Determination of parameters necessary for the prediction of ablative heat protection.
Ablative heat protection prediction of material response and environmental factors for ground- based test information
ABLATING MATERIAL↗
SEARCH · Engineering Papers
Results for “ENVIRONMENTAL MATERIALS”
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.
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The developments in modifying functionality of lignin and its application in biocomposites
With the advancement of sustainable material innovations, renewable natural biopolymers are gradually replacing traditional metal and petroleum-based synthetic materials due to their environmental friendliness, biodegradability, and economic advantages. Lignin, the second most abundant natural aromatic polymer in the plant kingdom, has emerged as a key candidate raw material for the development of green polymer systems because of its unique phenylpropane unit network structure, high carbon content, and rich functional group characteristics. However, challenges such as the inherent structural complexity, chemical inertness, and uneven molecular weight distribution of lignin limit its direct application. By employing modification strategies such as chemical functionalization and physical regulation, researchers can precisely control its reactivity, thermal stability, and interfacial compatibility, enabling the preparation of high-performance lignin-based functional composites. Here, this paper systematically reviews the principles and methodological advancements in lignin's multi-dimensional modification technology. It analyzes the mechanisms by which various chemical and physical modification techniques enhance the mechanical properties, functional responsiveness, and environmental adaptability of materials, and discusses innovative applications in fields such as intelligent packaging, biomedical materials, and energy storage devices. Furthermore, this review addresses the key challenges encountered in the high-value transformation of lignin, with the aim of offering a theoretical framework and technical pathway for the transformative development of lignin from agricultural and forestry by-products to functional material platforms.
Functional composites↗
Thick-film materials for silicon photovoltaic cell manufacture
Thick film technology is applicable to three areas of silicon solar cell fabrication; metallization, junction formation, and coating for protection of screened ohmic contacts, particularly wrap around contacts, interconnection and environmental protection. Both material and process parameters were investigated. Printed ohmic contacts on n- and p-type silicon are very sensitive to the processing parameters of firing time, temperature, and atmosphere. Wrap around contacts are easily achieved by first printing and firing a dielectric over the edge and subsequently applying a low firing temperature conductor. Interconnection of cells into arrays can be achieved by printing and cofiring thick film metal pastes, soldering, or with heat curing conductive epoxies on low cost substrates. Printed (thick) film vitreous protection coatings do not yet offer sufficient optical uniformity and transparency for use on silicon. A sprayed, heat curable SiO2 based resin shows promise of providing both optical matching and environmental protection.
Field, M. B.↗
Exploring Coupled Extreme Environments via In-situ Transmission Electron Microscopy
In-situ transmission electron microscopy (TEM) provides an avenue to explore time-dependent nanoscale material changes induced by a wide range of environmental conditions that govern material performance and degradation. The In-situ Ion Irradiation TEM (I 3 TEM) at Sandia National Laboratories is a JEOL 2100 microscope that has been highly modified with an array of hardware and software that makes it particularly well suited to explore fundamental mechanisms that arise from coupled extreme conditions. Here, examples pertaining to multibeam ion irradiation, rapid thermal cycling, and nanomechanical testing on the I 3 TEM are highlighted, along with prospective advancements in the field of in-situ microscopy.
47 OTHER INSTRUMENTATION↗
Life cycle cost assessment of material recovery from perovskite solar cells
Perovskite photovoltaic (PV) cells have created a significant interest over the last few years due to their low-cost and high-power conversion efficiencies. While perovskite PVs are still under development, we analyze cost of alternative sustainable end-of-life management for perovskite PV cells; this allows to reuse economically valuable materials and prevent environmental contamination. Here, we studied the life cycle cost assessment of recovering metals such as lead, aluminum, gold, nickel, and silver and other valuable materials such as glass from waste perovskite PVs. We also developed a recycling scheme to optimize the material recovery and determine the economically feasible ways to separate the cells layer-by-layer. Further, we assessed the cost and the net cost of the perovskite PV recycling processes. We found that the most feasible recycling technique’ cost is $\$$10.70 and its net cost is $\$$– 2.95 per 1 m 2 module. These values could be further improved by optimizing and reusing chemicals involved in process. These results indicate that the cost of perovskite PV recycling is economically feasible and there is potentional to gain benefit from sustainable end-of-life management of perovskite PVs.
