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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

CNN-Based Phase Fault Classification in Real and Simulated Power Systems Data

This study proposes a convolutional neural network (CNN)–based two-step phase fault detection and identification method to classify anomalies in the power grid signal. Specifically, the first step checks the fault’s existence and determines the need for the second step. Subsequently, in the case of anomalies in the power grid signal, the second step identifies the type of fault, including line-to-line, single-line-to-ground, double-line-to-ground, and triple-line. Accordingly, the CNN architecture is both designed for the classification layers and trained with simulated data. To provide maximum prediction accuracy with minimum processing time, this study investigates the combinations of various feature extraction (FE) techniques, such as fast Fourier transform (FFT), amplitude and phase (AP), auto-correlation function, power spectral density, and wavelet transform (WT). Consequently, simulated and real-world results demonstrate that the proposed two-step method outperforms conventional one-step techniques, with the best performance obtained by using the combination of AP-AP, AP-WT, FFT-AP, and FFT-WT–based FE methods.

Alaca, Ozgur↗
DOE OSTI2026

FY26 Progress Report on the Operation of the Activated Materials Laboratory at the Advanced Photon Source as a Nuclear Science User Facilities Partner Facility

The Activated Materials Laboratory (AML), located in the Long Beamline Building of the Advanced Photon Source (APS) at Argonne National Laboratory (ANL), provides a centralized radiological capability for preparing, handling, and supporting synchrotron experiments on activated materials. As a Nuclear Science User Facilities (NSUF) partner facility, the AML enables the receipt of radioactive shipments, open-form sample handling, encapsulation, transport of specimens to and from APS beamlines, and experimentation with dedicated equipment. The partnership includes the APS 1-ID and 20-ID beamlines, which provide high-energy x-ray scattering, tomography, and diffraction microscopy techniques for ex-situ, in-situ, and grainresolved three-dimensional (3D) characterization. All samples supported through the AML and partner beamlines must meet radiological limits of less than 100 mrem/h at 30 cm. This FY26 progress report summarizes the first full year of AML operations as an NSUF partner facility and highlights progress in both user support and capability development. By the end of FY26, the AML had received a total of 10 NSUF-awarded projects, including 2 Consolidated Innovative Nuclear Research (CINR), 7 Rapid Turnaround Experiment (RTE), and 1 Super RTE projects. Beamtime was fully delivered for 3 RTE projects and partially delivered for 1 CINR project, demonstrating successful workflows for receipt, encapsulation, beamline transfer, and radiological experiment execution. These efforts demonstrated safe radiological experiments at APS beamlines for samples with dose rates above the historical 5 mrem/h threshold and now up to 100 mrem/h at 30 cm, marking an important milestone for neutron-irradiated materials research. During FY26, the AML also expanded its experimental capabilities. A Psylotech xTS load frame with in-grip rotation was deployed for room-temperature mechanical testing with threedimensional x-ray characterization during interrupted loading. A Linkam TS1500V vacuum heater was commissioned for thermally driven studies, and temperature calibration experiments were performed to establish specimen-relevant thermal profiles. In parallel, a customized split-tube furnace for high-temperature mechanical testing entered commissioning, and initial work began on robotic sample handling to reduce worker dose and improve operational efficiency. Data workflow and beamline operations continued to mature. Together, these developments demonstrate that the AML is becoming a unique national resource for safe, efficient, and scientifically advanced characterization of activated materials at the APS.

Zhang, Xuan↗
NASA NTRS1973

A survey of the selenochemistry of major, minor and trace elements.

Average data for igneous and/or metaigneous rocks and soils from seven lunar sites are presented. There are compositional similarities between Apollo 11 and Luna 16 eastern maria, Ap 12 and 15 western maria, and between Ap 16 and L 20 highlands. Subtle differences do exist between the paired mare sites and the two highland sites and striking differences between the eastern and western maria. Chondritic normalized REE (rare earth element) patterns for igneous rocks and soils from all sites range from 7-350 generally with negative Eu anomalies. Anorthositic gabbroes to anorthosites, presumably highland material, exhibit a positive Eu anomaly. The REE patterns or Sr isotopic ratios suggest two lava flows each for the L 16 and Ap 14 sites, at least four lava flows for the Ap 11 and 12 site and about six for the Ap 15 site.

