Hydrogen segregation in Ti-6Al-4V weldments made with unalloyed titanium filler metal
Hydride segregation in Ti alloy weldments made with unalloyed Ti filler metal, determining effect on mechanical properties
Koehl, B. G.↗
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Results for “filler”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Filler valve Patent
Filler valve design for supplying liquid propellants at high pressure to space vehicles
Macglashan, W. F., Jr.↗
Development of Pyrrone structural forms for honeycomb filler
The development of techniques for the preparation of Pyrrone structural foams for use as honeycomb filler is described. The feasibility of preparing foams from polymers formed by the condensation of 3,3'-diaminobenzidine (DAB), or 3,3',4,4'-tetraaminobenzophenone (TABP), with 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA) was investigated. Initially, most of the effort was devoted to preparing Pyrrone prepolymers with improved and more reproducible foaming properties for making chemically blown foams. When it became apparent that very high curing shrinkages would not allow the use of unfilled Pyrrone prepolymers in a foam-in-place process, emphasis was shifted from chemically blown foams to syntactic foams. Syntactic foam formulations containing hollow carbon microspheres were developed. Syntactic foams made from selected formulations were found to have very low coefficients of thermal expansion. A technique was developed for the emplacement of Pyrrone syntactic foam formulations in honeycomb core structures.
Kimmel, B. G.↗
Heat-moderating filler for intumescent coatings
Endothermic fillers improve insulative efficiency without interfering with intumescent properties.
Sawko, P. M.↗
A concept for improved fire-safety through coated fillers
A possible method is examined for obtaining a high value of thermal conductivity before ignition and a low value after ignition in standard composite materials. The idea is to coat fiberglass, alumina trihydrate, and similar fillers with specially selected chemicals prior to using polymer resins. The amount of the coat constitutes typically less than 5% of the material's total weight. The experimental results obtained are consistent with the basic concept.
Ramohalli, K.↗
High Temperature Filler for Tile Gaps
Gaps between ceramic tiles filled with ceramic-coated fabric that withstands temperatures as high as 2,000 degrees F (1,300 degrees C). Reusable high-temperature gap filler is made of fabric coated with ceramic slurry and bonded in place with room-temperature-vulcanized adhesive. Procedure used in kilns and furnaces.
Holt, J. W.↗
Internal Filler-Wire Feed For Arc Welding
Tungsten electrode for gas/tungsten arc welding contains lengthwise channel for feeding filler wire to weld joint. Channel makes it unnecessary to feed wire through guides outside electrode, conserving valuable space near weld and protects wire from deformation by contact with other parts in vicinity of weld. Helpful in robotic or automatic welding.
Morgan, Gene E.↗
Salt Filler For Making Covered Channels
In simple fabrication technique, metal salts used to create such subsurface channels as those for coolant in metallic heat exchanger. Layer of metal deposited on structure by vacuum plasma spraying, sealing channels. Metal salt or salt mixture has melting temperature higher than those of waxes and aluminum and withstands high temperature of plasma spraying. After plasma spraying, salt filler dissolved quickly and easily and flushed away with water or other appropriate solvent, leaving behind covered channels.
Mckechnie, Timothy N.↗
Platable Filler And Sealant
Mixture of facsimile compound and silver powder forms positive seal in small hole in metal sheet. Filled hole plated over by standard electrodeposition. Compound does not deteriorate in high plating-bath temperatures, unlike wax and other fillers. Provides surface to which plated metals readily adhere.
Heerman, Todd R.↗
Sensor Monitors Force On Filler Wire During Welding
Sensor measures lateral contact force between filler wire and weldment. Output of sensor fed as input to motorized wire-position controller, which strives to maintain desired contact force. Sensor built into wire-feed assembly. Pivoting arm transmits lateral force on tip of wire to load cell. Setscrews prevent underload and overload on load cell.
Morris, Tim↗
XPS analysis of the effect of fillers on PTFE transfer film development in sliding contacts
The development of transfer films atop steel counterfaces in contact with unfilled and bronze-filled PTFE has been studied using X-ray photoelectron spectroscopy. The sliding apparatus was contained within the vacuum of the analytical system, so the effects of the native oxide, hydrocarbon, and adsorbed gaseous surface layers of the steel upon the PTFE transfer behavior could be studied in situ. For both the filled and the unfilled PTFE, cleaner surfaces promoted greater amounts of transfer. Metal fluorides, which formed at the transfer film/counterface interface, were found solely in cases where the native oxide had been removed to expose the metallic surface prior to sliding. These fluorides also were found at clean metal/PTFE interfaces formed in the absence of frictional contact. A fraction of these fluorides resulted from irradiation damage inherent in XPS analysis. PTFE transfer films were found to build up with repeated sliding passes, by a process in which strands of transfer filled in the remaining counterface area. Under these reported test conditions, the transfer process is not expected to continue atop previously deposited transfer films. The bronze-filled composite generated greater amounts of transfer than the unfilled PTFE. The results are discussed relative to the observed increase in wear resistance imparted to PTFE by a broad range of inorganic fillers.
