Abstract: A locally reinforced honeycomb core panel having a honeycomb core, at least one coiled insert in at least one honeycomb cell and at least one face sheet. These components are formed from high temperature resistant metals. Elongated foil strips are coiled into cylindrical shapes having diameters slightly less than the width of individual cells in the honeycomb panel and heights no greater than the depth of the cells. These coiled inserts are placed in individual cells in selected portions of the honeycomb core to locally improve density, strength and thermal transfer characteristics of the panel. The coiled inserts have sufficient resiliency so that when they are inserted into cells and allowed to unwind, they press tightly against the cell inside wall even if the cell shape has been distorted in handling. The cells are held in place by the face sheet(s) bonded to the honeycomb core. If desired, the coils may be bonded to the cell walls by diffusion bonding or brazing.

Abstract: A perforated flat ribbon heating element embedded or sandwiched between the porous material and perforated sheet of honeycomb acoustic panel material used for sound suppression and deicing on ice buildup areas of an aircraft engine.

Abstract: A method and resulting product produced by attaching a prepared maskant of a desired perforation pattern to cured compound contoured or flat advanced composite materials, directing a narrow stream of highly abrasive grit material of a selected particle size range through a relatively large nozzle under selected high pressure toward the maskant perforations at a very small angle relative to the perforation walls until perforations are formed in the advanced composite material according to the stencil perforation pattern. The perforated sheet produced is particularly adapted for use in sound attenuation structures.

Abstract: The disclosed process forms metal parts from a mixture containing a powdered metal, a plasticizer, and at least two binders. Some of these binder materials are selectively extractable from the mixture without sintering. After the mixture is shaped into the form of the desired part and prior to sintering, the plasticizer and the extractable binders are removed. This produces a part having both sufficient green strength and a relatively low binder content. On sintering, remaining binders decompose; and the resulting part has a carbon content of less than 1.0%.