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Viewing 1 to 30 of 1607
2009-07-12
Technical Paper
2009-01-2519
Leonid Vasiliev, Marco Marengo, Claudio Ferrandi, Stefano Zinna, Viktor Maziuk
An advanced method for LHP evaporator wick manufacturing is suggested. A small-scale loop heat pipe (LHP) with an innovative nickel wick has been fabricated and tested to examine its thermal performances. The LHP container and the tubing of the system are made of stainless steel and two liquids, namely hexane and acetone, have been used as LHP working fluids. The ‘low-cost’ characteristic is given by the reduction of operations which are needed for the LHP wick fabrication. In this study LHP wick was sintered directly inside of the stainless steel tube. Thus the fabrication costs of the LHP wick are less compared with the standard ones for two manufacturing processes: i) compressing the nickel powders and ii) inserting of the wick into the stainless steel tube after the sintering process. Since especially the second process is very delicate and associated to production failures, the present LHP is several times cheaper than the standard LHP.
2008-09-16
Technical Paper
2008-01-2312
C. Jerry Brown, Mark W. Smith, Don Youngblood, Liang Zeng, Luke Haylock, Bob Gurrola, James P. Moran
Cadmium electroplating is coming under increasing pressure due to both environmental and worker safety issues. Since 2005, Alcoa Fastening Systems (AFS) and Lockheed Martin have been conducting a collaborative research program to identify the most appropriate fastener coating materials for a Cadmium (Cd) plating replacement. Four candidate coatings were selected for the initial Phase I evaluation: electroless nickel (EN), electroless nickel composite (EN-PTFE), electrodeposited surface mineralization based zinc-nickel (Zn-Ni), and electroplated aluminum (Al). The Phase I testing results indicated that the Zn-Ni and Al coatings were the best of the four candidates for Cd replacement. However, it is hard to conduct direct comparisons with different coating thicknesses, surface treatments, and lubrication among various Cd alternatives. Thus, further evaluation with more careful control of these parameters would be necessary.
2008-09-16
Technical Paper
2008-01-2323
Robbie Adams
Honeywell has developed a new approach to Solid Free-form Fabrication called Ion Fusion Formation (IFF), a Direct Metal Deposition (DMD) process. This is a near-net-shape hardware manufacturing process that uses a very hot ionized gas to deposit metal in small discreet amounts and ultimately build a complete part. Components can be used as-deposited or post-deposition processed to gain some improvement in properties and then final machined. The process has low initial capital, maintenance and operating cost and is user friendly. Other forms of SFF use expensive lasers or electron beam for their heat source. IFF uses inexpensive electrical energy to generate power for fusion.
2008-06-29
Technical Paper
2008-01-2201
Marc D. Porter, Lorraine M. Siperko, John Nordling, April A. Hazen-Bosveld, Chien-Ju Shih, Robert J. Lipert, James S. Fritz
At present, spacecraft water quality is assessed when samples collected on the International Space Station (ISS) are returned to Earth. Several months, however, may pass between sample collection and analysis, potentially compromising sample integrity by risking degradation. For example, iodine and silver, which are the respective biocides used in the U.S. and Russian spacecraft potable water systems, must be held at levels that prevent bacterial growth, while avoiding adverse effects on crew health. A comparable need exists for the detection of many heavy metals, toxic organic compounds, and microorganisms. Lead, cadmium, and nickel have been found, for instance, in the ISS potable water system at amounts that surpass existent requirements. There have been similar occurrences with hazardous organic compounds like formaldehyde and ethylene glycol. Microorganism counts above acceptable limits have also been reported in a few instances.
2007-07-09
Technical Paper
2007-01-3193
Roger R. Riehl
This paper presents an experimental investigation regarding the use of solid nanoparticles added to water as a working fluid, to form a so-called nanofluid. Tests were made with a miniature loop heat pipe (mLHP) and an open loop pulsating heat pipe (OLPHP). Results show that the addition of 3.5% (by mass) of nickel nanoparticles in water presented improvement on the mLHP thermal performance at heat loads around 10 W when compared with the operation with pure water. However, when operating at higher heat loads, the mLHP presented worse performance. When operating the mLHP and nanofluid with a concentration of 5% (by mass) of nickel nanoparticles, the device did not show reliable operation. The OLPHP was tested with water and copper nanoparticles at a concentration of 5% (by mass).