Blanchet, T. A.↗
More About Brazing Or Welding NiAl Without Filler
Two reports present additional information about two processes for joining, brazing, or welding workpieces made of nickel aluminide alloys, without use of filler metal. Joining processes involve uniform heating in vacuum-controlled furnace. Eliminates internal thermal gradients in workpieces joined and greatly reduces tendency toward cracking.
Moore, Thomas J.↗
Filler/ Polycarbosilane Systems as CMC Matrix Precursors
Pyrolytic conversion of polymeric precursors to ceramics is accompanied by loss of volatiles and large volume changes. Infiltration of a low viscosity polymer into a fiber preform will fill small spaces within fiber tows by capillary forces, but create large matrix cracks within large, intertow areas. One approach to minimizing shrinkage and reducing the number of required infiltration cycles is to use particulate fillers. In this study, Starfire allylhydridopolycarbosilane (AHPCS) was blended with a silicon carbide powder, with and without dispersant, using shear mixing. The polymer and polymer/particle interactions were characterized using nuclear magnetic resonance, differential scanning calorimetry, thermogravimetric analysis and rheometry. Polymer/particulate slurries and suspensions were used to infiltrate a figidized preform of an eight ply five harness satin CG Nicalon fiber having a dual layer BN/SiC interface coating, and the resulting composites characterized by optical and scanning electron microscopy.
Hurwitz, Frances I.↗
Filler Wire Development for 2195 Aluminum-Lithium
The objective of the research was to determine the susceptibility of submitted welded 2195 plate in an AI (Alternate Immersion) environment. Forty-day AI exposure was completed on 8 welded 2195 stress corrosion samples. No stress corrosion cracking (SCC) was found on any of the samples tested. All 8 samples experienced exfoliation corrosion attack in the heat-affected zone (HAZ) adjacent to the weld. All samples were examined metallographically and showed varying degrees of intergranular corrosion (IG). The filler metal on all samples showed moderate to heavy pitting.
Bjorkman, Gerald W.↗
Implementation of a Thick-Film Composite Li-Ion Microcathode Using Carbon Nanotubes as the Conductive Filler
This paper describes the development of a thick-film microcathode for use in Li-ion microbatteries in order to provide increased power and energy per area. These cathodes take advantage of a composite porous electrode structure, utilizing carbon nanotubes (CNT) as the conductive filler. The use of carbon nanotubes was found to significantly reduce the measured resistance of the electrodes, increase active material accessibility, and improve electrode performance. In particular, the cycling and power performance of the thick-film cathodes was significantly improved, and the need for compression was eliminated. Cathode thickness and CNT content were optimized to maximize capacity and power performance. Power capability of >50 mW/sq cm (17 mA/sq cm) with discharge capacity of >0.17 mAh/sq cm was demonstrated. The feasibility of fabricating thick-film microcathodes capable of providing the power and capacity needed for use in autonomous microsensor systems was also demonstrated.
Lin, Qian↗
Characterization of Solid Polymers, Ceramic Gap Filler, and Closed-Cell Polymer Foam Using Low-Load Test Methods
Various solid polymers, polymer-based composites, and closed-cell polymer foam are being characterized to determine their mechanical properties, using low-load test methods. The residual mechanical properties of these materials after environmental exposure or extreme usage conditions determines their value in aerospace structural applications. In this experimental study, four separate polymers were evaluated to measure their individual mechanical responses after thermal aging and moisture exposure by dynamic mechanical analysis. A ceramic gap filler, used in the gaps between the tiles on the Space Shuttle, was also tested, using dynamic mechanical analysis to determine material property limits during flight. Closed-cell polymer foam, used for the Space Shuttle External Tank insulation, was tested under low load levels to evaluate how the foam's mechanical properties are affected by various loading and unloading scenarios.
Herring, Helen M.↗
Thermal Control Method for High-Current Wire Bundles by Injecting a Thermally Conductive Filler
A procedure was developed to inject thermal filler material (a paste-like substance) inside the power wire bundle coming from solar arrays. This substance fills in voids between wires, which enhances the heat path and reduces wire temperature. This leads to a reduced amount of heat generated. This technique is especially helpful for current and future generation high-power spacecraft (1 kW or more), because the heat generated by the power wires is significant enough to cause unacceptable overheating to critical components that are in close contact with the bundle.
Rodriguez-Ruiz, Juan↗
Gap Filler Induced Transition on the Mars Science Laboratory Heatshield
Detached Eddy Simulations have been performed to investigate the effects of high-fidelity turbulence modeling on roughness-induced transition to turbulence during Mars entry. Chemically reacting flow solutions will be obtained for a gap filler of Mars Science Laboratory at the peak heating condition.
Yoon, Seokkwan↗