Abstract: A method of making a joint for a structure comprises forming a thermoplastic filler, applying an uncured first thermoset layer into direct contact with the thermoplastic filler, applying an uncured second thermoset layer into direct contact with the thermoplastic filler, and applying an uncured third thermoset layer into direct contact with the thermoplastic filler. The method additionally comprises curing the uncured first thermoset layer, the uncured second thermoset layer, and the uncured third thermoset layer at a temperature below a melting temperature of the thermoplastic material to form a cured first thermoset layer, a cured second thermoset layer, and a cured third thermoset layer and bonding together the cured first thermoset layer, the cured second thermoset layer, the cured third thermoset layer, and the thermoplastic filler.

Abstract: There is provided a conductive radius filler system and method. The system has a composite assembly with one or more composite structures having one or more radius filler regions. The system further has one or more conductive radius fillers filling the one or more radius filler regions. Each of the conductive radius fillers has a conductive element of electrically conductive material. The system further has one or more conductive radius filler connections connecting the conductive radius fillers to one of, a fastener system, a fuel tank system, and a current generating system, to form one or more current handling systems of the system. The one or more current handling systems provide one of, edge glow mitigation of edge glow as a secondary effect of lightning strikes, electrostatic discharge mitigation of electrostatic discharge caused by refueling electrification and fuel slosh, and current return handling to provide a minimized dedicated conductive system.

Abstract: An apparatus includes a first thermoset layer that includes a first fibrous material embedded in a first thermoset matrix. The apparatus also includes a second thermoset layer that includes a second fibrous material embedded in a second thermoset matrix. The second thermoset layer is coupled to the first thermoset layer to form a joint. Further, a gap is defined between the first thermoset layer and the second thermoset layer. The apparatus also includes a thermoplastic filler that is made from a thermoplastic material. The thermoplastic filler is positioned within the gap.

Abstract: A composite radius filler include a base portion and a tip portion. The base portion is formed of composite plies varying in overall width along an overall lengthwise direction and defining a variable cross-sectional shape of the base portion along the lengthwise direction. The base portion includes at least one transition zone having a transition start and a transition end along the lengthwise direction. The composite plies of the base portion are arranged in one or more stacks each stack having a predetermined fiber orientation angle sequence and a stack width that changes within the transition zone. The tip portion includes a plurality of composite plies formed into a generally triangular cross-sectional shape and stacked on top of the base portion.

Abstract: An apparatus includes a first thermoset layer that includes a first fibrous material embedded in a first thermoset matrix. The apparatus also includes a second thermoset layer that includes a second fibrous material embedded in a second thermoset matrix. The second thermoset layer is coupled to the first thermoset layer to form a joint. Further, a gap is defined between the first thermoset layer and the second thermoset layer. The apparatus also includes a thermoplastic filler that is made from a thermoplastic material. The thermoplastic filler is positioned within the gap.

Abstract: A composite radius filler include a base portion and a tip portion. The base portion is formed of composite plies varying in overall width along an overall lengthwise direction and defining a variable cross-sectional shape of the base portion along the lengthwise direction. The base portion includes at least one transition zone having a transition start and a transition end along the lengthwise direction. The composite plies of the base portion are arranged in one or more stacks each stack having a predetermined fiber orientation angle sequence and a stack width that changes within the transition zone. The tip portion includes a plurality of composite plies formed into a generally triangular cross-sectional shape and stacked on top of the base portion.

Abstract: Apparatuses and methods of the present disclosure relate to efficient sealing of vacuum bag seams for vacuum bag processing of composite parts. Vacuum bags may enclose a composite part and form a first sealed region around the composite part. The first sealed region may be sealed by vacuum bag seams to a base supporting the composite part and/or to other vacuum bags. The vacuum bag seams may be sealed with an edge sealing frame that forms a compression seal and that defines a second sealed region including the sealed seam. Vacuum applied to the second sealed region forms a vacuum moat adjacent to the seam and/or at least partially surrounding the first sealed region. Hence, minor leaks in the compressively sealed seam are mitigated by the vacuum moat and the vacuum integrity of the first sealed region is maintained despite some potential leaks in the sealed seam.

Abstract: There is provided a conductive radius filler system and method. The system has a composite assembly with one or more composite structures having one or more radius filler regions. The system further has one or more conductive radius fillers filling the one or more radius filler regions. Each of the conductive radius fillers has a conductive element of electrically conductive material. The system further has one or more over-arching systems connected to the one or more conductive radius fillers, via one or more conductive radius filler connections, forming one or more current handling systems of the system. The one or more current handling systems include one or more of an edge glow handling system configured to handle edge glow, a static dissipation handling system configured to handle static dissipation, and a current return handling system configured to handle current return.

Abstract: A variable-radius laminated composite radius filler may include a base portion, a keyway portion, and a tip portion. The base portion may be formed of a plurality of variable width composite plies defining a variable cross-sectional shape of the base portion. The keyway portion may be stacked on the base portion and may be formed of a plurality of substantially constant width composite plies defining a substantially constant cross-sectional shape of the keyway portion. The tip portion may be stacked on the keyway portion and may be formed of composite plies.

Abstract: A method of forming a radius filler may include providing an upper portion having substantially constant width composite plies, providing a base portion as a stack of variable width composite plies, and stacking the upper portion onto the base portion to form a radius filler stack.

Abstract: Apparatuses and methods of the present disclosure relate to efficient sealing of vacuum bag seams for vacuum bag processing of composite parts. Vacuum bags may enclose a composite part and form a first sealed region around the composite part. The first sealed region may be sealed by vacuum bag seams to a base supporting the composite part and/or to other vacuum bags. The vacuum bag seams may be sealed with an edge sealing frame that forms a compression seal and that defines a second sealed region including the sealed seam. Vacuum applied to the second sealed region forms a vacuum moat adjacent to the seam and/or at least partially surrounding the first sealed region. Hence, minor leaks in the compressively sealed seam are mitigated by the vacuum moat and the vacuum integrity of the first sealed region is maintained despite some potential leaks in the sealed seam.

Abstract: An apparatus includes a first thermoset layer that includes a first fibrous material embedded in a first thermoset matrix. The apparatus also includes a second thermoset layer that includes a second fibrous material embedded in a second thermoset matrix. The second thermoset layer is coupled to the first thermoset layer to form a joint. Further, a gap is defined between the first thermoset layer and the second thermoset layer. The apparatus also includes a thermoplastic filler that is made from a thermoplastic material. The thermoplastic filler is positioned within the gap.