A method of manufacturing sheeting is provided, the method including the steps of forming multiple recesses in a symmetrical repeat pattern on a sheet of material, extruding a molten material to form an upper outside wall and a lower outside wall, interposing the formed sheet between the upper outside wall and the lower outside wall, and fixing the interposed sheet to the upper outside wall and the lower outside wall. Also provided is sheeting having an upper outside wall and a lower outside wall and an interposed sheet fixed between the outside walls. The interposed sheet includes multiple recesses in a symmetrical repeat pattern, where the upper and lower outside walls are, or the interposed sheet is, manufactured from a material which includes a polymeric material.

A method of applying an adhesive to a non-planar surface. The method includes providing a segmented film adhesive. The segmented film adhesive comprises: (i) a liner; and (ii) an adhesive layer on the liner, the adhesive layer comprising a plurality of contiguous, discrete adhesive segments. The segmented film adhesive is positioned on a non-planar surface of a first adherend so that a first portion of the discrete adhesive segments are in contact with the non-planar surface and a second portion of the discrete adhesive segments are not in contact with the non-planar surface. The liner is removed from the non-planar surface, wherein only the first portion of the discrete adhesive segments remain on the non-planar surface of the first adherend.

A material can have a layered structure with at least a first layer, including a carbon-based material or a substrate of a material other than a carbon-based material, a second layer, including a carbon-based material, and a third, intermediate layer that separates and interconnects the first and second layers. The carbon-based material includes at least 50 at. % carbon, has a hexagonal lattice and the layer or layers including the carbon-based material has/have a thickness of 1-20 times the size of a carbon atom. The intermediate layer is a layer that includes a salt having ions that include at least two separate cyclic, planar groups that are capable of forming π-π-stacking with the material of the second layer and that the third, intermediate layer is connected to at least the second layer by π-π-stacking caused by said cyclic planar groups of the salt ions.

In one aspect, there is a composite skin for a tiltrotor aircraft including a first skin having a periphery defined by a forward edge, an aft edge, and outboard ends; a second skin; and a honeycomb core disposed between the first skin and the second skin, the honeycomb core comprised of a plurality of honeycomb panels positioned along the longitudinal axis of the first skin, the plurality of honeycomb panels having an array of large cells, each cell having a width of at least 1 cm; wherein the second skin and the honeycomb core have an outer perimeter within the periphery of the first skin.

A composite sandwich panel assembly including an open area core, a high gloss surface sheet, and a structural skin. The open are core defines a plurality of pores and has a first face and an opposing second face. The high gloss surface sheet is adhered to the first face of the open area core by a first adhesive layer. The high gloss surface sheet has a high gloss surface. The structural skin is adhered to the second face of the open area core by a second adhesive layer. A process for forming the composite sandwich panel assembly includes positioning the high gloss surface sheet, joining the first face of the open area core to the high gloss surface sheet with a first adhesive layer intermediate therebetween, and joining the structural skin to the second face of the open area core with a second adhesive layer intermediate therebetween.

Various embodiments relate to an electromagnetic wave absorber having a honeycomb sandwich structure, which is capable of absorbing broadband electromagnetic waves using electromagnetic properties of a metal-coated dielectric fiber, may comprise: at least two honeycomb core layers in each of which hexagonal units formed of a material comprising the metal-coated dielectric fiber are continuously arranged; and skin layers which are disposed on top surfaces and bottom surfaces of the at least two honeycomb core layers and each include a bottom layer, a top layer, and an intermediate layer. Various other embodiments are possible.

A method of repairing a core stiffened structure, including removing a damaged portion of the core stiffened structure; bonding a shelf onto a first core member; bonding a second core member to a shelf; and securing a skin patch over the second core member.

A method for manufacturing a sandwich component includes applying at least one matrix material to the upper side and/or the underside of at least one material blank, and arranging the material blanks above one another and/or next to one another. At least two of the material blanks differ in design or matrix material may be applied in different ways along the upper side and/or underside thereof, or matrix material is applied in different ways to at least one of the material blanks along the upper side and/or underside thereof. In that way, at least one horizontal and/or vertical zone of the sandwich component is created having different mechanical properties than other regions of the sandwich component. The material blanks are then pressed to form the sandwich component.

A method of making an aircraft acoustic structural panel (10) begins with preforming a core honeycomb laminate (12) having preformed foam (3) bonded inside cells (14) thereof by a distinct adhesive (2). The preformed honeycomb laminate (12) is then stacked between opposite top and bottom structural outer laminates (16,18). The stacked honeycomb laminate (12) and outer structural laminates (16,18) are then compressed together under heat and pressure into a unitary structural panel (10) having the core honeycomb laminate (12) integrally bonded between outer skins (20,22). The outer laminates (16,18) may include imperforate acoustic septums (4) bounding the core honeycomb laminate (12) followed by an outer honeycomb (5) and structural fiber layers (6, 7, 8) defining the outer skins (20,22).

A protective fabric jacket for placement on an object to be protected from excessive heat includes a first layer; a second layer; and an intermediate spacer fabric layer that is disposed between the first layer and the second layer. The first and second layers are attached to the intermediate spacer fabric layer to form a layered structure. The intermediate spacer fabric layer comprises a flexible honeycomb or octagonal shaped spacer fabric that has a plurality of cells defined therein. The protective fabric jacket also includes a settable material that disposed within the cells and includes a cementitious mixture and one or more organic polymers and is settable to a hardened material.