A method of accelerating the reduction of residual stress in a bonded structure is provided. The method can include: providing a bonded structure having at least two substructures, wherein the substructures are bonded together with an adhesive; and submitting the bonded structure to a high-humidity environment having a relative humidity of at least 75%. The method can also include a step of submitting the bonded structure to an low-humidity environment having a relative humidity of at most 20%. According to the method, the bonded structure can have a first residual stress at a first time and a second residual stress at a second time, wherein an absolute value of the first residual stress is greater than an absolute value of the second residual stress. According to the method, the residual stress at the second time can be about zero.

Insulated paper products are disclosed. Methods of making and using insulated paper products are also disclosed.

An acoustic panel for an aircraft providing noise attenuation over a wide frequency band by combining two resonators, and acoustic panel manufacturing method. The acoustic panel includes a rear skin, a cellular structure, an intermediate layer including perforations, a cellular structure, a cellular structure and a resistive skin including perforations. The acoustic panel combines quarter-wave resonators with Helmholtz resonators to provide noise attenuation over a wide frequency range.

Disclosed herein is a molded laminated structure having negative draft angles and methods of manufacturing a molded laminated structure having negative draft angles. A preliminary structure having a first outer layer and a second outer layer is molded with a bend that divides the preliminary structure into two sections with an angle between the two sections of less than 180-degrees. Portions that extends from the sections are at positive draft angles. A groove is formed in the preliminary structure at the bend but not formed in a constant cross-section of the second outer layer. The preliminary structure is folding along the bend to at least partially close the groove and form a molded laminated structure with portions that extend at a negative draft configuration while retaining the second outer layer continuous throughout the molded laminated structure.

A core structure (300) for a composite panel for an aircraft, for example a door fairing for a landing gear bay, including a sandwich structure in which core cells (301) are sandwiched between first and second body sides (skins 303, 305). The core cells are square or rectangular in shape and each have a void formed by cell walls (307). The first and second body sides and the cell walls include laminated composite material of multiple layers. Drainage holes (320) in the cell walls form one or more direct drainage paths (P2, P3) for the flow of fluid from the core structure. The core cells include first and second sheets of cells reversibly mounted to each other, such that the void of each cell is formed in part by the first sheet and in part by the second sheet.

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.

The object of the invention can be a method of manufacturing a product in the form of a sandwich comprising a core and outer layers. The outer layers may be composed of composite material comprising a fiber-reinforced polymeric matrix. The method uses an insert of heat-resistant material, for example silicone. The object of this invention can be to provide a method of manufacturing a sandwich that dissociates the choice of material of the core of the sandwich from the choice of the material of the outer layers.

Load-bearing composite panels, materials, and products made by surrounding with a long fiber and/or fiber cloth reinforced polyurethane resin, an assembly containing one or more load-bearing members, graphene, a structural polyurethane/resin sandwich composite and/or spider silk protein fiber-cloth-continuous fibers. The composite structures can provide stronger, lighter-weight structural items such as vehicle floor and body panels, bullet-proof anti-ballistic panel products, vehicle bullet-proof anti-ballistic body panel structures and floors, bullet-proof vests, vehicle chassis, monocoque chassis, motor homes chassis-bodies, fuselage floors and frames for aircraft and/or UAV's, bicycle and motorcycle frames, wind turbine blades frames and structures, ship or boat haul body structures, shipment containers, pre-fabricated walls of buildings, train structure body or floor panels, solar panel supports, battery housings, mobile home walls, roof modules, truck beds, and truck trailer floors. Such composite panels, materials, and products can also be utilized in artificial organs, ligaments or tendons, artificial disc vertebrae, ropes, and 3D printing parts.

A heated floor panel assembly for aircraft includes an impact layer made from a 2-D or 3-D woven high temperature thermoplastic fiber matrix impregnated with a resin. The impact layer can further include woven metallic fibers. The assembly also includes a stack of structural layers, a heating layer, and a core layer for absorbing shear stress.

Disclosed are laminates comprising a carbon fiber reinforced polymer sheet and a layer of polysilazane and methods for producing such laminates.