14 SOLAR ENERGY↗
First-principles calculations with machine learning modeling to predict high-temperature gas sensing materials
This talk introduced our research on developing sensing materials for harsh environmental applications. By combining first-principles density functional theory simulations with AI/ML approach, we have established a sensor database which can predict candidate materials at given operating conditions.
density functional theory (DFT)↗
Materials technology development for long life large space systems
Large Space Systems materials requirements are discussed in terms of types of materials, critical properties, and environmental stability. An outline is given of the materials technology development that will be needed to meet these requirements.
Gause, R. L.↗
The Use of Pristine and Intercalated Graphite Fiber Composites as Buss Bars in Lead-Acid Batteries
This study was conducted as a part of the Firefly Energy Space Act Agreement project to investigate the possible use of composite materials in lead acid batteries. Specifically, it examined the use of intercalated graphite composites as buss bars. Currently, buss bars of these batteries are made of lead, a material that is problematic for several reasons. Over time, the lead is subject to both corrosion at the positive plate and sulfation at the negative plate, resulting in decreased battery life. In addition, the weight and size of the lead buss bars make for a heavy and cumbersome battery that is undesirable. Functionality and practicality of lead buss bars is adequate at best; consequently, investigation of more efficient composite materials would be advantageous. Practically speaking, graphite composites have a low density that is nearly one fourth that of its lead counterpart. A battery made of less dense materials would be more attractive to the consumer and the producer because it would be light and convenient. More importantly, low weight would be especially beneficial because it would result in greater overall power density of the battery. In addition to power density, use of graphite composite materials can also increase the life of the battery. From a functional standpoint, corrosion and sulfation at the positive and negative plates are major obstacles when considering how to extend battery life. Neither of these reactions are a factor when graphite composites replace lead parts because graphite is chemically non-reactive with the electrolyte within the battery. Without the problem of corrosion or sulfation, battery life expectancy can be almost doubled. The replacement of lead battery parts with composite materials is also more environmentally favorable because of easy disposal of organic materials. For this study, both pristine and bromine intercalated single-ply graphite fiber composites were created. The composites were fabricated in such a way as to facilitate their use in a 3" x 1/2" buss bar test cell. The prime objective of this investigation was to examine the effectiveness of a variety of graphite composite materials to act as buss bars and carry the current to and from the positive and negative battery plates. This energy transfer can be maximized by use of materials with high conductivity to minimize the buss resistance. Electrical conductivity of composites was measured using both a contactless eddy current probe and a four point measurement. In addition, the stability of these materials at battery-use conditions was characterized.
Opaluch, Amanda M.↗
Combined-Accelerated Stress Testing of Photovoltaic Materials
By applying multiple environmental stresses in fieldrepresentative combinations and sequences, combined-accelerated stress testing (CAST) identifies degradation modes and failure mechanisms of photovoltaic (PV) modules and components that are missed by single stress factor accelerated testing.
14 SOLAR ENERGY↗
Aerospace applications of advanced aluminum alloys
Advanced metallic materials within the Al-base family are being developed for applications on current and future aerospace vehicles. These advanced materials offer significant improvements in density, strength, stiffness, fracture resistance, and/or higher use temperature which translates into improved vehicle performance. Aerospace applications of advanced metallic materials include space structures, fighters, military and commercial transport aircraft, and missiles. Structural design requirements, including not only static and durability/damage tolerance criteria but also environmental considerations, drive material selections. Often trade-offs must be made regarding strength, fracture resistance, cost, reliability, and maintainability in order to select the optimum material for a specific application. These trade studies not only include various metallic materials but also many times include advanced composite materials. Details of material comparisons, aerospace applications, and material trades will be presented.
