Methods and related structures to splice two sizes of cores in a manner to directly interface the facets of the cells and avoid the common practice of using fillers, casting materials, and expanding adhesives is useful to optimize the specific strength of the design and minimize the weight while maximizing the load carrying capability of the structure and to allow the core to vent moisture and other gasses.

A method of producing a cellular structure via an additive manufacturing technique includes the steps of: providing a feedstock material to an additive manufacturing printer device; dispensing the feedstock material from the printer device; and controlling the dispensing of the feedstock material to form at least one layer of the cellular structure according to a first predetermined gradient. In some aspects, the cellular structure comprises an array of cells surrounded, respectively, by walls, and arranged to create a non-uniform relative density and/or cell geometry across a width and/or a height of the cellular structure. An article of manufacture produced by such methods includes a cellular structure configured to produce a controlled collapse with selectable dynamic stiffness characteristics by altering the distribution and geometry of cells within the cellular structure, while being able to maintain a substantially similar static stiffness characteristic.

Apparatus and methods for sealing powder holes in additively manufactured parts are presented herein. Powder holes are co-printed to facilitate post processing sealing. Embodiments include co-printed caps, friction welded caps, rivets, silicone plugs, co-printed tangs, multiple micro holes, layup, and spin forming. By using one or more of the above techniques, powder holes can be sealed on additively manufactured parts.

Systems and method for fabricating a metal core truss panel with seamlessly embedded features in accordance with embodiments of the invention are illustrated. One embodiment includes a method for producing a metal core truss panel composite, the method including fabricating a sacrificial core truss panel including a plurality of interconnected truss members and at least one embedded feature, and plating the sacrificial core truss panel with a layer of metal forming a metal core truss panel including a plurality of interconnected metal truss members and at least one seamlessly embedded metal feature.

The present invention provides a self-adhesive prepreg which is characterized by comprising: a base prepreg that is composed of reinforcing fibers and a thermosetting resin composition (I), some or all of which is impregnated into a reinforcing fiber layer that is formed of the reinforcing fibers; an adhesive layer that is composed of a nonwoven fabric which is laminated on at least one surface of the base prepreg so as to be integrated with the base prepreg and a thermosetting resin composition (II) which is laminated on the surface of the nonwoven fabric so as to be integrated with the nonwoven fabric.

A method of fabricating a filler body for a blade of a rotor. In addition, such a method comprises a succession of steps of adding material layer by layer, each step consisting in making a new layer of material on a preceding layer of material made in the preceding step, at least one of the steps consisting in making an openwork layer of material presenting a plurality of openings, the succession of steps of adding material layer by layer generating openwork layers of material, each having a closed outline, the respective closed outlines of the openwork layers of material touching mutually in pairs and forming a closed envelope of the filler body for the blade.

The present disclosure concerns a method for manufacturing a composite panel including a cellular central core interposed between two skins. The manufacturing method includes the steps of manufacture of an element with a cellular structure comprising a cellular core structure interposed between two layers of structural plies intended to form the skins, positioning of the element with a cellular structure within a mold, formation of drains on either side of the cellular core structure, infusion of the element with a cellular structure so as to impregnate it with a resin, carrying out a draining of the resin through the drains in the element with a cellular structure during the infusion step, the drains having a geometry configured to provide draining, and polymerization of the impregnated element with a cellular structure to form the composite panel.

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 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.