EVAPORATION EFFECTS ON MATERIALS IN SPACE
Vacuum environmental effects on the evaporation, sublimation and decomposition rates of materials for space application
SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Vacuum environmental effects on the evaporation, sublimation and decomposition rates of materials for space application
Material composition, weight, size, and unfolding factors entering into design of inflatable space station structures
A continuing research objective of the National Aeronautical and Space Administration (NASA) is to develop advanced composite materials for space structures. The thrust of this research is to gain fundamental understanding of the performance of advanced composites in the space environment. The emphasis has been to identify and model changes in the thermal-physical properties due to induced damage and develop improved materials.
NASA Glenn Research Center (Glenn) has 39 individual materials flight experiments (>540 samples) flown as part of the Materials International Space Station Experiment (MISSE) to address long duration environmental durability of spacecraft materials in low Earth orbit (LEO). MISSE is a series of materials flight experiments consisting of trays, called Passive Experiment Carriers (PECs) that are exposed to the space environment on the exterior of the International Space Station (ISS). MISSE 1-5 have been successfully flown and retrieved and were exposed to the space environment from one to four years. MISSE 6A & 6B were deployed during the STS-123 shuttle mission in March 2008, and MISSE 7A & 7B are being prepared for launch in 2009. The Glenn MISSE experiments address atomic oxygen (AO) effects such as erosion and undercutting of polymers, AO scattering, stress effects on AO erosion, and in-situ AO fluence monitoring. Experiments also address solar radiation effects such as radiation induced polymer shrinkage, stress effects on radiation degradation of polymers, and radiation degradation of indium tin oxide (ITO) coatings and spacesuit fabrics. Additional experiments address combined AO and solar radiation effects on thermal control films, paints and cermet coatings. Experiments with Orion Crew Exploration Vehicle (CEV) seals and UltraFlex solar array materials are also being flown. Several experiments were designed to provide ground-facility to in-space calibration data thus enabling more accurate in-space performance predictions based on ground-laboratory testing. This paper provides an overview of Glenn s MISSE 1-7 flight experiments along with a summary of results from Glenn s MISSE 1 & 2 experiments.
Summaries are presented for the first group of materials processing experiments planned for a shuttle mission. Outlined are the objectives, the approach, the rationale for the use of space, and the anticipated results for each experiment.
A variety of materials consisting of polyimides, polyethylene terephthalates (PETs), fiber reinforced polymers, and polyhedral oligomeric silsesquioxanes (POSS) were on the exterior of the International Space Station (ISS) as part of Materials International Space Station Experiment (MISSE)-16. Samples on the side of the ISS pointing in the direction of the spacecraft’s motion (the ram direction) were observed for effects due to atomic oxygen (AO). The erosion yield of select materials from MISSE-16 is reported, as well as their variation in surface roughness due to AO erosion. Trade names and trademarks are used in this paper for identification only. Their usage does not constitute an official endorsement, either expressed or implied, by the National Aeronautics and Space Administration.
Thermionic materials for space power application
Identification of volatile contaminants of space cabin materials
Acceptance criteria of space materials, discussing materials for surveyor
Surface analysis by electron spectroscopy for chemical analysis (ESCA) was used to characterize a number of the material samples for the space telescope. With ESCA, the sample is irradiated with monoenergetic soft X-rays and the resulting emitted electrons are energy analyzed to determine the binding energy of electrons to the surface atoms. The major peaks were used in the quantitative determination of the surface composition. The presence of trace elements (impurities below 1% atomic composition) was also detailed. Initially a survey scan was run for each sample to deduce the elemental composition. Then the major peaks of interest and those of the trace elements were individually examined. After this, the samples were argon sputtered to etch away surface layers, and then additional measurements were carried out in order to obtain depth profile information. In this way it was possible for those species present only on the surface to be distinguished from those having a significant depth distribution within the sample.
The stability of the polycyclic aromatic hydrocarbon (PAH) coronene has been studied under conditions representing those in interstellar space. It is concluded that although polycyclic aromatic material can survive in diffuse clouds, it is rapidly destroyed after accretion on interstellar dust in dense clouds. This limits the lifetime of such material in space to less than or equal to 5 x 10(exp 7) years.
Thermionic materials for space power application - uranium carbide-zirconium carbide fuels and tungsten cladding
This work will encompass the preflight characterization of 15 novel and heritage materials currently under observation on the Materials International Space Station Experiment-Flight Facility (MISSE-FF). MISSE-FF has been upgraded to perform active reflectance measurements of the materials. Images taken in RGB/IR colors are compared to results from an extensive ground testing campaign to obtain quantitative on-orbit material evolution data. Identical materials samples are to be flown on the ram, wake, and zenith faces of MISSE-FF, enabling deconvolution of the energetic electron, proton, atomic oxygen, and ultraviolet damage pathways. Energy deposition from the space environment leads to chemical changes in the material that in turn alter the optical properties. The same chemical damage that manifests as changes in optical reflectance and absorptance also leads to changes in myriad physical properties such as mechanical strength, electrical conductivity, and chemical reactivity. Therefore, flight materials are able to be characterized based on their unique reflectance spectra by comparing on-orbit measurements of optical reflectance with extensive terrestrial experiments, which help to correlate changes in reflectance with respect to changes in other material properties. The MISSE program has been a part of the International Space Station National Laboratory for many years and has been instrumental in understanding space weather modification of material properties. However, MISSE-FF has been limited to passive experiments with only pre/post flight material studies possible. In advance of the MISSE-16 experiment, the flight facility has received a major upgrade to provide daily spectral observations by way of a RGB/IR camera and a tunable light source. The MISSE-16 mission launched in February 2022 and carries 15 material samples for 6 months of the low Earth orbital exposure. Identical materials samples are to be flown on the ram, wake, and zenith faces of MISSE-FF, enabling deconvolution of the energetic electron, proton, atomic oxygen, and ultraviolet damage pathways. This paper discusses the MISSE-16 experiment, highlights the first use of the facility upgrades, and presents results from the extensive preflight material characterization that includes directional hemispherical reflectance, bidirectional reflectance, AFM, SEM, and electrical conductivity. Additionally, data showing the modification of these properties by ground-based exposure to space-like electron and atomic oxygen flux will be discussed. Finally, updates on deployment and initial check-out of the experiment on MISSE-FF will be presented. It is the ultimate goal of this program to provide validation for the development of ground based space weather simulation facilities and techniques.
In recent years, a great deal of research has been exerted to developing NDE methods for the characterization of the material properties of composites as well as other space structural materials. The need for information about such parameters as the elastic properties, density, and thickness are critical to the safe design and operation of such structural materials. Ultrasonics using immersion methods has played an important role in these efforts due to its capability, cost effectiveness, and ease of use. The authors designed a series of ultrasonic oblique insonification experiments in order to develop a practical field applicable NDE method for space structures.
To develop and test new materials for use in space power systems and related space and commercial applications, to assist industry in the application of these materials, and to achieve an adequate understanding of the mechanisms by which the materials perform in their intended applications.
The design, construction, and materials used in the Apollo space suit are discussed. The various materials and combinations of materials to obtain the desired type of protection are identified. Detailed descriptions are provided of the pressure garment, liquid cooled garment, extravehicular gloves, helmet, and boots.
Encapsulation of radioactive source materials for long period space flights
Fibrous, cellulosic, elastomeric and plastic materials with improved flame resistant properties for space applications