Manufacturing & Prototyping

Improved Blackbody Temperature Sensors for a Vacuum Furnace

Through proper selection of materials, it is possible to satisfy severe requirements.

Some improvements have been made in the design and fabrication of blackbody sensors (BBSs) used to measure the temperature of a heater core in a vacuum furnace. Each BBS consists of a ring of thermally conductive, high-melting-temperature material with two tantalum-sheathed thermocouples attached at diametrically opposite points. The name “blackbody sensor” reflects the basic principle of operation. Heat is transferred between the ring and the furnace heater core primarily by blackbody radiation, heat is conducted through the ring to the thermocouples, and the temperature of the ring (and, hence, the temperature of the heater core) is measured by use of the thermocouples.

Posted in: Briefs, Manufacturing & Prototyping, Measurements, Sensors and actuators, Sensors and actuators, Heat transfer, Heat transfer, Performance upgrades, Thermal testing

Thin-Film Solid Oxide Fuel Cells

Mass, volume, and the cost of materials can be reduced for a given power level.

The development of thin-film solid oxide fuel cells (TFSOFCs) and a method of fabricating them have progressed to the prototype stage. A TFSOFC consists of the following:

Posted in: Briefs, Manufacturing & Prototyping, Fuel cells, Product development, Fabrication

Novel Materials Containing Single-Wall Carbon Nanotubes Wrapped in Polymer Molecules

Coating carbon nanotubes in polymer molecules creates a new class of materials with enhanced mechanical properties for printed circuit boards, antenna arrays, and optoelectronics.

In this design, single-wall carbon nanotubes (SWNTs) have been coated in polymer molecules to create a new type of material that has low electrical conductivity, but still contains individual nanotubes, and small ropes of individual nanotubes, which are themselves good electrical conductors and serve as small conducting rods immersed in an electrically insulating matrix. The polymer is attached through weak chemical forces that are primarily non-covalent in nature, caused primarily through polarization rather than the sharing of valence electrons. Therefore, the electronic structure of the SWNT involved is substantially the same as that of free, individual (and small ropes of) SWNT. Their high conductivity makes the individual nanotubes extremely electrically polarizable, and materials containing these individual, highly polarizable molecules exhibit novel electrical properties including a high dielectric constant.

Posted in: Briefs, Manufacturing & Prototyping

Light-Curing Adhesive Repair Tapes

Adhesive resins in tapes are rigidized in place by exposure to light.

Adhesive tapes, the adhesive resins of which can be cured (and thereby rigidized) by exposure to ultraviolet and/or visible light, are being developed as repair patch materials. The tapes, including their resin components, consist entirely of solid, low-out-gassing, nonhazardous or minimally hazardous materials. They can be used in air or in vacuum and can be cured rapidly, even at temperatures as low as –20 °C. Although these tapes were originally intended for use in repairing structures in outer space, they can also be used on Earth for quickly repairing a wide variety of structures. They can be expected to be especially useful in situations in which it is necessary to rigidize tapes after wrapping them around or pressing them onto the parts to be repaired.

Posted in: Briefs, Manufacturing & Prototyping, Maintenance, Repair and Service Operations, Maintenance, repair, and service operations, Adhesives and sealants, Resins

Zinc Alloys for the Fabrication of Semiconductor Devices

Materials improve the performance of semiconductor devices.

ZnBeO and ZnCdSeO alloys have been disclosed as materials for the improvement in performance, function, and capability of semiconductor devices. The alloys can be used alone or in combination to form active photonic layers that can emit over a range of wavelength values.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Materials properties, Semiconductors, Zinc alloys

Two-Step Plasma Process for Cleaning Indium Bonding Bumps

This process could increase yields in the manufacture of consumer electronic products.

A two-step plasma process has been developed as a means of removing surface oxide layers from indium bumps used in flip-chip hybridization (bump bonding) of integrated circuits. This process has considerable commercial potential in that flip-chip hybridization is used in the manufacture of cellular telephones and other compact, portable electronic products.

Posted in: Briefs, Manufacturing & Prototyping

Tool for Crimping Flexible Circuit Leads

A hand tool has been developed for crimping leads in flexible tails that are parts of some electronic circuits — especially some sensor circuits. The tool is used to cut the tails to desired lengths and attach solder tabs to the leads. For tailoring small numbers of circuits for special applications, this hand tool is a less expensive alternative to a commercially available automated crimping tool. The crimping tool consists of an off-the-shelf hand crimping tool plus a specialized crimping insert designed specifically for the intended application.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Connectors and terminals, Connectors and terminals, Customization, Tools and equipment

Improved Assembly for Gas Shielding During Welding or Brazing

Inert gas is distributed evenly over the region surrounding the weld joint.

An improved assembly for inert-gas shielding of a metallic joint is designed to be useable during any of a variety of both laser-based and traditional welding and brazing processes. The basic purpose of this assembly or of a typical prior related assembly is to channel the flow of a chemically inert gas to a joint to prevent environmental contamination of the joint during the welding or brazing process and, if required, to accelerate cooling upon completion of the process.

Posted in: Briefs, Manufacturing & Prototyping, Manufacturing equipment and machinery, Welding, Gases

Fabricating PFPE Membranes for Microfluidic Valves and Pumps

This process contributes to development of “laboratory-on-a-chip” devices.

A process has been developed for fabricating membranes of a perfluoropolyether (PFPE) and integrating them into valves and pumps in “laboratory-on-a-chip” microfluidic devices. Membranes of poly(tetrafluoroethylene) [PTFE] and poly(dimethylsilane) [PDMS] have been considered for this purpose and found wanting. By making it possible to use PFPE instead of PTFE or PDMS, the present process expands the array of options for further development of microfluidic devices for diverse applications that could include detection of biochemicals of interest, detection of toxins and biowarfare agents, synthesis and analysis of proteins, medical diagnosis, and synthesis of fuels.

Posted in: Briefs, Manufacturing & Prototyping

Fabricating PFPE Membranes for Capillary Electrophoresis

Precisely sized and positioned holes are defined by photomasks.

A process has been developed for fabricating perfluoropolyether (PFPE) membranes that contain microscopic holes of precise sizes at precise locations. The membranes are to be incorporated into “laboratory-on-a-chip” microfluidic devices to be used in performing capillary electrophoresis.

Posted in: Briefs, Manufacturing & Prototyping

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