Abstract: Composite fabrication system and associated methods. In one embodiment, a composite fabrication system comprises a molding tool that includes a forming surface at least partially disposed within a constrained space, and a foamable material that expands inside of the constrained space to form an expanded material that presses a layup of one or more composite layers against the molding tool. The composite fabrication system further comprises a curing device configured to cure the layup to form a composite part, and a cutting wire embedded in the constrained space that is heated and configured to cut the expanded material into pieces that are removable from the constrained space.

Abstract: A breather used for vacuum bag compaction of a composite laminate part is semi-permanently installed on a compaction tool. The breather is a channel member having an internal passageway that routes air and volatiles from the vacuum bag to a vacuum port in the tool.

Abstract: Methods of recovering and/or recycling expanded polymer tooling, the methods including collecting expanded polymer tooling, reducing the collected expanded polymer tooling into smaller particles, treating the reduced expanded polymer tooling in order to yield an at least partially purified recovered polymer composition, and then collecting the at least partially purified recovered polymer composition. The at least partially purified recovered polymer composition can then be used to form new expandable polymer tooling.

Abstract: Methods of manufacturing composite workpieces that include adding an expandable element to an internal volume of a constraining container proximate to a uncured composite workpiece supported on a rigid form, where the expandable element is configured to expand when a predetermined change is produced in an attribute of the expandable element; expanding the expandable element by producing the predetermined change in the attribute of the expandable element, so that an expansion of the expandable element applies pressure to the workpiece supported on the rigid form within the internal volume, and curing the composite workpiece while the resulting pressure is applied to the workpiece supported on the rigid form.

Abstract: Methods of recovering and/or recycling expanded polymer tooling, the methods including collecting expanded polymer tooling, reducing the collected expanded polymer tooling into smaller particles, treating the reduced expanded polymer tooling in order to yield an at least partially purified recovered polymer composition, and then collecting the at least partially purified recovered polymer composition. The at least partially purified recovered polymer composition can then be used to form new expandable polymer tooling.

Abstract: A method of curing a composite part, including placing an uncured composite part on a mandrel, placing a plurality of expandable pellets on the uncured composite part, expanding the plurality of expandable pellets, applying a positive pressure to the uncured composite part, and curing the uncured composite part.

Abstract: Methods of manufacturing composite workpieces that include adding an expandable element to an internal volume of a constraining container proximate to a uncured composite workpiece supported on a rigid form, where the expandable element is configured to expand when a predetermined change is produced in an attribute of the expandable element; expanding the expandable element by producing the predetermined change in the attribute of the expandable element, so that an expansion of the expandable element applies pressure to the workpiece supported on the rigid form within the internal volume, and curing the composite workpiece while the resulting pressure is applied to the workpiece supported on the rigid form.

Abstract: A forming apparatus includes a frame. The frame defines a vertical axis, a horizontal axis, and a longitudinal axis. A carriage is movably connected to the frame. A stomp foot is movably connected to the carriage such that it may move along the vertical axis. A first end effector is movably connected to the carriage and a second end effector movably connected to the carriage. The first end effector and second end effector are laterally opposed to each other along the longitudinal axis and the stomp foot is located between the first end effector and the second end effector.

Abstract: A system for curing a composite part, includes a mandrel configured to receive and support the uncured composite part; a plurality of expandable pellets disposed on the uncured composite part; and a mold configured to hold the mandrel, the uncured composite part, and the plurality of expandable pellets, wherein the plurality of expandable pellets are configured to expand and apply a positive pressure to the uncured composite part according to a change in condition or triggering event, and wherein each of the plurality of expandable pellets includes a blowing agent, a polymer matrix configured to hold the blowing agent, and a flexible skin configured to encapsulate the polymer matrix and the blowing agent, wherein the flexible skin is at least partially permeable with respect to the blowing agent or a gas released by the blowing agent.

Abstract: A method, apparatus, system, and computer program product for fabricating a composite part. Composite materials are laid up on a mandrel. A caul is placed over the composite materials laid up on the mandrel. An inner mold line of the caul is sized to an outer surface of the composite materials in a cured state. The composite materials laid up on the mandrel with the caul over the composite materials is cured to form the composite part. The composite materials expand to the inner mold line of the caul during curing of the composite materials to form the composite part.