1992-08-03
Technical Paper
929093
D. Paugam, J. Verniolle, T. Jamin
: SAFT in cooperation with ESA (European Space Agency) and CNES (French Space Agency) has developed a 3.5 inches diameter NiH2 cell ranging from 36 to 100 Ah. This development program led to the qualification of the product performed according to ESA specifications on a batch of 15 cells of 90 Ah featuring an energy density of 58.2 Wh/Kg. The qualification program comprised a pre-vibration sequence with capacity measurement in standard conditions, leak rate measurement at maximum operating pressure, self-discharge and internal resistance determination, a sinusoidal and random vibration sequence followed by a post-vibration sequence to assess the stability of the performances after mechanical solicitations. The qualification sequence also comprises a capacity determination at -20, -5 and 25-C and a characterization of the cells behaviour under realistic GEO conditions.
1992-08-03
Technical Paper
929092
Carole A. Hill, James M. Matsumoto, Talmadge M. Poston, Alonzo Prater, Harry Brown, Steve Hall, Shaun House
Abstract There are currently 132 nickel hydrogen (NiH2) cells on test in a low earth orbit (LEO) regime at the Naval Surface Warfare Center, Crane Division. There are also 10 NiH2 cells in a special pulse test at the Aerospace Corporation. The testing, which is sponsored by the Air Force Phillips Laboratory, began in 1987. The majority of the cells have over four years of real time LEO cycles. The purpose of this paper is to provide a description of the NiH2 low earth orbit life test plan and to present the current status of cells in the test.
1992-08-03
Technical Paper
929111
S. A. Verzwyvelt, J. Berryman
Hydrogen gas pressure has been utilized to determine state of charge, efficiency on charge, establish voltage/current relationships and to derive an equivalent cell level DC resistance. In response to a fixed measurement cycle, the studied cell design is able to store more charge at lower temperatures. This is accomplished by more efficient charging to a higher cell voltage. However, as higher states of charge (pressure) are attained, the discharge profile depresses. This corresponds to an increased cell DC resistance. Furthermore, this cell level DC resistance increases with the depth of discharge and the rate of this increase is greater at lower temperatures.
1992-08-03
Technical Paper
929108
S. A. Verzwyvelt, J. Berryman
The determination of the hydrogen pressure equivalent to one amp hour of stored capacity has been conducted at various rates of charge and discharge and at different temperatures. Cell temperature control in this determination contrasts isothermal versus cold plate conditions. Selected regions of the hydrogen pressure plots are evaluated in terms of consistent cell pressure factors. Pressure factors determined on charge suggest a maximum coulombic efficiency of 96% to that obtained on discharge.
1992-08-03
Technical Paper
929321
Douglas Hafen
The electrical and thermal performance of a 40 Ah dual stack Nickel-Hydrogen (NiH2) cell has been characterized at 0°C and 10°C. The testing included standard capacity tests and electrical cycling using 100 minute cycling regimens, utilizing one of three modes: 1) Cycling containing 77A pulse loads applied for 6 msec followed by a 24A charge for 6 msec; 2) Constant current, constant depth-of-discharge (DOD) cycles; and 3) Constant DOD cycles with step changes in cell current at three points in the discharge. The testing was performed with the cell in a heat conduction calorimeter. The results of the test included amount of instantaneous heat generation during a typical LEO cycle, pressure vs. cutoff voltage data to establish a temperature-compensated voltage cutoff curve, and voltage characteristics suitable to generate a voltage prediction model. The inductive response to pulse loads is of interest and is discussed in the paper.