Schmitt, R. A.↗
NASA NTRS1972

Apollo 15 mission report. Supplement 3: Ascent propulsion system final flight evaluation

Results from the postflight analysis of the ascent propulsion system (APS) performance during the Apollo 15 mission are presented. The duty cycle for the LM-10 APS consisted of two firings, and ascent stage liftoff from the lunar surface and the terminal phase ignition (TPI) burn. An evaluation was made of APS performance for the first firing and found to be satisfactory. No propulsion data was received from the second APS burn; however, all indications were that the burn was nominal. All performance parameters were well within their LM-10 3-sigma limits. Calculated throat erosion at engine cutoff for the LM-10 APS was approximately 3 percent greater than predicted.

Griffin, W. G.↗
NASA NTRS1973

Ultraviolet photometry from the Orbiting Astronomical Observatory. VIII

A comprehensive ultraviolet photometric survey of the blue Ap stars was conducted in order to determine whether the close similarity, deduced from ground observations, between the blue Ap stars and normal B stars with similar UBV colors is maintained at wavelengths shortward of 3000 A. Data are presented for 24 Ap stars and 31 normal comparison standard dwarfs and giants observed by the Wisconsin Experiment Package on OAO 2. Both normal and peculiar stars were chosen, with a few exceptions, for their minimal interstellar reddening and for the absence of known bright companions. The similarity between blue Ap stars and normal B stars of similar UBV colors is not maintained in the ultraviolet. The blue Ap stars emit less ultraviolet flux than normal stars of like UBV colors. They are underluminous and cool in effective temperature for their colors.

Leckrone, D. S.↗
NASA NTRS1992

Lessons learned from the Autonomous Power System

The Autonomous Power System (APS) project at the NASA Lewis Research Center is designed to demonstrate the applications of integrated intelligent diagnosis, control and scheduling techniques to space power distribution systems. The project consists of three elements: the Autonomous Power Expert System (APEX) for Fault Diagnosis, Isolation, and Recovery (FDIR); the Autonomous Intelligent Power Scheduler (AIPS) to efficiently assign activities start times and resources; and power hardware (Brassboard) to emulate a space-based power system. The APS project had been through one design iteration. Each of the three elements of the APS project has been designed, tested, and integrated into a complete working system. After these three portions were completed, an evaluation period was initiated. Each piece of the system was critiqued based on individual performance as well as the ability to interact with the other portions of the APS project. These critiques were then used to determine guidelines for new and improved components of the APS system.

Ringer, Mark J.↗
NASA NTRS1991

Motion sickness elicited by passive rotation in squirrel monkeys

Previous studies on the role of the area postrema (AP) in vomiting induced in the cat by motion and drugs have shown that the AP is not essential for motion-induced vomiting, but is necessary for vomiting to apomorphine and xylazine. To confirm these findings and to determine the role of the AP in the formation of Conditioned Taste Aversion (CTA), the AP was ablated bilaterally in 10 adult female cats. With one exception, the ablated cats continued to vomit to the same 1n0tion that elicited emesis before the ablation. Doses of xylazine and apomorphine that elicit emesis in intact cats, failed to induce emesis in the ablated cats. Histological examination indicated that 8 cats had complete lesions and 2 had partial lesions. Investigations of effects of AP ablations on CTA revealed that cats with complete lesions did not form CTA to flavored milk paired with xylazine injections. However, cats with partial lesion developed xylazine-induced CTA. Seven of the 8 completely lesioned cats developed motion-induced CTA, even though emesis was not consistently elicited by motion. These results suggest that there are multiple routes for inducing CTA and the emetic reflex, that CTA can form without eliciting emesis, and that CTA may be a sensitive measure of sub-emetic motion sickness.

M Corcoran↗
NASA NTRS1992

STARBASE: Database software for the automated plate scanner

The Automated Plate Scanner (APS) of the University of Minnesota, a unique high speed 'flying spot' laser scanner, is currently being used to scan and digitize the 936 O and E plate pairs of the first epoch Palomar Sky Survey. The resultant database will be used to produce a catalog of approximately a billion stars and several million galaxies. The authors describe the ongoing development of a dedicated APS database management system which will be made available to the astronomical community via INTERNET. A specialized DBMS called STARBASE has been written to provide fast access to the hundreds of millions of images collected by the APS. This system provides an initial reduction mode for parameterizing APS images and classifying image types using a novel set of neural network image classifiers. A second analysis mode, which will be that commonly used by the general user, provides for searches of the database which may be constrained by any combination of physical and positional parameters. Through the use of pointer hash trees, the system has been optimized for extremely fast positional searches using either right ascension and declination on the sky or linear X and Y positions on the POSS field. In addition to fast data retrieval, the system provides a graphical interface for displaying scatter plots or histograms of the collected data. In addition, a specialized image display system is being developed to allow the user to view densitometric data for all objects classified as extended by the neural network system. Finally, STARBASE has a flexible programmable interface which allows other programs to access information in the database. This allows users to write applications suited to their particular needs to process APS data.

