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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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At least 73 records · Page 4

Elevated-temperature application of the IITRI compression test fixture for graphite/polyimide filamentary composites

Seventy-nine graphite/polyimide compression specimens were tested to investigate experimentally the IITRI test method for determining compressive properties of composite materials at room and elevated temperatures (589 K (600 F)). Minor modifications were made to the standard IITRI fixture and a high degree of precision was maintained in specimen fabrication and load alignment. Specimens included four symmetric laminate orientations. Various widths were tested to evaluate the effect of width on measured modulus and strength. In most cases three specimens of each width were tested at room and elevated temperature and a polynomial regression analysis was used to reduce the data. Scatter of replicate tests and back-to-back strain variations were low, and no specimens failed by instability. Variation of specimen width had a negligible effect on the measured ultimate strengths and initial moduli of the specimens. Measured compressive strength and stiffness values were sufficiently high for the material to be considered a usable structural material at temperatures as high as 589 K (600 F).

Raju, B. B.↗

L4-3 Developing DOE M441.1-1 Compliant Container Components: Filter Cup Experimental Fixture Test Data Verification

This document serves to provide technical documentation and justification for using the Filter Cup Experimental Fixture (FCEP) for filter efficiency and pressure drop testing in the Enhanced Filter Test System (EFTS). This document assumes that the reader has prior knowledge related to both of these systems, as well as the SAVY-4000® nuclear material container series filter technology.

42 ENGINEERING↗

Adhesive-Bonded Fixture for Flexure Testing

Fixture for flexural tests of glass-fiber-reinforced epoxy rods 1/4 in. (6.4 mm) in diameter easy to fabricate. Little machining done by relatively unskilled. Flexural-test fixture allows bending stress applied to specimen rod while holding rod securely. Dowel pins, blocks, and plate that make up fixture joined by adhesive.

Clemons, J. M.↗

Space Shuttle AFRSI OMS pod environment test using model 81-0 test fixture in the Ames Research Center 9x7-foot supersonic wind tunnel (OS-314A/B/C)

A test was conducted in the NASA/Ames Research Center 9x7-foot Supersonic Wind Tunnel to help resolve an anomaly that developed during the STS-6 orbiter flight wherein sections of the Advanced Flexible Reusable Surface Insulation (AFRSI) covering the OMS pods suffered some damage. A one-third scale two-dimensional shell structure model of an OMS pod cross-section was employed to support the test articles. These consisted of 15 AFRSI blanket panels form-fitted over the shell structures for exposure to simulated flight conditions. Of six baseline blankets, two were treated with special surface coatings. Two other panels were configured with AFRSI sections removed from the OV099 orbiter vehicle after the STS-6 flight. Seven additional specimens incorporated alternative designs and repairs. Following a series of surface pressure calibration runs, the specimens were exposed to simulated ascent and entry dynamic pressure profiles. Entry conditions included the use of a vortex generator to evaluate the effect of shed vortices on the AFRSI located in the area of concern.

Collette, J. G. R.↗

Accelerating Laboratory-Based, All-Solid-State Battery Research and Development: Industrially Relevant Small-Batch Dry-Processing, Small and Low-Cost Test Fixtures, and Short-Tolerant Separators

This work presents improvements to mixing (for dry-processed electrodes), separator robustness, and cell testing jigs for all-solid-state batteries (ASSBs). These developments combine synergistically to enable rapid research and development of ASSB catholytes. A mechanical "kneader" is designed and built which emulates the mixing and fibrillation of poly-tetrafluoroethylene binder that occurs in industrially relevant twin-screw extruders. A modest improvement in the mixing and dispersion catholyte materials is observed using micro-resolution X-ray computed tomography (X-ray CT). Catholytes are paired with an In-metal anode and separated by a novel, dual-layer, polyaramid-fiber-supported, sulfide-solid electrolyte (Li6 PS5 Cl) separator. This separator achieves high short tolerance which enabled a 95% success rate across 20 attempted cells and to date over 100 successful cells have been built. ASSBs were tested in a 2032 coin-cell format. Simultaneous cycling of a large number of cells is further enabled by a compact and low cost (~ 38 USD per jig) pressure application jig of which 100 have been constructed to date. The utility of these advances is demonstrated through a brief study on the effect cathode-side conductive carbon and current collector type has on capacity and rate performance.

25 ENERGY STORAGE↗

Mode I fracture testing fixture

An apparatus and method for preparing Double Cantilever Beam (DCB) specimens are disclosed as an apparatus and method for conducting Mode I fracture resistance testing using the DCB specimens. In a first embodiment, a drill jig is used to locate the DCB specimen and guide a drilling process during creation of at least one through-hole in the DCB specimen. The drilling process may employ a traditional drill and drill bit, a laser drill, or a water jet. In another embodiment, a set of rotating pin blocks, each with a full-round or a half-round specimen pin at one end and a hanger full-round pin at the other end, engage the DCB specimen and facilitate the internal application of a fracturing load to the DCB specimen for the Mode I fracture resistance test. The present invention may significantly reduce the time and materials needed to prepare and test a DCB specimen.