Chellman, D. J.↗
Origins of Irreversibility in Layered NaNi x Fe y Mn z O 2 Cathode Materials for Sodium Ion Batteries
Layered NaNi x Fe y Mn z O 2 cathode (NFM) is of great interest in sodium ion batteries due to its high theoretical capacity and utilization of abundant, low-cost, environmentally-friendly raw materials. Nevertheless, there remains insufficient understanding on the concurrent local environment evolution in each transition metal (TM) that largely influences the reversibility of the cathode materials upon cycling. In this work, we investigate the reversibility of TM ions in layered NFMs with varying Fe contents and potential windows. Utilizing ex situ synchrotron X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure (EXAFS) of pre-cycled samples the valence and bonding evolution of the TMs are elucidated. It is found that Mn is electrochemically inactive as indicated by the insignificant change of Mn valence and Mn-O bonding distance. Fe is electrochemically inactive after the first five cycles. The Ni redox couple contributes most of the charge compensation for NFMs. Ni redox is quite reversible in the cathodes with less Fe contents. Furthermore, the Ni redox couple shows significant irreversibility with high Fe content of 0.8. The electrochemical reversibility of the NFM cathode becomes increasingly enhanced with the decrease of either Fe content or with lower upper charge cutoff potential.
25 ENERGY STORAGE↗
Autonomous System for MISSE Temperature Measurements
The Materials International Space Station Experiment (MISSE) is scheduled to be deployed during the summer of 2001. This experiment is a cooperative endeavor by NASA-LaRC, NASA-GRC, NASA MSFC, NASA-JSC, the Materials Laboratory at the Air Force Research Laboratory, and the Boeing Phantom Works. The objective of the experiment is to evaluate performance, stability, and long term survivability of materials and components planned for use by NASA and DOD on future LEO, synchronous orbit, and interplanetary space missions. Temperature is an important parameter in the evaluation of space environmental effects on materials.
Harvey, G. A.↗
MISSE 1 and 2 Tray Temperature Measurements
The Materials International Space Station Experiment (MISSE 1 & 2) was deployed August 10,2001 and retrieved July 30,2005. This experiment is a co-operative endeavor by NASA-LaRC. NASA-GRC, NASA-MSFC, NASA-JSC, the Materials Laboratory at the Air Force Research Laboratory, and the Boeing Phantom Works. The objective of the experiment is to evaluate performance, stability, and long term survivability of materials and components planned for use by NASA and DOD on future LEO, synchronous orbit, and interplanetary space missions. Temperature is an important parameter in the evaluation of space environmental effects on materials. The MISSE 1 & 2 had autonomous temperature data loggers to measure the temperature of each of the four experiment trays. The MISSE tray-temperature data loggers have one external thermistor data channel, and a 12 bit digital converter. The MISSE experiment trays were exposed to the ISS space environment for nearly four times the nominal design lifetime for this experiment. Nevertheless, all of the data loggers provided useful temperature measurements of MISSE. The temperature measurement system has been discussed in a previous paper. This paper presents temperature measurements of MISSE payload experiment carriers (PECs) 1 and 2 experiment trays.
Harvey, Gale A.↗
Techno‐economic, environmental, and social measurement of clean energy technology supply chains
Abstract In addition to the criteria of reliability and cost, clean energy technologies, such as wind, solar, and batteries, need to strive to a higher standard of environmental and societal benefit along their entire supply chain. This means additional performance metrics for these technologies should be considered, such as embodied energy, embodied carbon, recycled content and recyclability, environmental impact of material sourcing, impact on land and ecosystems, materials recovery at end of life, and production through quality nonexploitive jobs with community benefit. Many commercial and emerging energy technologies have not yet been explicitly evaluated based on these environmental and social performance metrics, which presents multiple opportunities for researchers and analysts. In this paper, we review the importance and current limitations of techno‐economic and life‐cycle assessment models for research design and manufacturing decisions. We explore emerging manufacturing modeling options that could improve environmental and social performance and how they could be used to help guide research. Even with the deployment of low‐carbon energy‐generation technologies, the future of a successful clean energy transition requires collaboration between researchers, advanced manufacturers, independent standards and tracking organizations, local communities, and national governments, to ensure the financial, environmental, and social sustainability of the entire supply and manufacturing process of energy technologies.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
Characterization of Cracking and Crack Growth Properties of the C5A Aircraft Tie-Box Forging
Detailed destructive examinations were conducted to characterize the integrity and material properties of two aluminum alloy (7075-T6) horizontal stabilizer tie box forgings removed.from US. Air Force C5A and C5B transport aircraft. The C5B tie box forging was,found to contain no evidence of cracking. Thirteen cracks were found in the CSA,forging. All but one of the cracks observed in the C5A component were located along the top cap region (one crack was located in the bottom cap region). The cracks in the C5A component initiated at fastener holes and propagated along a highly tunneled intergranular crack path. The tunneled crack growth configuration is a likelv result of surface compressive stress produced during peening of the .forging suijace. The tie box forging ,fatigue crack growth, fracture and stress corrosion cracking (SCC) properties were characterized. Reported herein are the results of laboratory air ,fatigue crack growth tests and 95% relative humidity SCC tests conducted using specimens machined from the C5A ,forging. SCC test results revealed that the C5A ,forging material was susceptible to intergranular environmental assisted cracking: the C5A forging material exhibited a SCC crack-tip stress-intensity factor threshold of less than 6 MPadn. Fracture toughness tests revealed that the C5A forging material exhibited a fracture toughness that was 25% less than the C5B forging. The C5A forging exhibited rapid laboratory air fatigue crack growth rates having a threshold crack-tip stress-intensity factor range of less than 0.8 MPa sup m. Detailed fractographic examinations revealed that the ,fatigue crack intergranular growth crack path was similar to the cracking observed in the C5A tie box forging. Because both fatigue crack propagation and SCC exhibit similar intergranular crack path behavior, the damage mechanism resulting in multi-site cracking of tie box forgings cannot be determined unless local cyclic stresses can be quantified.
Piascik, Robert S.↗
Stress Corrosion Evaluation of NiTiHf Alloy for the International Space Station Environmental Control and Life Support System
A stress corrosion evaluation was performed on NiTiHf alloy because this material is considered a bearing material candidate for the Environmental Control and Life Support System. Stressed round tensile specimens survived exposures to alternate pretreat, alternate brine, baseline pretreat, baseline brine, and 3.5% NaCl alternate immersion. Metallographic evaluations did not detect stress corrosion on exposed samples. The ultimate tensile strength values varied significantly for this material, which is common for bearing materials. This variation was observed on both, exposed and nonexposed specimens. The results of this work indicate that this material has potential applications as a bearing material.
International Space Station (ISS)↗
The Surge of Metal–Organic-Framework (MOFs)-Based Electrodes as Key Elements in Electrochemically Driven Processes for the Environment
Metal–organic-frameworks (MOFs) are emerging materials used in the environmental electrochemistry community for Faradaic and non-Faradaic water remediation technologies. It has been concluded that MOF-based materials show improvement in performance compared to traditional (non-)faradaic materials. In particular, this review outlines MOF synthesis and their application in the fields of electron- and photoelectron-Fenton degradation reactions, photoelectrocatalytic degradations, and capacitive deionization physical separations. This work overviews the main electrode materials used for the different environmental remediation processes, discusses the main performance enhancements achieved via the utilization of MOFs compared to traditional materials, and provides perspective and insights for the further development of the utilization of MOF-derived materials in electrified water treatment.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Enhancing CMC Temperature Performance in High Hydrogen Environments using Field Assisted Sintering Technology
This final report summarizes the developments in field assisted sintering technology (FAST) for rapid fabrication of ceramic matrix composite (CMC) materials with integrated environmental barrier coatings (EBCs), as well as their performance in a representative gas turbine combustor environment including stagnant flame zones, and high velocity product zones. CMCs are a possible high temperature tolerant material system for gas turbine engines, which are currently the dominant source of electric power production and the primary source of aircraft propulsion. However, CMCs are costly and time-consuming (on the order of weeks to months) to fabricate, and CMCs based on silicon carbide (SiC) ceramics are susceptible to water vapor degradation requiring the use of specialized EBCs. The manufacturing technique known as FAST can create consolidated parts in as little as a few hours using high pressure and temperature, and may be useful to integrate EBCs into CMCs directly during consolidation.
08 HYDROGEN↗