Manufacturing & Prototyping

Ultrasonic Low-Friction Containment Plate for Thermal and Ultrasonic Stir Weld Processes

The thermal stir welding (TSW) process is finding applications in fabrication of space vehicles. In this process, workpieces to be joined by TSW are drawn, by heavy forces, between “containment plates,” past the TSW tool that then causes joining of the separate plates. It is believed that the TSW process would be significantly improved by reducing the draw force, and that this could be achieved by reducing the friction forces between the workpieces and containment plates.

Posted in: Manufacturing & Prototyping, Briefs

Read More >>

High-Powered, Ultrasonically Assisted Thermal Stir Welding

This method has the potential to increase the longevity of hardware in the auto industry, especially in bearing wear. This method is a solid-state weld process capable of joining metallic alloys without melting. The weld workpieces to be joined by thermal stir welding (TSW) are drawn, by heavy forces, between containment plates past the TSW stir tool that then causes joining of the weld workpiece.

Posted in: Manufacturing & Prototyping, Briefs

Read More >>

Next-Generation MKIII Lightweight HUT/Hatch Assembly

Applications for general aviation include the insulation around fuel tanks, especially winglocated tanks. The MK III (H-1) carbon-graphite/ epoxy Hard Upper Torso (HUT)/Hatch assembly was designed, fabricated, and tested in the early 1990s. The spacesuit represented an 8.3 psi (≈58 kPa) technology demonstrator model of a zero prebreathe suit. The basic torso shell, brief, and hip areas of the suit were composed of a carbon-graphite/epoxy composite lay-up. In its current configuration, the suit weighs approximately 120 lb (≈54 kg). However, since future planetary suits will be designed to operate at 0.26 bar (≈26 kPa), it was felt that the suit’s redesigned weight could be reduced to 79 lb (≈35 kg) with the incorporation of lightweight structural materials.

Posted in: Manufacturing & Prototyping, Briefs, TSP

Read More >>

Additive Manufactured Propulsion System (AMPS) for Small to Micro Cubical Satellites

A hybrid, single-part design was fabricated from a material that acts as both the structure and the fuel for the propulsion system. The use of additive manufacturing technologies in aerospace applications has presented both opportunities and challenges. The ability to produce parts and components using additive manufacturing holds promise in both metals and plastics, whereas traditional subtractive manufacturing can be restrictive in design development and material selection.

Posted in: Manufacturing & Prototyping, Briefs

Read More >>

Bismuth Passivation Technique for High-Resolution X-Ray Detectors

The Athena-plus team requires X-ray sensors with energy resolution of better than one part in 3,000 at 6 keV X-rays. While bismuth is an excellent material for high X-ray stopping power and low heat capacity (for large signal when an X-ray is stopped by the absorber), oxidation of the bismuth surface can lead to electron traps and other effects that degrade the energy resolution. Bismuth oxide reduction and nitride passivation techniques analogous to those used in indium passivation are being applied in a new technique. The technique will enable improved energy resolution and resistance to aging in bismuth- absorber-coupled X-ray sensors.

Posted in: Manufacturing & Prototyping, Briefs, TSP

Read More >>

Silicon Micromachined Microlens Array for THz Antennas

There is strong demand for a multi-pixel heterodyne detector array for Earth observation, astrophysics, future planetary, and ground applications. A 5×5 silicon microlens array was developed using a silicon micromachining technique for a silicon-based THz antenna array. The feature of the silicon micromachining technique enables one to microfabricate an unlimited number of microlens arrays at one time with good uniformity on a silicon wafer. This technique will resolve one of the key issues in building a THz camera, which is to integrate antennas in a detector array. The conventional ap proach of building single-pixel receivers and stacking them to form a multi-pixel receiver is not suited at THz because a single-pixel receiver already has difficulty fitting into mass, volume, and power budgets, especially in space applications.

Posted in: Manufacturing & Prototyping, Briefs, TSP

Read More >>

Method for Reduction of Silver Biocide Plating on Metal Surfaces

Silver ions in aqueous solutions (0.05 to 1 ppm) are used for microbial control in water systems. The silver ions remain in solution when stored in plastic containers, but the concentration rapidly decreases to non-biocidal levels when stored in metal containers. The silver deposits onto the surface and is reduced to non-biocidal silver metal when it contacts less noble metal surfaces, including stainless steel, titanium, and nickel-based alloys.

Posted in: Manufacturing & Prototyping, Briefs

Read More >>