Search

Mechanical and Fluid Systems
Improved Lunar Regolith Simulant Ion Implantation
Researchers and other technology developers require regolith simulants that accurately emulate the properties of lunar, Martian, and asteroid soils to ensure that the processes, devices, tools, and sensors being developed will be usable in an active mission environment. To move toward higher fidelity regolith simulants, NASA has developed a system that takes typical regolith simulants and implants ions of relevant elements to better simulate the conditions of extraterrestrial soils. The ion implantation device developed here is composed of three key elements as shown in the figure below: two hopper and rotary valve elements and the acceleration grid structure. To perform the ion implantation, the system is first placed within a vacuum chamber, pumped down, and gases of the elements of interest are pumped into the chamber. The system then first passes a mass of granulated lunar regolith simulant through two stages of hoppers and rotary valves to condition the material. Key to the system is a process for interstitial gas removal (a source of contamination) as shown in the figure on the right. After conditioning, the regolith simulant is passed between two parallel electrodes under a high voltage, accelerating ions of the process gas and implanting those ions within the regolith simulant at controllable depths. The related patent is now available to license. Please note that NASA does not manufacturer products itself for commercial sale.
Materials and Coatings
Durable Anti-Icing Coatings
Low ice adhesion strength coatings are only useful insofar as they remain on the surface of interest, and aircraft leading edges experience extreme environmental conditions during flight. Ensuring durability while maintaining performance – in this case, reduction of impact (i.e., accreted in-flight) ice adhesion strength – is critical to meeting the needs of the aviation industry and other commercial applications. To that end, NASA engineers investigated coating compositions comprised of epoxy resins, including aromatic and aliphatic resins, and aromatic diamine hardeners. Several nonreactive additives were incorporated and tested. The first was holey graphene, a unique nanomaterial made by partly oxidizing areas of graphene that already have defects. This creates high energy functionalities that result in good dispersion throughout the matrix, enabling the mechanical properties of graphene to be imparted throughout the coating. Secondly, micrometer-sized core-shell rubber particles were dispersed throughout the epoxy resin to increase toughness. Finally, a series of polyhedral oligomeric silsequixones (POSS) were used for mechanical reinforcement. Several different coating formulations were development and tested, each incorporating different relative amounts of additives, with good results. Thus, the coatings can be tailored to meet different application-specific requirements. NASA's coating formulations, with further development, may be suitable for in-flight (i.e., impact) ice adhesion reduction on aircraft leading edges and other platforms exposed to harsh environments.
Materials and Coatings
Water filtration cartridge flow-through illustration
Graphene Loading Method for Water Filtration Media
NASA and the US Army Engineer Research and Development Center (ERDC) co-developed advanced graphene materials designed to improve the filtration rate of spacecraft water contaminants which could significantly extend the service life of existing media filtration beds. Traditional granulated activated carbon (GAC) media is characterized by having a polymodal pore structure and contains micro-, meso-, and macropores that trap and contain contaminants. By using the referenced method to add graphene nanoparticles to an existing GAC filtering substrate, additional filtering can be achieved due to graphene’s mostly mesoporous nature. A high-level overview of the graphene loading process is thus: The unloaded graphene nanoparticles are mixed with a water-based graphene suspension for an extended time at room temperature. This “graphene bath” process is repeated several times before the now graphene-loaded (up to ~ 1% by mass) filtration media is dried and prepared for packing into a filter cartridge. The graphene suspension used during the loading process may be reused multiple times, reducing consumables in the process. Laboratory testing has shown a 40x improvement in contaminant removal per mass of the absorbent (i.e., graphene) over the state of the art (granulated activated carbon) at lower loading rates, suggesting significant promise of the treated filter media posing a potential solution to the demands of an entire mission lifecycle. Potential commercial applications for this graphene loading method may lay in four distinct market segments that rely on filtration media beds (outside of aerospace): industrial filtration such as ultra-pure water refining for the semiconductor industry, commercial filtration, residential filtration, and filtration-as-a-service. Graphene nano-particles’ tunable pore sizing, in conjunction with this loading method, could offer tailored filtration boosting for existing water filter substrates. The Graphene Loading Method for Water Filtration Media has a technology readiness level (TRL) 4 (Component and/or breadboard validation in laboratory environment), and it is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.
Stay up to date, follow NASA's Technology Transfer Program on:
facebook twitter linkedin youtube
Facebook Logo X Logo Linkedin Logo Youtube Logo