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Fiber-Metal Laminates (FMLs) are composite materials that consist of conventional fiber reinforced plastics with the addition of a metal component, typically a foil or mesh layer(s). The metal component offers the advantage of incorporating metal-like properties to the composite construction. While a range of potential advantages and applications have been discussed for FMLs, the primary application to date has been for aircraft structures, with one potential advantage being the lightning strike protection (LSP) offered by the improved electrical conductivity. As aircraft construction has moved to composite structures, there has been an increasing need for such conductive composites. Similarly, with increasing use of composites for other large structures, e.g. wind turbines, there are an increasing number of potential applications for lightning strike protection materials. Other advantages of FML are improved impact and fire resistance. This innovation provides a method for making FML materials that incorporate nanotube reinforcement. The method involves the use of RF plasma spray to directly form and deposit nanotube materials onto fibers/fabrics, which can then be manufactured into composite structures by infiltrating the fiber with resin, and consolidating the structure via autoclave processing or via the use Vacuum Assisted Resin Transfer Molding (VARTM) composite manufacturing methods. Nanotubes incorporated into the structure in this manner can be of several types, for example boron nitride or carbon nanotubes. The objective of this innovation is to incorporate the nanotube materials in the FML in order to improve the mechanical properties.

The plasma system consists of a glass tube with a diameter of 0.5 mm or larger, if desired. The electrodes are separated by 10 mm. Helium, argon or cold dry air can be used as a plasma gas source. An applied high voltage between the electrodes causes the gas to breakdown within the central core of the glass capillary generating atmospheric plasma. Nanostructures colloids/organic/inorganic precursors are placed in a glass container with an inlet and outlet for carrier gas and are seated on an ultrasonic nebuliser. The aerosol is then carried into the plasma stream by the carrier gas and is deposited. The atmospheric plasma deposition system can be modified for depositing multiple materials, either simultaneously or sequentially, and for high-throughput processing by having multiple jets. Each capillary can either be connected to the container containing a single precursor material or to different containers containing different precursor materials to facilitate multiple depositions. The multi-jet plasma system can be automated and controlled individually to precisely control surface characteristics. This technique is independent of the chosen substrate, and has proven to work for many substrates, including paper, plastic, semiconductors and metals.

NASA’s Carbon Capture Filter was designed to trap solid carbon dust through a variety of mechanisms. These include inertial separation, flow recirculation, flow tortuosity, media filtration, and quenching of hot particles or of precursor particles from pyrolysis. The filter uses a custom-designed housing to produce a strong and large recirculating pattern to remove dust through inertial forces and confine it into a large collection cup, which is enshrouded in a cold trap (using a thermoelectric cooler) to thermally induce precipitation of the solid carbon. The flow then passes through a single stage baffle and tube filters before exiting through the outlet at the top of the housing. During operations, gaseous carbon-containing streams enter the filter via an inlet tube at the top of the housing. The inlet tube extends down towards the bottom of the collection cup, where the high-speed stream meets a sudden perpendicular bottom wall, inducing a stagnation flow. Large particles inertially separate from the flow and impinge onto the bottom wall. The partial enclosure of the collection cup (aside from a small slit connecting it to the upper chamber) causes a recirculation bubble to form, increasing the residence time of the stream. The vortical motion of the recirculation bubble causes the large particles to spin outwards towards the walls of the collection cup. The collection cup is cooled to quench the carbon particles, causing them to precipitate out and collect on the walls of the cup. The extended residence time caused by the recirculating flow further quenches the stream. Only small particles that are entrained sufficiently by the flow make it through the slit between the collection cup and upper chamber. On the top wall of the upper chamber, an array of tubular filters collects the remaining particles before the gaseous stream exits the system. NASA’s Carbon Capture Filter has been prototyped and undergone initial testing with simulant dust, yielding promising results. The invention is available for licensing to industry.

NASA's technique simplifies the seat installation process by requiring less installation equipment, eliminating the need for unnecessary apparatus such as fasteners and retainers. Multiple seals can be installed simultaneously, saving both time and money. NASA has tested the long-term performance of a solenoid actuated valve with a seat that was fitted using the new installation technique. The valve was fabricated and tested to determine high-cycle and internal leakage performance for an inductive pulsed plasma thruster (IPPT) application for in-space propulsion. The valve demonstrated the capability to throttle the gas flow rate while maintaining low leakage rates of less than 10^-3 standard cubic centimeters per second (sccss) of helium (He) at the beginning of the valves lifetime. The IPPT solenoid actuated valve test successfully reached 1 million cycles with desirable leakage performance, which is beyond traditional solenoid valve applications requirements. Future design iterations can further enhance the valve's life span and performance. The seat seal installation method is most applicable to small valve instruments that have a small orifice of 0.5 inches or less.