Abstract: Rare earth metal switched magnetic devices that comprise one or more magnets, a rare earth metal element positioned in the magnetic field produced by the magnet(s) and a system for controlling the temperature of the rare earth metal element are disclosed. The rare earth metal element is formed of a rare earth metal or rare earth metal alloy having magnetic properties that change from ferromagnetic to paramagnetic when heated above the Curie temperature of the chosen rare earth metal or rare earth metal alloy. Preferably the Curie temperature of the chosen rare earth metal or rare earth metal alloy is at or below the ambient temperature in which the rare earth metal switched magnetic device is to be used—approximately room temperature (70° F.) in the case of devices intended for use in a factory. Tailored Curie temperatures can be obtained by alloying rare earth metals together and/or with conventional switchable “soft” magnetic metals—iron, nickel, and cobalt.

Abstract: An induction brazing uses a multisheet, diaphagm retort having isolated pressure zones to control the net tooling pressure at a level that avoids core crush. The isolated chambers in the multisheet diaphragm allow us to apply controlled pressure to the braze joint, especially at the elevated brazing temperature where the honeycomb core is soft and malleable.

Abstract: To virtually eliminate core crush in honeycomb sandwich structure for fixed leading edge panels, I rearrange the order of the plies. I use a full surface, facing ply of woven fabric impregnated with resin adjacent the core. This ply passes over an erosion strip at the part margin while lower plies terminate at the erosion strip. The facing ply is in contact with substantially the entire surface of the core along the entire skin-core interface to prevent slipping of the skin relative to the core during curing. I orient the facing ply 0/90.

Abstract: Increasingly stringent environmental restrictions make it challenging to apply coatings (i.e., paint) by conventional processes like spray painting because of the volatile solvents and hazardous pigments. The environmental scrutiny is particularly focused upon conventional corrosion protection surface treatments, especially chromated primers and conversion coatings. We apply appliqu{acute over (e)}s to provide a vapor barrier over the substrate to provide corrosion protection. We can make curved appliqu{acute over (e)}s on a family of molds of different Gaussian curvature and thereby avoid making a “splash” mold of the surface of interest to create the appliqu{acute over (e)}s. Using curved appliqu{acute over (e)}s reduces ridges, creases, or gaps that sometimes otherwise occur with attempts to a cover a surface with complex curvature with flat (planar) appliqu{acute over (e)}s.

Abstract: A hybrid tool serves as a form on which constituent materials are applied for bonding or curing into a part in a desired configuration. It also serves as a holder for the bonded or cured materials in the originally applied position during subsequent machining. The hybrid tool is made by fabricating a face sheet of composite material having a facing surface configured to the reverse of a desired shape of one surface of a part to be made on the tool. The actual part will be laid up on the facing surface, cured while on the tool, and even trimmed before release. Base structure of the tool holds the facing surface of the face sheet in the desired shape, and includes ground-engaging pads that define an “A” datum plane. The tool aligns a reference plane of the face sheet parallel to the datum plane. A substantially continuous groove in the face sheet, used for trimming the part, opens in the facing surface.

Abstract: A wideband antenna element includes a conductive plate parallel to, and spaced from a ground plane. A tapered dielectric material is positioned between the plate and ground plane. A pair of driving points to the plate are positioned fixed distances on either side of a center interconnect point between the plate and ground plane, to effect staggered tuning of the antenna element.

Abstract: The present invention provides a new architecture for MMIC circuitry that allows reception of electronically selectable single polarity or simultaneous dual polarity/dual beam signals by placed-array modules. Additionally, an improved phase shifter design that is smaller said requiring fewer electronic components than prior art phase shifters is disclosed. In particular, the phase shifter requires only a single control line for each stage of the phase shifter.

Abstract: Compression diffusion bonding according to the present invention uses a CRES template to apply increased pressure in the areas designated for diffusion bonds (DB) to improved the bond quality and to reduce the processing time. The CRES template is patterned to correspond with the DB arrangement in the superplastically formed part. The forming press forces the template against the pack of SPF sheets to provide 300-1200 psi or more pressure along the bond lines to speed their formation.

Abstract: Semiconductor materials optimized for their electrical conductivity and thermal conductivity promise much higher thermoelectric cooling power. The materials can achieve the same cooling or power generation capacity in thermopiles with less electron current compared with present bulk materials. Because less electron current is required to accomplish the same task, total thermopile semiconductor material cross-sectional area normal to thermal and electron flow is greatly reduced and the element length-to-cross-sectional area aspect ratio is increased. The net result is a significant improvement in the figure of merit, ZT, and in the device Coefficient of Performance (COP).

Abstract: A superplastically formed part having tailored thickness in particular areas includes a formed blank having a preformed portion and a formed portion. The preformed portion is preformed as a bulge into a recess in a die lid, and then the bulge is reversed into a cavity in a die base as a prethinned area which delivers unthinned portions of the blank for final forming to regions of the die base cavity over which thinned portions of the blank would otherwise be formed and further thinned by final forming.

Abstract: An induction heating workcell having a fixed solenoid coil heats parts more uniformly by aligning ferrite blocks, generally along the centerline of the coil, to improve uniformity of the magnetic field, magnetic flux, and power density. The blocks are nonconducting but have a high magnetic permeability so that flux prefers to travel through the block over surrounding structure. Therefore, the blocks are flux shapers that produce the desired temperature control.

