Abstract: A process for establishing bonded joints in the formation of multi-component adhered structures in which chemical bonding is established between adhesive and primer layers to provide for increased interlaminar strength. Curable resin primer layers are established on surfaces which are to be joined together in forming the multi-component structure. The primer resin is heated at a temperature and for a time period sufficient to expel substantial volatile matter from the resin, but insufficient to cross-link the resin to a completely cured state, thus leaving active bonding sites in the resinous primer layers. Bonding of the two components is provided by means of an intermediate adhesive layer between the mating surfaces. The adhesive layer is formed of a curable resin having bonding sites available for reaction with bonding sites in the primer resin.

Abstract: In a method of installing a septum (18) at a desired depth within a section of honeycomb core (12) for use in a sound attenuation panels, the septum is sandwiched between two layers (20, 24) of support material having a melting temperature intermediate between the fusing and curing temperatures of the septum material. The honeycomb core (12) is pressed into supporting materials and septum to segment and position the septum (18) therein, after which the resultant assembly is heated sufficiently to allow the septum to fuse and adhere to the honeycomb core. The resultant assembly is then heated sufficiently to melt the support material and allow it to be drained away, leaving the segmented septum (18) in place within the honeycomb core.

Abstract: A septum (18) is installed at a desired depth within a section of honeycomb core (12) for use in a sound attenuation panels, the septum is sandwiched between two layers (20, 24) of support material having a melting temperature intermediate between the fusing and curing temperatures of the septum material. The honeycomb core (12) is pressed into supporting materials and septum to segment and position the septum (18) therein, after which the resultant assembly is heated sufficiently to allow the septum to fuse and adhere to the honeycomb core. The resultant assembly is then heated sufficiently to melt the support material and allow it to be drained away, leaving the segmented septum (18) in place within the honeycomb core.