Optionally, in the method of the third illustrative example, the first structural member (<NUM>) is an engine of an aircraft.

Optionally, in the method of the third illustrative example, the first structural member (<NUM>) is an engine of an aircraft and wherein the second structural member (<NUM>) is a pylon of the aircraft.

Claim 1:
A fire seal (<NUM>) comprising:
an amorphous material (<NUM>); and
a bulk material (<NUM>) supporting the amorphous material, wherein the bulk material (<NUM>) is fire resistant, wherein:
the amorphous material (<NUM>) comprises a fiber material, and a coating (<NUM>) on an outside surface (<NUM>) of the fiber material, wherein the coating (<NUM>) comprises a second amorphous material (<NUM>) having a second glass transition temperature (Tg2); and/or
the amorphous material comprises a plurality of glass fibers (<NUM>), comprising a first fiber (<NUM>) having a first glass transition temperature (Tfg1), and a second fiber (<NUM>) having a second glass transition temperature (Tfg2).