Home

Low-Density Titanium-Based Bulk Metallic Glasses with High Glass-Forming Ability

These materials can be used in gears, bearings, latches, inserts, and sheet metal. NASA’s Jet Propulsion Laboratory, Pasadena, California Ti-based bulk metallic glasses (BMGs) and matrix composites (BMGMCs) are a subset of the class of materials known synonymously as amorphous metals, liquid metals, and glassy metals, described by their majority element (in atomic percent) being that of titanium. BMGs are non-crystalline metal alloys based in a wide variety of elemental systems, including zirconium, iron, nickel, hafnium, gold, platinum, palladium, and silver, among others. The vast majority of commercially utilized BMGs are based in Zr-Ti-Cu-Ni-Be or Zr-Cu-Ni-Al due to their relatively low-cost elements and large glass-forming ability (GFA), typically greater than 1 cm. BMGs have long been considered to be a material without a clear application, as the density of BMGs fits squarely between two common, highperformance crystalline alloys that BMGs are usually thought to be replacements for: steel (density = 7.8 g/cm3) and titanium (density = 4.5 g/cm3). For example, Zr-based BMGs generally fit into the range of 6 to 6.5 g/cm3, which makes them difficult to use as direct replacements for conventional materials.

Posted in: Briefs

Read More >>

Thermal Management Coating (TMC)

The coating uses micro-encapsulated phase-change material. Marshall Space Flight Center, Alabama An experimental study was conducted in conjunction with the research and development program at the NASA Marshall Space Flight Center (MSFC) on thermal protection systems (TPS) for aerospace applications, a new concept for reusable TPS material. The new system uses a micro-encapsulated phase-change material rather than an ablative material to dissipate the heat produced during supersonic flight. This new material absorbs energy as it goes through a phase change during the heating portion of the flight profile and then the energy is released as the material cools. This new TPS consists of micro-encapsulated phasechange material and a resin system to adhere the coating to the structure. The technology has been successfully tested in the hot gas tunnel (aero-thermal heating). The figure shows the test results.

Posted in: Briefs

Read More >>

AeroHeating Tools (AHT) Suite

Lyndon B. Johnson Space Center, Houston, Texas This suite of computer programs, called “tools,” is used to calculate local flow angles over damage sites in the Shuttle Orbiter Thermal Protection System (TPS). It provides a quick and easy way to compute cross flow angles over points of interest on the Shuttle Orbiter TPS.

Posted in: Briefs

Read More >>

EXOS Software

Lyndon B. Johnson Space Center, Houston, Texas An improved version of EXOS software allows for the modeling of fabrics, mixtures, and porous materials, and also provides the ability to accept hex mesh geometries. The code employs a novel numerical method, a hybrid particle finite element approach, as well as particles and elements in tandem, each modeling distinct aspects of the physics. Ellipsoidal particles are used to model contact-impact and volumetric thermomechanical response (Euler parameters provide a singularity-free description of particle rotations). Elements are used to model “strength” effects; namely, tensile inter-particle forces and elastic-plastic deviatoric deformation.

Posted in: Briefs, TSP, Electronics & Computers, Coatings & Adhesives

Read More >>

Using Paraffin Phase Change Material to Make Optical Communication-Type Payloads Thermally Self-Sufficient for Operation in Orion Crew Module

Goddard Space Flight Center, Greenbelt, Maryland The Orion Crew Module has a pressurized cabin of approximately 20 m3 in volume. There are a number of cold plates within the Crew Module for thermal management. An optical communication type of payload consists of electronics boxes and modems that dissipate a significant amount of heat during science operation. Generally, such payloads operate for a short term (e.g., up to one hour). If these heat-dissipating components are flown inside the Crew Module, they require heat rejection to the cold plates in the Crew Module. The waste heat is transported from the cold plate to thermal radiators located outside the Orion spacecraft. This makes such a payload thermally dependent on the Crew Module cold plates.

Posted in: Briefs, TSP

Read More >>

Aerogel-Filled Foam Core Insulation for Cryogenic Propellant Storage

Advanced cryogenic insulation has applications in energy, medicine, food storage and packaging, and electronics. Marshall Space Flight Center, Alabama Current cryogenic insulation materials suffer from various drawbacks including high cost and weight, lack of structural or load-bearing capability, fabrication complexity, and property anisotropy. A need clearly exists for lightweight thermal insulation that is isotropic and structurally capable with high thermal performance, while also offering reduced fabrication and installation complexity, and lower cost.

Posted in: Briefs

Read More >>

Multifunctional B/C Fiber Composites for Radiation Shielding

Marshall Space Flight Center, Alabama A versatile, novel, multifunctional hybrid structural composite of a high-hydrogen epoxy matrix (UN-10) coupled with boron and carbon fibers (IM-7) has been developed. Prototype laminates of 18×18 in. (≈46×46 cm), with the nominal areal density of 0.35 g/cm2, were fabricated in this effort. The hydrogen atoms in the epoxy will provide shielding strength against high-energy protons, electrons, and heavy ionic species, while the boron fibers that have a high neutron cross-section will help shield against neutrons and reduce the buildup of high-energy photons from secondary reactions. The carbon fibers will provide improved mechanical strength.

Posted in: Briefs

Read More >>

The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.