Abstract: A composite structure including a multi-layer laminate having a plurality of regions each oriented out of plane relative to an adjacent region, and each extending in a longitudinal dimension of the multi-layer laminate, wherein the multi-layer laminate includes at least one ply layer having an oblique fiber orientation relative to the longitudinal dimension, and wherein the at least one ply layer includes a first section and a second section each having a side edge, the first and second sections aligned side-by-side such that a first interface defined between the respective side edges is oriented to extend in the longitudinal dimension.

Abstract: Methods of manufacturing composite workpieces that include positioning a heat-generating element proximate to an uncured composite workpiece, triggering the heat-generating element to produce an exothermic chemical reaction or exothermic physical reaction so that the temperature of the uncured composite workpiece is raised to a predetermined first temperature, and curing the composite workpiece while it is at a temperature that is at least the predetermined first temperature.

Abstract: A composite laminate stiffener is formed to contour with reduced ply wrinkling using constrained creep forming. The tooling apparatus is provided with flexible cauls which constrain the stiffener during the contour forming process. The creep forming is carried out at a slow enough rate so that friction or shear resistance between the resin and fibers of the plies remains low enough that slippage can occur and significant compression stresses are not generated rate, allowing relaxation of residual stresses in the stiffener.

Abstract: A flexible caul for applying pressure to a part comprises a caul member having a plurality of spaced apart gaps therein to provide the caul member with flexibility, and a flexible covering that limits flexing of the caul member.

Abstract: Methods of manufacturing composite workpieces that include adding an expandable element to an internal volume of a constraining container proximate to a uncured composite workpiece supported on a rigid form, where the expandable element is configured to expand when a predetermined change is produced in an attribute of the expandable element; expanding the expandable element by producing the predetermined change in the attribute of the expandable element, so that an expansion of the expandable element applies pressure to the workpiece supported on the rigid form within the internal volume, and curing the composite workpiece while the resulting pressure is applied to the workpiece supported on the rigid form.

Abstract: A structure comprising a plurality of walls defining a bladder cavity, the bladder cavity comprises an initial cross section size. A first plurality of wave features provided along at least one of the plurality of walls defining the bladder cavity. In one arrangement, the first plurality of wave features allow the structure to expand from the initial cross section size to a second cross section size after the structure becomes inflated during a composite charge cure, the second cross section size larger than the initial cross sectional size.

Abstract: A composite structure including a multi-layer laminate having a plurality of regions each oriented out of plane relative to an adjacent region, and each extending in a longitudinal dimension of the multi-layer laminate, wherein the multi-layer laminate includes at least one ply layer having an oblique fiber orientation relative to the longitudinal dimension, and wherein the at least one ply layer includes a first section and a second section each having a side edge, the first and second sections aligned side-by-side such that a first interface defined between the respective side edges is oriented to extend in the longitudinal dimension.

Abstract: Composite fabrication system and associated methods. In one embodiment, a composite fabrication system comprises a molding tool that includes a forming surface at least partially disposed within a constrained space, and a foamable material that expands inside of the constrained space to form an expanded material that presses a layup of one or more composite layers against the molding tool. The composite fabrication system further comprises a curing device configured to cure the layup to form a composite part, and a cutting wire embedded in the constrained space that is heated and configured to cut the expanded material into pieces that are removable from the constrained space.

Abstract: A forming apparatus includes a frame. The frame defines a vertical axis, a horizontal axis, and a longitudinal axis. A carriage is movably connected to the frame. A stomp foot is movably connected to the carriage such that it may move along the vertical axis. A first end effector is movably connected to the carriage and a second end effector movably connected to the carriage. The first end effector and second end effector are laterally opposed to each other along the longitudinal axis and the stomp foot is located between the first end effector and the second end effector.

Abstract: A system for curing a composite part, includes a mandrel configured to receive and support the uncured composite part; a plurality of expandable pellets disposed on the uncured composite part; and a mold configured to hold the mandrel, the uncured composite part, and the plurality of expandable pellets, wherein the plurality of expandable pellets are configured to expand and apply a positive pressure to the uncured composite part according to a change in condition or triggering event, and wherein each of the plurality of expandable pellets includes a blowing agent, a polymer matrix configured to hold the blowing agent, and a flexible skin configured to encapsulate the polymer matrix and the blowing agent, wherein the flexible skin is at least partially permeable with respect to the blowing agent or a gas released by the blowing agent.