A method and apparatus for resistive heating usable in composite-based additive manufacturing is disclosed. The method includes providing a prepared stack of substrate sheets, placing the stack between electrode assemblies of a compression device, applying a current to thereby heat the stack to a final temperature to liquefy applied powder, compressing the stack to a final height, cooling the stack, and removing the cooled, compressed stack from the compression device. The apparatus comprises at least two plates, a power supply for providing current, a first electrode assembly and a second electrode assembly.

Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an extrusion nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to extruding the filament from the extrusion nozzle.

The present invention provides a method for post-curing a profile (14) of fibre-reinforced plastic material comprising the steps of: • a supplying the profile, wherein the profile (14) is wound round a winding body (13) and wherein, as a result of the winding in the profile, stresses are present in the profile and said profile comprises a number of fibres extending along one another, which are embedded in a partially cured thermosetting matrix material, • b by means of a heat treatment device, carrying out a heat treatment on the profile (14) while the profile is wound round the winding body (13), and during said heat treatment the matrix material is post-cured, wherein the glass-transition temperature of the matrix material is increased as a result of the heat treatment and wherein the temperature to which the profile is exposed during the heat treatment remains below the glass-transition temperature during the heat treatment, wherein the stresses remain constant and as a result the shape is retained both in cross-section as well as radius of curvature of the profile, at least in the stress-free state, despite the heat treatment and despite winding the profile (14) round the winding body (13) prior to the heat treatment. The present invention also provides a profile manufactured by the method, and use of a profile manufactured by the method.

Systems and methods are provided for applying lengthwise curvature to composite parts. One embodiment is a method that includes fabricating a preform for a curved pultruded gap filler by continuously: heating fiber reinforced material to a sticking point temperature for a constituent material within the fiber reinforced material, and feeding the fiber reinforced material through a die that exhibits a curvature through which the fiber reinforced material travels while the fiber reinforced material is heated to the sticking point temperature, the die forming the fiber reinforced material into a preform for a gap filler. Fabricating the curved pultruded preform further includes varying path lengths of fibers within the preform as the preform passes through the die, and pulling the preform out of the die.

Methods for forming composite articles include providing a non-crimp fabric (NCF) comprising a plurality of fiber plies maintained in a layup by stitching, wherein the stitching exhibits a lower structural tolerance to heat and/or UV light relative to the fiber plies, selectively degrading the stitching in one or more areas using heat or UV light, draping the NCF on a contoured article, applying a polymer matrix material to the draped NCF, and curing the polymer matrix material to form a contoured composite article. The stitching can be degraded in regions of the NCF which, when draped on the contoured article, correspond to topological features of the contoured article. Degrading the stitching can comprise breaking the stitching. The fiber plies can comprise carbon fibers, glass fibers, and/or basalt fibers. The contoured article can be tooling and/or an automotive component. The NCF can be a bi-axial NCF.

Radius fillers for composite structures, composite structures that include the radius fillers, and systems and methods of forming the radius fillers. The systems and methods may be configured to create a pre-form that may be utilized to form a radius filler and/or to create a radius filler from the pre-form. The systems may include an apparatus configured to form the pre-form for the radius filler. This apparatus includes a composite tape source, a pre-forming structure, and a drive mechanism. The systems also may include an apparatus configured to form the radius filler. This apparatus includes a pre-form supply, a first radius filler die, a second radius filler die, and a die selection structure.

A method for manufacturing a semifinished product or part is disclosed in which a metal support embodied as a metal sheet or blank is covered with at least one prepreg containing a thermally cross-linkable thermosetting matrix with endless fibers, the thermosetting matrix of the prepreg is pre-cross-linked by means of heating, and the metal support covered with the pre-cross-linked prepreg is formed into a semifinished product or part by means of deep drawing or stretch deep drawing. In order to enable plastic deformation in fiber-reinforced regions of the metal support, it is proposed that during the pre-cross-linking of the thermosetting matrix of the prepreg, its matrix is transferred into a viscosity state that is higher than its minimum viscosity and prior to reaching its gel point, the prepreg is formed together with the metal support.

Equipment for forming a tubular rod of fibrous material comprises: a gathering station constructed to receive a continuous supply of fibres and to gather the fibres into a bundle as the fibres advance through the equipment; a divider arranged in the path of the fibres through the equipment and constructed to from a cleft along the length of the bundle as it advances through the equipment; a mandrel positioned in the path of the bundle of fibres in alignment with the divider and constructed to form the cleft into a passage through the bundle of fibres as the bundle of fibres advances over the mandrel; and a die constructed and arranged to cooperate with the mandrel to form the fibres in a tubular configuration around the mandrel.

A pre-preg product, such as a tape or sheet suitable for forming a composite having reinforcement fibers and a liquid crystal thermoset (LCT) precursor is provided. Further aspects of the invention are directed to a method for preparation of the pre-preg product and to composite products based on the pre-preg product.

A method of producing a fiber reinforced composite material satisfies condition 1: a thermosetting resin base material (B) includes a thermosetting resin (a) and a nonwoven fabric-shaped base material (a thermosetting resin base material satisfying the condition 1 is referred to as a thermosetting resin base material (B-1)); and condition 2: the thermosetting resin base material (B) is a base material including the thermosetting resin (a), and a porous sheet-shaped base material (b) or a film-shaped base material (c), the thermosetting resin (a) has a viscosity of 1,000 Pa.Math.s or more at 40° C., and the thermosetting resin (a) has a minimum viscosity of 10 Pa.Math.s or less during heating from 30° C. at a temperature rise rate of 1.5° C./min (a thermosetting resin base material satisfying the condition 2 is referred to as a thermosetting resin base material (B-2)).