A hollow core sheet having a plurality of channels and at least one bendable reinforcement rod adapted in width and thickness to a given channel dimensions for insertion inside a channel wherein the method of insertion consists in the steps of having the at least one bendable reinforcement rod having either or both of the width or the thickness having an outer dimension (OD) set between 0.50 0.75 of the given dimension of the channel with a variation of 5%.

An article of manufacture includes a cellular structure having one or more layers that are dispensed in a viscous form. Each of the one or more layers have a plurality of walls that define an array of cells, the array of cells being arranged to create a non-uniform relative density and/or cell geometry across a width and/or a length of the cellular structure, the width and the length being oriented substantially orthogonally to a depth of the cellular structure.

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.

Retention features are provided for joining at least two structural components in a fixtureless assembly system. A first structure including a groove may be configured to contain at least one adhesive, and a second structure may include a tongue configured to contact the at least one adhesive to join the first and second structures. The first structure may also include at least one window that receives electromagnetic (EM) radiation from an EM radiation source into the groove. The at least one adhesive is configured to cure at a first rate upon exposure to one of time or heating, and the at least one adhesive is configured to cure at a second rate faster than the first rate upon exposure to the EM radiation.

A composite drill pipe including an inner pipe having a first diameter, an outer pipe having a second diameter greater than the first diameter, and a plurality of flow channels formed between the inner pipe and the outer pipe. The plurality of flow channels are formed by a plurality of walls extending radially between an outer diameter of the inner pipe and an inner diameter of the outer pipe. A method of forming a composite drill pipe includes pultruding a drill pipe comprising an inner pipe having a first diameter, an outer pipe having a second diameter greater than the first diameter, and a plurality of flow channels formed between the inner pipe and the outer pipe. The method also includes providing a multi-directional reinforcement over an outer diameter of the outer pipe.

A method of manufacturing a resin-laminated board by preparing a pair of first and second split molds each of which is provided with a cavity; positioning two sheet materials made of a thermoplastic resin between the first and second split molds with the cavities of the first and second split molds opposed to each other; forming a plurality of recesses by recessing a first sheet material toward a second sheet material with use of a plurality of protrusions provided to the first split mold; and welding bottoms of the recesses to the second sheet material by clamping the pair of first and second split molds to obtain a resin-laminated board with a hollow structure. A mold includes a plurality of piece members, disposed at the cavity of the first split mold; and includes the protrusions and male screws provided to base ends of the protrusions.

A hollow core sheet having a plurality of channels and at least one bendable reinforcement rod adapted in width and thickness to a given channel dimensions for insertion inside a channel wherein the method of insertion consists in the steps of having the at least one bendable reinforcement rod having either or both of the width or the thickness having an outer dimension (OD) set between 0.50 0.75 of the given dimension of the channel with a variation of 5%.

Retention features are provided for joining at least two structural components in a fixtureless assembly system. A first structure including a groove may be configured to contain at least one adhesive, and a second structure may include a tongue configured to contact the at least one adhesive to join the first and second structures. The first structure may also include at least one window that receives electromagnetic (EM) radiation from an EM radiation source into the groove. The at least one adhesive is configured to cure at a first rate upon exposure to one of time or heating, and the at least one adhesive is configured to cure at a second rate faster than the first rate upon exposure to the EM radiation.

A thermoplastic laminate plank is described wherein the thermoplastic laminate plank includes a core, a print layer, and optionally an overlay. The core includes at least one thermoplastic material and has a top surface and bottom surface wherein a print layer is affixed to the top surface of the core and an overlay layer is affixed to the top surface of the print layer. An underlay layer can be located and affixed between the bottom surface of the print layer and the top surface of the core. In addition, a method of making the thermoplastic laminate plank is further described which involves extruding at least one thermoplastic material into the shape of the core and affixing a laminate on the core, wherein the laminate comprises an overlay affixed to the top surface of the print layer and optionally an underlay layer affixed to the bottom surface of the print layer.

An extrusion apparatus including a die and a mask are provided such that no slots feed directly into the longitudinal skin forming gap between the mask and the die. In a method of forming a die adapted to improve skin uniformity of extruded cellular ceramic substrates a slotted block of die material is provided including central slots adapted to form a cellular matrix of the substrate and peripheral slots located outwardly of the central slots designed to be covered by a skin former mask and adapted to extrude peripheral batch material. An arcuate skin former is cut corresponding to a target shrinkage so as to intersect the slotted block such that skin flow from tangent slots at 90 degree positions of the die is limited to the peripheral batch material.