Abstract: A concentrating coverglass allows efficient power generation for providing higher specific powers by space power arrays with weight penalties being countered by combining the functions of a solar concentrator and protective coverglass into a single element. A preferred frustoconical lens achieves a concentration ratio of about 4.5 at a thickness of about 1.0 mm. Efficient space power arrays with relatively wide tracking angle tolerance of up to about .+-.5.degree. using these coverglasses permit heavier payloads in the satellite's operating systems over traditional satellite designs.

Abstract: Sliding plugs use o-ring seals against the internal walls of an isostatic bulge forming die to apply end load to tube stock blanks during isostatic bulge forming. The die is made from two or more mating segments that assemble together to define a central channel for holding the tube stock blank. The plugs move inwardly into the die when the blank elongates or expands into the die, because such expansion reduces the internal pressure within the blank. The plugs are drawn inwardly because of the pressure decline in the blank. The plugs compress the ends of the blank and force the ends inwardly closer together. Such motion effectively feeds more material to the die and permits greater elongation in the completed part with tighter corner radii. Motion limiting shoulders on the plugs assure that the feeding of material is even from both ends. Typical range of motion for a plug is about 0.5 inches.

Abstract: Capitalizing on the unique feature of our induction heating workcell that permits rapid and controlled heating and cooling of a workpiece within a wide temperature range permits combining several manufacturing operations into a single heating cycle to save time, energy, capital, touch labor, and factory space. For example, we can combine superplastic forming (SPF) with annealing; two operations that occur at temperatures that differ by about 150-200.degree. F. (85-105.degree. C.) or more, to produce quality parts. We mill parts flat to simplify their machining, form them to complex curvature, and anneal them.

Abstract: Thick plate is difficult to form because it cracks when localized strain exceeds the limits of the material. Forming thick titanium would significantly reduce manufacturing costs for finished parts by reducing machining time and by allowing standard stock blanks to be used where twelve inch thick or thicker blanks are needed today. Using finite element analysis, we model the plate forming to determine processing constraints that allow forming the thick, coarse grained alpha-beta titanium plate according to SPF principles with controlled strain rates. We form the part at an elevated temperature with a press ram. We complete the part by machining the formed plate, thereby greatly reducing machining time and material cost. Typically we bend a 20 cm thick plate to about 130.degree. with a 5-6 inch inner radius bend, or we form 2 inch thick plate with a complex curvature exceeding twelve inch depth over an area of 30.times.60 inches.

Abstract: Thrust reverser inner wall structure comprising a thermally conductive nonmetallic carbon pitch fiber honeycomb core sandwiched between a top and bottom layer. The core is adhered by a reticulated layer of adhesive to a perforated carbon fiber top layer, and adhered to a base layer of nonmetallic, nonperforated carbon fiber reinforced fabric.

Abstract: Method and apparatus for the detection of a target receiver unit such as an enemy radar or radio receiver is disclosed. The surveillance system of this invention includes a transmitter unit coupled to an antenna to establish an electromagnetic surveillance field that includes signal components at two predetermined surveillance frequencies. When a target receiver is located within the surveillance field, the target receiver produces a second electromagnetic field having signal components at the intermodulation products of the surveillance field signal components due to a nonlinear mixing process that occurs within the target receiver. Signal components at predetermined intermodulation frequencies are detected by a receiver circuit within the surveillance system that has a passband excluding signal components at the two predetermined surveillance frequencies.

Abstract: We make large (in excess of 2 cm in diameter), single crystal YBa.sub.2 Cu.sub.3 O.sub.7-x [123 YBCO] crystals, where x.ltoreq.0.6, in a seventeen step process or some variant thereof from finely ground and well mixed 123 YBCO and 211 YBCO powders with a small amount of Pt by controlling the rate of cooling from within a compact of the powders using a temperature gradient in the radial and axial planes (independently) of about 1-1.degree. C./inch diameter of compact to nucleate the crystal growth. We promote crystal growth as well using a samarium oxide seed crystal, preferably SmBa.sub.2 Cu.sub.3 O.sub.(7-y), where y.ltoreq.1.6. After nucleation we cool the compact slowly at a rate from about 0.1-1.degree. C./hr to promote the single crystal development.

Abstract: The processing time and energy efficiency of metal or composite bonding operations is improved by heating the lay-up preform of the structure in an induction heating press where energy goes primarily to heating the workpieces rather than to heating the tooling or being lost to the environment. The bonding process is especially beneficial for joining thermoplastic composites, but it also can be used with metals or thermosets. Preferential heating at the bondline is achieved by using shims to define the bondline and to define bead regions that have relief from contact with the susceptor envelope because of the thickness of the shims in the bondline regions.

Abstract: A surface treatment for titanium and aluminum alloys forms a sol-gel film covalently bonded on the metal surface to produce strong, durable adhesive bonds between the metal and an organic adhesive without using toxic chemicals and while significantly reducing or eliminating rinse water requirements of traditional anodizing or etching processes. An aqueous sol containing an alkoxyzirconium and a glyddoxysilane with an organic acid catalyst and zirconium stabilizer is applied to etched or grit blasted substrates by dipping, spraying, or drenching, to produce bonds in a single application comparable in strength and performance to standard anodize controls. Parameters affecting performance include the sol composition, the Si/Zr ratio, the ratio of sol ingredients, the concentration of the sol, the carrier solvent, solution age, catalysts, surface pretreatment, application method, curing process, and primer used.