1990-04-01
Technical Paper
901055
David F. Pickett
Nickel alkaline batteries used in spacecraft electrical power subsystems are either nickel-cadium or nickel-hydrogen. The nickel-cadmium battery has been used since the beginning of the space program, while the nickel-hydrogen battery is a relative newcomer. Both couples are still used extensively, and recent advances in each have been documented. There are advantages and disadvantages in the use of either chemistry, but the nickel-hydrogen battery appears to be more attractive for longer life and higher specific energy for payloads greater than one kilowatt.
1994-04-01
Technical Paper
941227
J. N. Su, A. J. Steckl
High voltage Schottky diodes have been fabricated on 3C-SiC films grown on Si substrates. A Ni metallization process has been developed to fabricate both rectifying and ohmic contacts to SiC by controlling the post-annealing temperature. A high voltage (>150V) breakdown has been obtained at room temperature from the SiC Schottky diode. The Ni-SiC Schottky junction shows a thermal resistance for temperatures as high as 600°C. This technology has good potential for monolithic integration of SiC high power devices and Si integrated circuits.
1990-04-01
Technical Paper
900969
Arthur Wasserman
Particles e.g. Diamonds or Synthetic Diamonds (CBN) can be occluded in a controlled low stress Nickel Sulfamate deposit thru the use of a universal fixture design which provides for solution flow thru the particles pressed against the cathode. Methods of chemical manufacturing of Nickel Sulfamate and the controls in manufacturing and plating are discussed.
1990-04-01
Technical Paper
900964
George A. DiBari, Roger A. Covert
The electroplating anode completes the electrical circuit, distributes current to the parts being plated and influences metal distribution at the cathode. In addition, metal from a soluble anode may be converted into ions which enter solution and replenish those discharged at the cathode. There are important plating processes, however, that operate with insoluble anodes where the metal ion concentration in solution is controlled by the addition of soluble metal salts. Auxiliary and bi-polar anodes are used in conjunction with the primary anodes to improve coating thickness uniformity at the cathode. The influence of composition on anode behavior is illustrated by a review of the development of nickel anode materials. A subject of growing importance because of the associated disposal problems is the metal build-up that occurs when anode efficiency exceeds cathode efficiency. Complete automation of anode basket-loading operations may be possible.
1992-08-03
Technical Paper
929253
M. E. Daman, R. V. Whiteley, D. Debiccari
Eight 72 Ah nickel/hydrogen variant cell designs are currently undergoing LEO life testing at Space Systems/Loral. 2000 - 35% DOD LEO cycles have been completed to date. The variant designs incorporate various positive electrode parameters, stack designs, KOH concentration, and platinized/non-platinized wall wicks. BOL data indicates that observed variant performance differences are valid. Observations of effects of the selected parameters on cell performance will be statistically examined as part of continued cell evaluation. The life test is planned to continue for greater than five years.
1992-08-03
Technical Paper
929485
John J. Smithrick, Stephen W. Hall
Individual pressure vessel (IPV) nickel-hydrogen technology was advanced at NASA Lewis and under Lewis contracts with the intention of improving cycle life and performance. One advancement was to use 26 percent potassium hydroxide (KOH) electrolyte to improve cycle life. Another advancement was to modify the state-of-the-art cell design to eliminate identified failure modes. The modified design is referred to as the advanced design. A breakthrough in the Low-Earth-Orbit (LEO) cycle life of IPV nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent KOH electrolyte was about 40 000 LEO cycles compared to 3500 cycles for cells containing 31 percent KOH. The boiler plate test results are in the process of being validated using flight hardware and real time LEO test at the Naval Weapons Support Center (NWSC), Crane, Indiana under a NASA Lewis Contract. An advanced 125 Ah IPV nickel-hydrogen cell was designed.
1999-04-06
Technical Paper
1999-01-1366
Za Johnson, Tim Kulin, Andy Pai, Calvin Goroski
This manuscript addresses the characterization and evaluation of various nickel hydroxide half cells designed for use in aircraft batteries. Four different electrode configurations are examined for performance. Characterization testing includes evaluation for cycle life, utilization, capacity at temperature, and capacity at current.