Briggs, Timothy↗

Mode I fracture testing fixture

An apparatus and method for preparing Double Cantilever Beam (DCB) specimens are disclosed as an apparatus and method for conducting Mode I fracture resistance testing using the DCB specimens. In a first embodiment, a drill jig is used to locate the DCB specimen and guide a drilling process during creation of at least one through-hole in the DCB specimen. The drilling process may employ a traditional drill and drill bit, a laser drill, or a water jet. In another embodiment, a set of rotating pin blocks, each with a full-round or a half-round specimen pin at one end and a hanger full-round pin at the other end, engage the DCB specimen and facilitate the internal application of a fracturing load to the DCB specimen for the Mode I fracture resistance test. The present invention may significantly reduce the time and materials needed to prepare and test a DCB specimen.

Briggs, Timothy↗

Universal test fixture for monolithic mm-wave integrated circuits calibrated with an augmented TRD algorithm

The design and evaluation of a novel fixturing technique for characterizing millimeter wave solid state devices is presented. The technique utilizes a cosine-tapered ridge guide fixture and a one-tier de-embedding procedure to produce accurate and repeatable device level data. Advanced features of this technique include nondestructive testing, full waveguide bandwidth operation, universality of application, and rapid, yet repeatable, chip-level characterization. In addition, only one set of calibration standards is required regardless of the device geometry.

Romanofsky, Robert R.↗

Development of a Compact, Low Cost Test Fixture to Evaluate Creep in High Strength Softgoods Materials under Constant Environmental Control

Space exploration is typically driven by two key factors: cost and payload mass. Therefore creating relatively low cost, low mass space hardware is critical. With the advancement of new high-strength flexible materials, a new chapter is opening in the evolution of pressurized space structures. Space-rated inflatable structures are attractive due to their low mass, compact stowage, and capability of performing as well, or better than, their rigid counterparts for applications such as habitats and airlocks. The lifetime properties of materials used for inflatable structures are not as well characterized as heritage composite and metallic materials; therefore, they require extensive testing to increase the level of confidence in their use. Creep testing is one method of evaluating the expected lifetime of materials that may be under constant load for many years in operational use. Conventional creep testing of high-strength softgoods webbings or cordage requires a large, temperature-controlled facility, with structural frames capable of supporting large dead weights, weighing thousands of pounds on each specimen. This is expensive and takes up a significant amount of volume in a facility for a long time. This paper describes the design and analysis of a low-cost, low-volume creep test stand that can be locally environmentally controlled, so that smaller, cheaper facilities can be used for characterizing the creep life of the softgoods materials used in inflatable space structures.

Softgoods↗

Characterization of Radiation Heat Transfer in High Temperature Structural Test Fixtures

The paper looks at the radiant heat exchange between some fairly primitive geometry components, and a few more complex, to understand the radiant energy distribution under a very common radiant lamp consisting of 6 quartz tube (tungsten element) heaters. This is looking at the basic physics of a common device used around the world for many decades. Other papers have looked at this same topic, but ours is looking at other topics we have not seen addressed in the literature (that explain why it is what it is, and other things affecting data interpretation).

structures testing↗

Design and Preliminary Experimental Results on a Uniform-Field Test Fixture for Power Flow Experiments

Electrodes that produce a uniform electric field across their surfaces are desired for a variety of high-voltage systems including spark-gap switches and transversely excited atmospheric lasers. Here, the implementation of uniform-field electrodes to a parallel-plate load is described for the study of vacuum power flow under pulsed-power applications. We begin with an overview of general uniform-field geometries, and provide an open-source program that generates these geometries as described by Ernst. Following that, a modification to an existing power-flow experimental platform, that adopts a uniform-field geometry, is introduced and its utility is described. Lastly, preliminary experimental results are presented and future steps are outlined.

Capacitors↗

Universal test fixture for solar cells

Coverings for solar cells are evaluated conveniently with alumina ceramic circuit board holding three pairs of cells and three field-effect translator (FET) chips overlaid with candidate encapsulant. With fixture, solar cells and encapsulants are exposed to Sunlight and weather, either natural or artificial, to provide pertinent measurement and performance data.

Kolyer, J. M.↗

Electrostatic forming and testing of polymer films on a 16-foot diameter test fixture

The large space systems technology program investigated different forms of large, lightweight, deployable structures which could be carried on the Space Shuttle. Different forms and concepts of antennas as a type of large space system were investigated. The electrostatically controlled membrane reflector made of metallized material concept was chosen. The concept is a good candidate for creating an antenna with high surface quality and has the ability to be packaged and deployed from the Shuttle with a significant reduction in weight compared to other antenna types.

Goslee, J. W.↗