Prepregs, cores and composite articles are described that comprise lighter weight materials and/or lower amounts of adhesive than commonly used. In some instances, one or more components of the articles may comprise a repellent material or repellent treatment to reduce the overall absorption rate of adhesive into the components of the article.

A method is provided for connecting hollow profiles (1-4) in a joint (10) to produce a load-bearing structure (5). The method includes placing ends of hollow profiles (1-4) in a mold and pressing the ends together with at least one semi-finished product to connect the ends of the hollow profiles to the semi-finished product.

A triaxial laid scrim includes a first, second and third set of continuous fibers. The fibers of each set are regularly spaced apart and are parallel to each other. The fibers of the first set are parallel to the warp direction or to the weft direction of the scrim. The fibers of the second set and the third set are oriented symmetrically to each other, respectively at an angle of 30°-80° with respect to the fibers of the first set. Distances between the fibers of the second set and the fibers of the third set are identical. The fibers of the second set cross the fibers of the third set at the intersection thereof with the fibers of the first set, thereby defining regular openings having an isosceles triangle shape. The fibers are coated and attached to each other by a coating that does not fill-up the triangle-shaped openings.

Fibre-reinforced composite materials, which can exhibit good fire-retardant properties in combination with good surface properties and aesthetic properties, as well as good mechanical properties, and in conjunction with good processability, with regard to cost and health and safety considerations.

A metal-carbon fiber reinforced plastic composite comprising a metal member of a ferrous material or ferrous alloy, a resin layer provided on at least one surface of the metal member and including a thermosetting resin, and carbon fiber reinforced plastic provided on a surface of the resin layer and including a carbon fiber material and a matrix resin having thermoplasticity, an indentation elastic modulus at 160 to 180° C. of the resin layer being higher than an indentation elastic modulus at 160 to 180° C. of the matrix resin.

A metal-carbon fiber reinforced plastic composite comprising a metal member of a ferrous material or ferrous alloy, a resin layer provided on at least one surface of the metal member and including a thermosetting resin, and carbon fiber reinforced plastic provided on a surface of the resin layer and including a carbon fiber material and a matrix resin having thermoplasticity, an indentation elastic modulus at 160 to 180° C. of the resin layer being higher than an indentation elastic modulus at 160 to 180° C. of the matrix resin.

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.

An additive manufacturing system is disclosed. The additive manufacturing system may include a moveable support, and a print head connected to the moveable support. The print head may be configured to discharge a continuous reinforcement that is wetted with a liquid matrix. The additive manufacturing system may also include an auto-threader configured to thread the continuous reinforcement through the print head, and a controller in communication with the moveable support, the print head, and the auto-threader. The controller may be configured to selectively activate the auto-threader at a start of a manufacturing process.

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.

Proposed is a hydraulic cylinder rod in which a rod eye is robustly coupled to a hybrid round rod for weight reduction. To this end, the hydraulic cylinder rod is configured with a hybrid round rod including a metal tube and a composite material round rod provided for weight reduction inside the metal tube, wherein a side of the metal tube is formed to be relatively longer than the length of the composite material round rod to thereby provide a space defined by a length difference therebetween; and a rod eye is coupled to the space.