Methods for machining a composite material substrate are discloses comprising integrating a predetermined pattern area having a disbond material for the purpose of creating a disbond region into the composite material substrate at a predetermined thickness, detecting the disbond region and forming a plurality of recesses in the composite material substrate by removing a machined plug from the composite material substrate to form recesses positioned at locations corresponding to the predetermined pattern area, and composite components comprising the recesses machined according to such methods.

A hierarchical sandwich core and a method of making it where a macroscopic honeycomb with a first macroscopic cell with first sandwich cell walls is connected to neighbouring macroscopic cells with neighbouring sandwich cell walls. The first and neighbouring sandwich cell walls are made of a sandwich material having a width, a mesoscopic core, and a first skin layer on a first major surface and a second skin layer on a second major surface of the sandwich material, both skin layers being attached to the mesoscopic core forming each sandwich cell wall of the macroscopic honeycomb. The first and the neighbouring cell walls have a height determined by the width of the sandwich material, both skin layers of the first sandwich cell wall being connected to both skin layers of at least one neighbouring cell wall along the height of the first cell wall.

A honeycomb core construction that includes at least two honeycomb cores and a connection layer that is disposed between the honeycomb cores. The connection layer is configured so as to be gas-permeable, and has an adhesive for adhesively bonding to the honeycomb cores only in a region of the webs of the honeycomb cores.

A unitary core panel for a composite sandwich structure includes a plurality of cell walls defining a plurality of core cells, the plurality of cell walls extending across a thickness of the core, the plurality of core cells including one or more defined structural nonuniformities resulting in nonuniform properties of the core panel. A method of forming a core panel for a composite sandwich structure includes determining structural requirements of the core panel, designing the core panel to satisfy the structural requirements with one or more local nonuniformities in the core panel, and manufacturing the core panel as a unitary core panel with the one or more local nonuniformities.

A reduced vibration structure comprises honeycomb and a vibration damping coating on at least a portion of the internal surface of at least a portion of the cells of the honeycomb. The vibration damping coating is formed by curing a coating composition comprising acrylic polymer or copolymer emulsion and a vibration damping filler. The structure can include an adhesive coupled to both the upper surface and the lower surface of the honeycomb and two pieces of sheathing coupled to the adhesive, one on the upper surface and one on the lower surface of the honeycomb.

Core structures for composite panels, aircraft including the same, and related methods. A core structure includes a core body defining a first body side, a second body side, and a plurality of core cells. Each core cell includes at least one cell wall and defines a tubular cell void. Each core cell includes a bulk region and a transition region. Each cell wall is flared within the transition region to increase a surface area of the first body side relative to an average transverse cross-sectional area of the core body. A composite panel includes a core structure with at least one laminate ply coupled to the first body side of a core body. A method of manufacturing a composite panel includes forming a core body via an additive manufacturing process and operatively attaching at least one laminate ply to the core body.

A fiber-reinforced resin composite includes a honeycomb core, a fiber-reinforced resin layer, and a protection layer. The honeycomb core includes a plurality of cells that are defined by partition walls and extend in an axial direction. The fiber-reinforced resin layer is disposed around the honeycomb core. The fiber-reinforced resin layer includes continuous fibers wound around the honeycomb core. The protection layer is interposed between the honeycomb core and the fiber-reinforced resin layer. The protection layer is configured to prevent rupture of the continuous fibers.

Some embodiments provide a core member for a composite panel that includes a hollow cell network structure, such as a honeycomb arrangement for example, and reinforced plastic strips positioned on a portion of the continuous honeycomb structure. The honeycomb structure and the solid plastic strips may be fastened together using heat and/or pressure applications. Additionally, the method for the production of the core member is provided.

Described are novel composite structural panels and methods of forming such panels. In some examples, a method comprises wrapping a mandrel with a composite tape to form a composite tube. This wrapping operation allows forming composite tubular structures with any cross-sectional profiles defined by the mandrel. The wrapping is also used to control the fiber orientations in the composite tubular structures. The composite tube is then cut into composite tubular structures. In some examples, the composite tube is partially cured prior to the cutting, which allows removal of the mandrel while preserving the shape of the composite tube. This cutting operation allows forming composite tubular structures with different lengths, shapes, and orientations of the ends. The composite tubular structures are disposed on a support structure and are bonded to each other. In some examples, this bonding operation also involves final curing of the composite tubular structures.

A component, including a part, comprising a honeycomb-like structure formed from at least a seamless resin-infused fiber composite material. The honeycomb-like structure includes a first plurality of cells, and a second plurality of cells, different than the first plurality of cells.