1999-04-06
Technical Paper
1999-01-1385
David F. Pickett, Jeff W. Hayden, Dave Lucero
Since the late 1980s Super NiCd™ Batteries have been used by Hughes Space and Communications, Co. (HSC), NASA, TRW, Lockheed Martin Space and Missiles Group, and Johns Hopkins University Applied Physics Laboratory. In early flight programs with the technology, some capacity losses on long-term storage were experienced, but recently batteries with storage up to five years prior to launch are yielding within 2-3% of prestrorage capacity and are demonstrating managable performance in orbit.
1967-02-01
Technical Paper
670861
H. Shimizu, J. F. Dolowy, R. J. Taylor, B. A. Webb
Metal-matrix composites of aluminum, titanium, nickel and their alloys reinforced by continuous filaments of boron or silicon carbide are considered. The aluminum-boron system provides advantages at temperatures to 600 F for general application; the titanium-silicon carbide system shows promise for high-temperature applications;but the nickel-silicon carbide system presents problems in compatibility between the two materials at high temperatures. Selection of matrix alloys depends on filament loading, thermal history imposed by fabrication and usage requirements, the composite reinforcement geometry, and the nature of-stress distribution resulting from external loadings.
1982-02-01
Technical Paper
820612
Glen W. Dodd
Brush plating is a portable, selective plating process which is capable of on-site repairs and offers a technical and economic alternative to tank plating in many instances. Many applications of brush plating are simple and straightforward, but to take full advantage of its capabilities requires conscientious, well trained personnel and some creativity. In the aerospace industry, brush plating and anodizing technology have been used for both production and repair of hardware.
1983-02-01
Technical Paper
830693
Glenn O. Mallory, Dan Altura
The internal stress of electroless nickel (EN) deposits is shown to be the sum of two components, intrinsic and thermal. A method of measuring the stress components is discussed. The stress is shown to be dependent on the chemistry of the plating bath as well as the phosphorus content of the EN deposit. The corrosion behavior of EN deposits is shown to be dependent on stress and the near-surface phosphorus content. The effect of EN deposits on fatigue strength of steel is also discussed.
1985-04-01
Technical Paper
850905
Don L. Sheldon
This paper describes the fabrication of Electroformed Nickel tools for use in manufacturing composite parts. It further describes procedures and techniques used in developing this type of tools. To illustrate these steps, slides of a wing tool for the Mc Donnell - Douglas Harrier will be shown.
1987-02-01
Technical Paper
870752
Gary W. Smith
Recent advances in Selective “Brush Plating” technology combined with selectively plated Nickel Sulfamate coatings (Known in the industry as AeroNikl), permit the precise plating of close-tolerance small diameter holes, on a repetitive basis. The ability to “plate-to-size” small diameter holes should be of great interest to anyone involved with the manufacture or overhaul of aircraft quality parts or assemblies. Many close-tolerance parts are being “scrapped” during manufacture for discrepancies of 0.001 inch on the diameter, or less. The latest fixturing and plating techniques utilized by SIFCO Selective Plating technicians can correct such discrepancies in minutes, with high quality nickel sulfamate coatings. The time consuming and costly method of masking, tank plating, and remachining is avoided in most applications.
HISTORICAL
1942-03-01
Standard
AMS5025
CURRENT
2013-09-18
Standard
AMS4426B
This specification covers a magnesium alloy in the form of sand castings.
CURRENT
2012-12-04
Standard
AMS4470A
This specification covers an aluminum alloy in the form of plate.
CURRENT
2011-07-08
Standard
AMS4600
This specification covers an aluminum alloy in the form of sheet and plate.
2016-09-14
WIP Standard
AMS4600A
This specification covers an aluminum alloy in the form of sheet and plate.
HISTORICAL
1988-01-01
Standard
AMS4732B
This specification covers one type of copper-nickel alloy in the form of wire and ribbon.
HISTORICAL
1980-04-15
Standard
AMS4732A
This specification covers one type of copper-nickel alloy in the form of wire and ribbon.
Viewing 1 to 30 of 1607

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