A beaded composite panel is fabricated using composite plies. An opening is formed in each of plies, and each ply is laid up on a bead feature and drawn down over the bead feature in the area of the opening so as to widen the opening into a gap allowing the ply to conform to the contour of the bead feature. Patches are fabricated and placed on the plies overlying over the openings. The laid-up plies are compacted and cured.

Sulfur-containing polyurea compositions comprising a polyisocyanate and a polyamine are disclosed. The polyisocyanate comprises the reaction product of reactants comprising a diisocyanate having isocyanate groups with different reactivities toward thiol groups, and a thiol-terminated sulfur-containing polymer such as a thiol-terminated polythioether polymer and/or a thiol-terminated polyformal polymer. The polyamine can be an aromatic polyamine and/or an aromatic amine-terminated polythioether adduct. The sulfur-containing polyurea compositions are useful as aerospace sealants.

A method for repairing a honeycomb core sandwich structural body according to the present invention is a method in which a damaged portion that is formed in a honeycomb core sandwich structural body where a honeycomb structured core is held between a first outer skin and a second outer skin and that reaches the core through the first outer skin is repaired, the method including: a repair material mounting step of mounting a repair material on the damaged portion, the repair material including a patch that covers an opening of the damaged portion, and one or a plurality of braces that support the patch; a patch bonding step of bonding the patch to the first outer skin; and a brace bonding step of bonding the brace to the second outer skin or the core.

A method for fabricating a repair laminate for a composite part having an exposed surface includes applying a release film to the exposed surface and forming an uncured ply stack assembly on the release film. The uncured ply stack assembly is formed by forming and compacting a series of uncured ply stacks. The release film and ply stack assembly is then removed from the exposed surface. A bonding material is then applied to the exposed surface, and the uncured ply stack assembly is applied to the bonding material. The ply stack assembly and bonding material are then cured.

A method for repairing damage to a composite part includes creating an aperture through the composite part and preparing the surfaces surrounding the aperture on both sides of the part; inserting a plurality of resin impregnated fibers through the aperture and spreading the end portions of the plurality of fibers radially against the prepared surfaces on both sides of the part; and maintaining contact of the plurality of fibers with the prepared surfaces while the resin cures.

A sandwich structure configured to be secured with a mechanical fastener includes a core assembly, which includes a polymer component configured for supporting a mechanical fastener connector insert. The core assembly further includes an open cellular component formed from a plurality of self-propagating photopolymer waveguides positioned around the polymer component, wherein a first portion of the plurality of self-propagating photopolymer waveguides is secured to and extends from the polymer component. Further included is a first face sheet secured to a first side of the core assembly, wherein the first portion of the plurality of self-propagating photopolymer waveguides has a distal end spaced apart from the polymer component and secured to the second face sheet.

Diecuts are configured for permanent closing of holes and have a carrier comprising an assembly of at least two polymeric films. An upper film of the at least two polymeric films has a basis weight of at least 1.0 kg/m.sup.2 and a lower film of the at least two polymeric films consisting of at least two layers, wherein a first layer is in the form of a polymeric film and faces the upper film, and a second layer is in the form of a functional layer with a side of the lower film, facing away from the upper film, bears an applied adhesive composition.

The disclosure provides, in part, adhesive patches for repairing damaged surfaces of health care devices. In one of its aspects the disclosure provides a method of repairing the surface of health care device by applying an adhesive patch over a damaged portion of the surface, the patch comprising a film layer and an adhesive layer. In another one of its aspects, the disclosure provides an adhesive patch for repairing the surface of a health care device comprising a film layer and an adhesive layer.

The invention relates to a device for producing, repairing and/or replacing a component, particularly an aircraft component, by means of a powder that can be solidified by energy radiation of an energy radiation source, characterized in that the device comprises an application unit that is designed such that the powder can be applied onto an uneven surface by means of the application unit.

A sandwich structure configured to be secured with a mechanical fastener includes a core assembly, which includes a polymer component configured for supporting a mechanical fastener connector insert. The core assembly further includes an open cellular component formed from a plurality of self-propagating photopolymer waveguides positioned around the polymer component, wherein a first portion of the plurality of self-propagating photopolymer waveguides is secured to and extends from the polymer component. Further included is a first face sheet secured to a first side of the core assembly, wherein the first portion of the plurality of self-propagating photopolymer waveguides has a distal end spaced apart from the polymer component and secured to the second face sheet.