Materials

Bulk Metallic Glasses and Composites for Optical and Compliant Mechanisms

This innovation has uses in the aerospace, optics, bio-implants, spacecraft, and sporting equipment industries. Mechanisms are used widely in engineering applications due to their ability to translate force and movement. They are found in kinematic pairs, gears, cams, linkages, and in flexure mechanisms (also known as compliant mechanisms). Mechanisms and flexures are used widely in spacecraft design, especially in the area of optics, where precise positioning of telescope mirrors requires elastic flexing of elements. A compliant mechanism is generally defined as a flexible mechanism that uses an elastic body deformation to cause a displacement (such as positing a mirror). The mechanisms are usually constructed as a single monolithic piece of material, and contain thin struts to allow for large elastic bending with low input force. This creates the largest problem with developing precise mechanisms; they must be fabricated from a single piece of metal, but are required to have strict accuracy on their dimensions. They are generally required to have high strength, elasticity, and low coefficient of thermal expansion.

Posted in: Materials, Briefs

Read More >>

Film-Forming, Self- Crosslinking, Aqueous Superabsorbent Coating

This air-curable material absorbs and holds liquids, vapors, and proteins for applications in healthcare, wound care, packaging, textiles, and engineering. Aqueous Superabsorbent Coating (ASC) technology is a liquid polymer solution that dries to form an absorbent film. It can absorb up to 40 g/g by weight of water, depending on the chemistry used, and can absorb water vapor from the air up to 70% by weight. Tests have demonstrated a greater absorbency of fluids containing proteins than cross-linked sodium polyacrylates (ASC 8-10g/g versus SAP 6g/g). The material can be “dried” after hydrolysis with exposure to air at moderate temperature.

Posted in: Materials, Briefs

Read More >>

Non-Toxic, Anti-Corrosive, Crystalline Waterproofing Material

This material prevents concrete deterioration by preventing water and other corrosives from getting to the reinforcing steel. This product is an efficient concrete waterproofing solution. The crystalline, anti-corrosive material features a patented eka-molecular-sieve structure. The cement-based material works with the matrix of cement and water to create crystals that block the pores and capillaries in the concrete, making it impervious to water and corrosives. The material cures within 24 hours without any special ventilation. It continues to penetrate into the substrate as long as water is present. It will lay dormant in the substrate for years without the presence of water; however, if water attempts to enter at a future date through hairline cracks, the chemicals once again will become active and block the passage of water, creating a self-healing capability.

Posted in: Materials, Briefs

Read More >>

Applications for Gradient Metal Alloys Fabricated Using Additive Manufacturing

A new roadmap for gradient metals that could be used in cars, optics, aircraft, and sporting goods. Recently, additive manufacturing (AM) techniques have been developed that may shift the paradigm of traditional metal production by allowing complex netshaped hardware to be built up layer-by-layer, rather than being machined from a billet. The AM process is ubiquitous with polymers due to their low melting temperatures, fast curing, and controllable viscosity, and 3D printers are widely available as commercial or consumer products. 3D printing with metals is inherently more complicated than with polymers due to their higher melting temperatures and reactivity with air, particularly when heated or molten. The process generally requires a high-power laser or other focused heat source, like an electron beam, for precise melting and deposition. Several promising metal AM techniques have been developed, including laser deposition (also called laser engineered net shaping or LENS® and laser deposition technology (LDT)), direct metal laser sintering (DMLS), and electron beam free-form (EBF). These machines typically use powders or wire feedstock that are melted and deposited using a laser or electron beam. Complex net-shape parts have been widely demonstrated using these (and other) AM techniques and the process appears to be a promising alternative to machining in some cases.

Posted in: Materials, Briefs

Read More >>

Ambient Dried Aerogels

A method has been developed for creating aerogel using normal pressure and ambient temperatures. All spacecraft, satellites, and landers require the use of thermal insulation due to the extreme environments encountered in space and on extraterrestrial bodies. Ambient dried aerogels introduce the possibility of using aerogel as thermal insulation in a wide variety of instances where supercritically dried aerogels cannot be used. More specifically, thermoelectric devices can use ambient dried aerogel, where the advantages are in situ production using the cast-in ability of an aerogel.

Posted in: Materials, Briefs

Read More >>

Passivation of Flexible YBCO Superconducting Current Lead With Amorphous SiO2 Layer

The aim of this project is to design and construct leads from YBCO composite conductors to reduce the heat load to adiabatic demagnetization refrigerators. Adiabatic demagnetization refrigerators (ADR) are operated in space to cool detectors of cosmic radiation to a few 10s of mK. A key element of the ADR is a superconducting magnet operating at about 0.3 K that is continually energized and de-energized in synchronism with a thermal switch, such that a piece of paramagnetic salt is alternately warm in a high magnetic field and cold in zero magnetic field. This causes the salt pill or refrigerant to cool, and it is able to suck heat from an object, e.g., the sensor, to be cooled. Current has to be fed into and out of the magnets from a dissipative power supply at the ambient temperature of the spacecraft. The current leads that link the magnets to the power supply inevitably conduct a significant amount of heat into the colder regions of the supporting cryostat, resulting in the need for larger, heavier, and more powerful supporting refrigerators. The aim of this project was to design and construct high-temperature superconductor (HTS) leads from YBCO (yttrium barium copper oxide) composite conductors to reduce the heat load significantly in the temperature regime below the critical temperature of YBCO.

Posted in: Materials, Briefs, TSP

Read More >>

Reliability Testing of GORE® Protective Vents in Telecommunication Enclosures

Premature failure of telecommunication equipment leads to network downtime, higher costs, increased maintenance and decreased brand loyalty. One of the most significant challenges for this equipment is withstanding the conditions of the environment in which it is installed.

Posted in: Materials, White Papers

Read More >>

White Papers

3D Visualization: The Key to Improving Time to Market for High-Tech Products
Sponsored by SAP
10 Ways to Make Your Wiring and Harness Design Faster and Better
Sponsored by Mentor Graphics
Oscilloscope Fundamentals
Sponsored by Rohde and Schwarz A and D
Next-Generation, Miniature High Voltage Power Modules
Sponsored by EMCO High Voltage
Fundamentals of Vector Network Analysis Primer
Sponsored by Rohde and Schwarz A and D
Antenna Basics
Sponsored by Rohde and Schwarz

White Papers Sponsored By: