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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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At least 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Space station structures and dynamics test program

The design, construction, and operation of a low-Earth orbit space station poses challenges for development and implementation of technology. One specific challenge is the development of a dynamics test program for defining the space station design requirements, and identifying and characterizing phenomena affecting the space station's design and development. The test proposal, as outlined, is a comprehensive structural dynamics program to be launched in support of the space station (SS). Development of a parametric data base and verification of the mathematical models and analytical analysis tools necessary for engineering support of the station's design, construction, and operation provide the impetus for the dynamics test program. The four test phases planned are discussed: testing of SS applicable structural concepts; testing of SS prototypes; testing of actual SS structural hardware; and on-orbit testing of SS construction.

Bugg, Frank M.↗
NASA NTRS1987

Space Station Mission Planning System (MPS) development study. Volume 1: Executive summary

The basic objective of the Space Station (SS) Mission Planning System (MPS) Development Study was to define a baseline Space Station mission plan and the associated hardware and software requirements for the system. A detailed definition of the Spacelab (SL) payload mission planning process and SL Mission Integration Planning System (MIPS) software was derived. A baseline concept was developed for performing SS manned base payload mission planning, and it was consistent with current Space Station design/operations concepts and philosophies. The SS MPS software requirements were defined. Also, requirements for new software include candidate programs for the application of artificial intelligence techniques to capture and make more effective use of mission planning expertise. A SS MPS Software Development Plan was developed which phases efforts for the development software to implement the SS mission planning concept.

Klus, W. J.↗
NASA NTRS1987

Space Station Mission Planning Study (MPS) development study. Volume 3: Software development plan

A software development plan is presented for the definition, design, and implementation of the Space Station (SS) Payload Mission Planning System (MPS). This plan is an evolving document and must be updated periodically as the SS design and operations concepts as well as the SS MPS concept evolve. The major segments of this plan are as follows: an overview of the SS MPS and a description of its required capabilities including the computer programs identified as configurable items with an explanation of the place and function of each within the system; an overview of the project plan and a detailed description of each development project activity breaking each into lower level tasks where applicable; identification of the resources required and recommendations for the manner in which they should be utilized including recommended schedules and estimated manpower requirements; and a description of the practices, standards, and techniques recommended for the SS MPS Software (SW) development.

Klus, W. L.↗
NASA NTRS1989

Study of metal corrosion using ac impedance techniques in the STS launch environment

AC impedance measurements were performed to investigate the corrosion resistance of 19 alloys under conditions similar to the STS launch environment. The alloys were: Zirconium 702, Hastelloy C-22, Inconel 625, Hastelloy C-276, Hastelloy C-4, Inconel 600, 7Mo + N, Ferralium 255, Inco Alloy G-3, 20Cb-3, SS 904L, Inconel 825, SS 304LN, SS 316L, SS 317L, ES 2205, SS 304L, Hastelloy B-2, and Monel 400. AC impedance data were gathered for each alloy after one hour immersion time in each of the following three electrolyte solutions: 3.55 percent NaCl, 3.55 percent NaCl-0.1N HCl, and 3.55 percent NaCl-1.0N HCl. The data were analyzed qualitatively using the Nyquist plot and quantitatively using the Bode plot. Polarization resistance, Rp, values were obtained using the Bode plot. Zirconium 702 was the most corrosion resistant alloy in the three electrolytes. The ordering of the other alloys according the their resistance to corrosion varied as the concentration of hydrochloric acid in the electrolyte increased. The corrosion resistance of Zirconium 702 and Ferralium 255 increased as the concentration of hydrochloric acid in the electrolyte increased. The corrosion resistance of the other 17 alloys decreased as the concentration of the hyrdochloric acid in the electrolyte increased.

Calle, Luz M.↗
NASA NTRS1993

Interaction of various mechanical activity models in regulation of myosin heavy chain isoform expression

The purpose of this study was to determine the effects of a novel combination of mechanical activity paradigms on the isomyosin distribution in rat hindlimb muscles. Thirty female Sprague-Dawley rats were divided into five experimental groups as follows: normal control, functional overload (OV) of the plantaris, OV in conjunction with hindlimb suspension (OV-S), and a combination of OV-S and either static standing weight-bearing activity (OV-SS) or high-incline treadmill exercise (OV-SE). OV of the plantaris resulted in significant hypertrophy and significant fast-to-slow isomyosin shifts. These changes were completely inhibited by the addition of hindlimb suspension (OV-S). Also, neither of the two weight-bearing regimes (OV-SS and OV-SE) was able to attenuate the suspension-induced atrophy. In the vastus intermedius and vastus lateralis, however, OV-SS was able to partially retard the atrophy associated with suspension. In both the plantaris and vastus intermedius, only OV-SS was able to partially reverse the slow-to-fast isomyosin transitions associated with suspension. These results suggest that the type of mechanical activity is important in determining adaptation to altered loading conditions, with OV-SS appearing more effective than OV-SE in reversing the effects of unweighting.

Diffee, Gary M.↗
NASA NTRS1994

Technology transfer and evaluation for Space Station telerobotics

The international space station (SS) must take advantage of advanced telerobotics in order to maximize productivity and safety and to reduce maintenance costs. The Automation and Robotics Division at the NASA Lyndon B. Johnson Space Center (JSC) has designed, developed, and constructed the Automated Robotics Maintenance of Space Station (ARMSS) facility for the purpose of transferring and evaluating robotic technology that will reduce SS operation costs. Additionally, JSC had developed a process for expediting the transfer of technology from NASA research centers and evaluating these technologies in SS applications. Software and hardware system developed at the research centers and NASA sponsored universities are currently being transferred to JSC and integrated into the ARMSS for flight crew personnel testing. These technologies will be assessed relative to the SS baseline, and, after refinements, those technologies that provide significant performance improvements will be recommended as upgrades to the SS. Proximity sensors, vision algorithms, and manipulator controllers are among the systems scheduled for evaluation.

Price, Charles R.↗
NASA NTRS2002

The Evolution of Disks and Winds in Dwarf Nova Outbursts - FUSE

This project was a project to study the FUV spectra of two proto-typical dwarf novae, U Gem and SS Cygni, through an outburst cycle. The luminosity of the boundary layer in the two systems, as evidenced by earlier EUVE observations, is different in the two systems. Our intensive study of the two systems was intended to (1) probe the ionization and kinematic structure of the wind as a function of system brightness, (2) isolate the contributions of the disk to the FUV spectra, and (3) examine physical conditions and abundances of material just being accreted onto the disk from the secondary. The U Gem and SS Cyg observations took place in March and October 2000, respectively. The data obtained with FUSE was of excellent quality. Analysis of the both observations is now essentially complete, although some modeling of the SS Cyg spectra is ongoing, as we complete an ApJ manuscript on this object. Our main results for U Gem are as follows: The plateau spectra have continuum shapes and fluxes that are approximated by steady state accretion disk model spectra with an accretion rate 7x10(exp 9) Msolar/yr. The spectra also show numerous absorption lines of H I, He II, and 2-5 times ionized transitions of C, N, O, P, S, and Si. There are no emission features in the spectra, with the possible exception of a weak feature on the red wing of the 0 VI doublet. The absorption lines are narrow (FWHM approx. 50 km/s), too narrow to arise from the disk photosphere, and at low velocities (less than or equal to 700 km/s). The S VI and O VI doublets are optically thick. The absorption lines in the plateau spectra show orbital variability: in spectra obtained at orbital phases between 0.53 and 0.79, low-ionization absorption lines appear and the central depths of the preexisting lines increase. The increase in line absorption occurs at the same orbital phases as previously observed EUV and X-ray light-curve dips. If the absorbing material is in (near-) Keplerian rotation around the disk, it must be located at large disk radii. The final observation occurred when U Gem was about 2 mag from optical quiescence. The spectra are dominated by emission from an approx. 43,000 K, metal-enriched white dwarf (WD). The inferred radius of the WD is 4.95x10(exp 8) cm, close to that observed in quiescence. Allowing for a hot heated region on the surface of the WD improves the fit to the spectrum at short (less than 960 A) wavelengths. Our main results for SS Cyg are as follows: The first two of four observations of SS Cyg show disk dominated spectra with accretion rates of order 10(exp -8) Msolar/yr. Except for narrow interstellar features (atomic and molecular H), the lines are all broad consistent with a disk or wind origin. The O VI line in the spectra is mostly of wind origin as detailed modeling with our Monte Carlo code (developed in part using funds from this project) show. The continua from spectra in observations 3 and 4, observed during the decline phase, are not well fit with steady-state disks, and show considerable resemblance to quiescent spectra obtained with HUT. The most probable interpretation for the emission features seen in the spectrum in the last two observations is that they arise from a photo-illuminated choronosphere above the disk, rather than a wind.

Long, Knox↗
NASA NTRS2004

Corrosion Performance of Stainless Steels in a Simulated Launch Environment

At the Kennedy Space Center, NASA relies on stainless steel (SS) tubing to supply the gases and fluids required to launch the Space Shuttle. 300 series SS tubing has been used for decades but the highly corrosive environment at the launch pad has proven to be detrimental to these alloys. An upgrade with higher alloy content materials has become necessary in order to provide a safer and long lasting launch facility. In the effort to find the most suitable material to replace the existing AISI 304L SS ([iNS S30403) and AISI 316L SS (UNS S31603) shuttle tubing, a study involving atmospheric exposure at the corrosion test site near the launch pads and electrochemical measurements is being conducted. This paper presents the results of an investigation in which stainless steels of the 300 series, 304L, 316L, and AISI 317L SS (UNS S31703) as well as highly alloyed stainless steels 254-SMO (UNS S32154), AL-6XN (N08367) and AL29-4C ([iNS S44735) were evaluated using direct current (DC) electrochemical techniques under conditions designed to simulate those found at the Space Shuttle Launch pad. The electrochemical results were compared to the atmospheric exposure data and evaluated for their ability to predict the long-term corrosion performance of the alloys.

Calle, Luz Marina↗
NASA NTRS2011

From Space Weather Toward Space Climate Time Scales: Substorm Analysis from 1993 to 2008

Magnetic activity in the Northern Hemisphere auroral region was examined during solar cycles 22 and 23 (1993- 2008). Substorms were identified from ground-based magnetic field measurements by an automated search engine. On average, 550 substorms were observed per year, which gives in total about 9000 substorms. The interannual, seasonal and solar cycle-to-cycle variations of the substorm number (R(sub ss)), substorm duration (T(sub ss)), and peak amplitude (A(sub ss)) were examined. The declining phases of both solar cycles 22 and 23 were more active than the other solar cycle phases due to the enhanced solar wind speed. The spring substorms during the declining solar cycle phase (absolute value of A(sub ss,decl)) - 500 nT) were 25% larger than the spring substorms during the ascending solar cycle years ((absolute value of A(sub ss,asc) = 400 nT). The following seasonal variation was found: the most intense substorms occurred during spring and fall, the largest substorm frequency in the Northern Hemisphere winter, and the longest-duration substorms in summer. Furthermore, we found a winter-summer asymmetry in the substorm number and duration. which is speculated to be due to the variations in the ionospheric conductivity. The solar cycle-Io-cycle variation was found in the yearly substorm number and peak amplitude. The decline from the peak substorm activity in 1994 and 2003 to the following minima took 3 years during solar cycle 22, while it took 6 years during solar cycle 23.

Tanskanen, E. I.↗
DOE OSTI2022

Corrosion of Stainless and Carbon Steel in Aqueous Piperazine for CO2 Capture

Current obstacles that prevent commercial implementation of amine-scrubbing CO2 capture are the high costs. Reducing capital costs by appropriate selection of construction materials, which requires knowledge of material corrosion performance for the process, will improve the economic feasibility of this technology. Corrosion was evaluated in three pilot plant campaigns using aqueous piperazine with the Advanced Stripper (PZAS). 316L stainless steel (SS) experienced higher corrosion than 304 SS and 2205 duplex SS, and the corrosion rate showed strong dependence on the temperature. 304 and 2205 performed well at all locations and should be good construction materials for PZAS. Degraded PZ exacerbated 316L corrosion, and removal of PZ degradation products using a carbon adsorption bed significantly reduced corrosion. Carbon steel (CS) corrosion showed a weak temperature effect because the corrosion was more dependent on the protective siderite film. The protectiveness of the films was related to fluid velocity. Ni-based alloys corroded in PZ, and the rate increased with temperature. Corrosion of C1010 CS and SS (304, 316L, 430) was measured at absorber and water wash conditions on the bench-scale. Corrosion rate decreases with increasing PZ. 8 With more than 0.003 m PZ in solution, CS has acceptable corrosion performance. Corrosion of CS increases with increasing partial pressure of CO2, suggesting loading is another dominant parameter for carbon steel corrosion. Temperature has a less significant effect than PZ concentration and loading. CS corrosion increases with increasing flow velocity at both absorber and water wash conditions. SS had little corrosion at this lower temperature. Performance of siderite (FeCO3) protective films on CS was studied at representative stripper conditions on the bench-scale. Siderite films can deposit on the surface of CS in CO2-loaded PZ solution at temperatures >100 °C and protect CS from corrosion. The protection may fail in degraded PZ. Ethylenediamine (EDA) is one of the major contributors for the loss of film protectiveness or can be the surrogate for the effect of PZ degradation on siderite film protection. A link between protectiveness and the apparent density of siderite films was discovered. The apparent density of siderite films decreases with increasing flow velocity and decreasing CO2 loading, resulting in higher corrosion of CS.

Liu, Ching-Ting↗
DOE OSTI2024

Dislocation channel broadening–A new mechanism to improve irradiation-assisted stress corrosion cracking resistance of additively manufactured 316 L stainless steel

Additively manufactured (AM) 316 L stainless steel (SS) after hot isostatic pressing (HIP) was found to exhibit superior resistance to irradiation-assisted stress corrosion cracking (IASCC) in high-temperature water, as compared to wrought 316 L SS. The well-accepted IASCC factors of radiation-induced segregation (RIS) and radiation hardening are not accurate descriptions of IASCC susceptibility in this case. A decreased strain localization along grain boundaries, caused by dislocation channel broadening, was confirmed to suppress crack initiation. A unique distribution of irradiation-induced defects in HIP AM 316 L SS eased dislocation cross-slip compared to those in the wrought counterpart, thus increasing the channel width near the grain boundaries. Here for the first time, this study highlights the importance of dislocation channel broadening as a potential mechanism to further improve the IASCC resistance of 316 L SS and provides direct experimental evidence based on commercial-grade materials.

316L stainless steel↗
DOE OSTI2025

Long-term thermal aging behavior and strength reduction in a laser powder bed fusion 316H stainless steel

The long-term thermal stability of structural alloys is essential for ensuring the safe and reliable operation of nuclear reactors and other power plants. While extensive research has explored the effects of thermal aging on conventional stainless steels, the behavior of additively manufactured (AM) alloys remains less understood. This study examines the thermal aging response of laser powder bed fusion (LPBF) 316H stainless steel (SS) at temperatures ranging from 550 °C to 750 °C over durations of up to 10,000 h (approximately 1.14 years). Advanced characterization techniques, including electron microscopy and synchrotron X-ray diffraction, were used to investigate dislocation recovery and phase evolution. Based on these findings, a time-temperature-precipitation (TTP) diagram was developed for LPBF 316H SS, revealing a 10- to100-fold acceleration in precipitation kinetics compared to wrought 316H SS. A physics-informed model was calibrated using the short-term experimental data, enabling predictions of average precipitate sizes, volume fractions of M 23 C 6 and Laves phases, and changes in molybdenum solute concentration for aging up to 1 × 10⁶ h (114 years). These microstructural insights were further utilized to estimate yield strength and extrapolate strength reduction factors over the extended aging period. Despite the accelerated aging kinetics, LPBF 316H SS demonstrated superior yield strength retention compared to its wrought counterpart. In conclusion, this study establishes a framework for evaluating long-term performance using short-term experimental data and supports the accelerated qualification of AM materials for high-temperature structural applications.

Laser powder bed fusion↗
DOE OSTI2022

Wet-chemical synthesis of Li7P3S11 with tailored particle size for solid state electrolytes

The small-size solid-state electrodes (SSEs) with high Li+ conductivity play an important role in reducing the interfacial resistance between electrode materials and SSEs and defects between SSEs. As one of the most conductive sulfide based ionic conductors, scalable synthesis of Li7P3S11 with controllable particle sizes is highly desired but rarely reported. Here, we report a facile wet-chemical synthesis method to prepare Li7P3S11 SSEs with variable sizes for all-solid-state lithium batteries (ASSLBs). By fully dissolving 70Li2S-30P2S5 precursors in ethyl acetate solution, the particle size of Li7P3S11 can be manipulated into as small as ~110 nm and high Li+ conductivity of 1.05 mS cm-1 can be achieved. A systematical mechanistic study of solvent effects suggests that the controlled particle sizes are attributed to the excellent solvability and low binding energy of ethyl acetate solvent toward solutes. Moreover, this generic method can be extended to the facilely synthesis of Li3PS4 nanoparticles with an average size of ~200 nm and high Li+ conductivity of 0.1 mS cm-1.

Zhou, Jianbin↗
DOE OSTI2023

High-temperature chromium diffusion in austenitic stainless steel: Ab initio molecular dynamics simulations

Chromium self-diffusion through stainless steel (SS) matrix and along grain boundaries is an important mechanism controlling SS structural materials corrosion. For this work, Cr diffusion in austenitic SS was simulated using canonical ab initio molecular dynamics with realistic models of type-316 SS bulk, with and without Cr vacancies, and a low-energy Σ3 twin boundary typically observed at active corrosion sites. Cr self-diffusion coefficients at 750 and 850 °C calculated using Einstein’s diffusion equation are 4.2 × 10 –6 and 8.1 × 10 –6 Å 2 ps –1 in pristine bulk, 3.8 × 10 –3 and 5.5 × 10 –3 Å 2 ps –1 in bulk including Cr vacancies, and 9.5 × 10 –2 and 1.0 × 10 –1 Å 2 ps –1 at a Σ3[1 1 1]60° twin boundary.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Safety perceptions of solid-state lithium metal batteries

Safety concerns hamper the wide application of lithium-ion batteries (LIBs) in the fields of electric vehicles and stationary energy storage. As the blame of the battery thermal runway was widely cast on the flowable, volatile, and flammable nature of liquid organic electrolytes, solid-state lithium batteries with solid and nonflammable electrolytes are highly praised for potentially better safety characteristics. Furthermore, solid-state lithium metal batteries (SS-LMBs) may become an ultimate solution for safe, high-energy density batteries. Whether SS-LMBs are safe enough to meet emerging demands remains unclear, as recent publications have presented serious safety concerns at both the material and device levels. In conclusion, this review summarizes recent investigations into SS-LMB safety, and systematic analysis and discussion are provided in this discussion of the safety concerns of SS-LMBs.

25 ENERGY STORAGE↗
DOE OSTI2025

Investigation of MO x (M = Cr, Mn, Re, and Mo) coated stainless-steel electrodes for oxygen evolution reaction in natural seawater electrolysis

Seawater electrolysis is considered a potential strategy for large-scale of affordable H 2 production. However, poor durability of the anode for oxygen evolution reaction (OER) in natural seawater is a remaining concern due to chloride-induced reaction. Herein, the effect of various MO x (M = Mn, Cr, Re, and Mo) coated stainless steel (SS) electrodes on OER in direct natural seawater electrolysis was comprehensively studied. It is found that the Mo-coated SS electrode is superior to all others in terms of durability, followed by Re-coated SS, while the Cr and Mn-coated SS electrodes show the poorest durability. Additionally, the durability and activity of the Mo/SS electrode can be boosted remarkably in 1 M KOH/seawater compared to the natural seawater, resulting in an overpotential at 10 mA cm −2 decrease from 830 to 399 mV. Meanwhile, no degradation is observed at 1000 mA cm −2 for 100 h in 1 M KOH seawater, which is among the best stability, based on the literature review. Moreover, the improved durability and activity with Mo coating were extended to the Inconel 718 substrate, and around 40 % improvement in durability and 25 mV overpotential decrease at 10 mA cm −2 are observed, which indicates that Mo coating can be considered as a universal approach to improve the anode durability and activity. The improved performance with Mo coating may be attributed to the continuous Mo oxide layer formation or in situ generated MoO 4 2− in the OER process. In conclusion, this work provides a holistic strategy to enhance the anode durability and activity under harsh conditions, offering valuable insights for designing corrosion-resistant electrodes in direct seawater electrolysis.

Direct seawater electrolysis↗
DOE OSTI2021

Effect of heat treatment on creep behavior of 316 L stainless steel manufactured by laser powder bed fusion

The objective of this study is to understand the thermal stability of microstructure and its effect on the creep behavior of additively-manufactured 316L stainless steel (AM 316L SS). Creep specimens were fabricated from rods printed by a laser powder bed fusion process. Six different heat treatments, namely 650 °C/1 h, 700 °C/1 h, 750 °C/1 h, 800 °C/1 h, 900 °C/1 h and 1050 °C/1 h were applied to the creep specimens. The heat-treated specimens were creep-tested under the same condition, 550 °C/275 MPa to evaluate the effect of post-build heat treatment on the creep behavior of AM 316L SS. In the temperature range of 650-750 °C, dislocation density within cells, and cell size and wall thickness were affected by the heat treatment, while elemental segregation at boundaries remained unchanged and Mn-enriched Si oxide particles remained stable. In the temperature range of 750-900 °C, concurrent changes were observed in dislocation cell structures, elemental segregation and oxide particles. The 1050 °C-heat treatment removed cell structures and boundary solute segregations, leading to formation of equiaxed grains; Mn-enriched Si oxide particles in the as-built specimen were replaced by more stable Mn-enriched Cr oxides. The creep life of AM 316L SS increased after the heat treatment at 650 °C and then decreased with increasing temperature up to 900 °C where cell/subgrain structures still existed. The creep rate and creep elongation followed an opposite trend. The creep rate can be correlated with the structural parameters of cell/subgrain size and cell wall/boundary thickness and can be rationalized by different strengthening mechanisms of dislocation cells and subgrains. The heat treatment affected strongly the primary and secondary creep but had a minimal effect on the tertiary creep of AM 316L SS.

316L stainless steel↗