Abstract: Lightweight, structurally integral enclosures with walls stiffened and strengthened by integral and joined reinforcing ribs which may also serve as heat sinks. These ribs, which may be capped or uncapped and located on the inner or outer sides of the enclosure walls, are formed by chemical milling. Wall components are preferably joined by electron beam welding. Seals may be used between the walls and a closure to isolate the interior of the enclosure. In electronic applications, conductive seals and sealants are employed to provide uniform and continuous shielding from electromagnetic interference and radio frequency interference.

Abstract: A high strength panel-like structure having a high strength to weight ratio. The structure comprises two integrally formed panel sections, each panel section comprising an outer sheet portion and inwardly extending ribs that are formed integrally with the related sheet portions, and having inner bonding surfaces spaced from their respective sheet portions. The two panel sections are formed into a unitary structure by bonding the two sections at the bonding surfaces of the ribs. Thus, the bonding area of the panel structure is at the neutral axis of the structure. Desirably inner bonding surfaces of the ribs have a width dimension greater than a width dimension of the ribs.

Abstract: Methods of, and equipment for, protecting selected parts of a component against overheating while the component is being thermally treated.

Abstract: Integrally stiffened skin structures (72, 88, 96) which can advantageously be substituted for structures of the honeycomb, skin-and-stringer, and integrally machined types. Exemplary of a virtually endless list of components in which the integrally stiffened skin structures can be employed are jet engine components, aircraft and missile fuselages, jet engine pods, aircraft landing brake components, components with compound curvatures such as bulkheads and fairings, flat and curved panels, and conical and other shell-like components. Materials from which the structures can be fabricated include stainless steels, superalloys, titanium and aluminum alloys, other metals, and a variety of composites including those advanced ones with a high strength-to-weight ratio.

Abstract: Methods for fabricating metallic components in which expansion of a mandrel and changes that take place in the workpiece material during precipitation hardening--phase changes, volume contraction, and increased ductility--are utilized to size the component to a selected diameter and to stabilize the component at that diameter. Mandrels for such methods.

Abstract: Methods for shaping metallic workpieces which utilize a single faced die and the use of heat and pressure to conform the article to the shape of the die surface by creep forming.

Abstract: Chemical milling processes which employ a series of masking and metal removal steps. Apparatus for orbiting the workpiece in a prescribed manner about mutually perpendicular axes during the metal removal steps.

Abstract: Chemical milling processes which employ a series of masking and metal removal steps. Apparatus for orbiting the workpiece in a prescribed manner about mutually perpendicular axes during the metal removal steps.