Odewahn, S. C.↗
NASA NTRS1980

Effect of Ablation of Area Postrema on Frequency and Latency of Motion Sickness-Induced Emesis in the Squirrel Monkey

Twelve young adult squirrel monkeys of the Bolivian subspecies were subjected to continuous counter-clockwise horizontal rotary motion at 25 rpm, together with a sinusoidal vertical excursion of 6 in. every 2 sec (0.5 Hz). Each animal was exposed to this motion regimen for a period of 60 min once each week for three consecutive weeks. Following the third weekly motion test bilateral ablation of the Area Postrema (AP) was performed in eight of the animals by thermal cautery. Two control animals were sham-operated after the third motion test while two additional controls were given the motion tests as noted above but were not operated. The four controls were considered as a single group for statistical analyses of results of the motion tests. After a recovery period of 30 to 40 days, and at a comparable interval in the non-operated controls, each animal was again tested for motion sensitivity for three consecutive weeks. The brains of all of the animals were then fixed by left ventriculal cardiac perfusion with Bouin's fluid and processed for histological evaluation of the bilateral AP ablation in comparison with the control brains. Five of the AP-ablated animals postoperatively were completely refractory to the motion stimuli, two exhibited a decreased number of emetic responses, and one exhibited the same number of responses before and after the AP lesions. The controls exhibited no significant difference in emetic sensitivity on the second series of three weekly tests than on the first series. The results of this investigation appear to be in agreement with the observations of Wang and Chinn in the dog indicating that the integrity of the AP (CTZ) is essential to the emetic response to motion.

Brizzee, K. R.↗
NASA NTRS1997

Alkaline phosphatase in osteoblasts is down-regulated by pulsatile fluid flow

It is our hypothesis that interstitial fluid flow plays a role in the bone remodeling response to mechanical loading. The fluid flow-induced expression of three proteins (collagen, osteopontin, and alkaline phosphatase) involved in bone remodeling was investigated. Rat calvarial osteoblasts subjected to pulsatile fluid flow at an average shear stress of 5 dyne/cm2 showed decreased alkaline phosphatase (AP) mRNA expression after only 1 hour of flow. After 3 hours of flow, AP mRNA levels had decreased to 30% of stationary control levels and remained at this level for an additional 5 hours of flow. Steady flow (4 dyne/cm2 fluid shear stress), in contrast, resulted in a delayed and less dramatic decrease in AP mRNA expression to 63% of control levels after 8 hours of flow. The reduced AP mRNA expression under pulsatile flow conditions was followed by reduced AP enzyme activity after 24 hours. No changes in collagen or osteopontin mRNA expression were detected over 8 hours of pulsatile flow. This is the first time fluid flow has been shown to affect gene expression in osteoblasts.

Non-NASA Center↗
NASA NTRS2011

Performance of Airborne Precision Spacing Under Realistic Wind Conditions and Limited Surveillance Range

With the expected worldwide increase of air traffic during the coming decade, both the Federal Aviation Administration's (FAA's) Next Generation Air Transportation System (NextGen), as well as Eurocontrol's Single European Sky ATM Research (SESAR) program have, as part of their plans, air traffic management (ATM) solutions that can increase performance without requiring time-consuming and expensive infrastructure changes. One such solution involves the ability of both controllers and flight crews to deliver aircraft to the runway with greater accuracy than they can today. Previous research has shown that time-based spacing techniques, wherein the controller assigns a time spacing to each pair of arriving aircraft, can achieve this goal by providing greater runway delivery accuracy and producing a concomitant increase in system-wide performance. The research described herein focuses on one specific application of time-based spacing, called Airborne Precision Spacing (APS), which has evolved over the past ten years. This research furthers APS understanding by studying its performance with realistic wind conditions obtained from atmospheric sounding data and with realistic wind forecasts obtained from the Rapid Update Cycle (RUC) short-range weather forecast. In addition, this study investigates APS performance with limited surveillance range, as provided by the Automatic Dependent Surveillance-Broadcast (ADS-B) system, and with an algorithm designed to improve APS performance when ADS-B surveillance data is unavailable. The results presented herein quantify the runway threshold delivery accuracy of APS under these conditions, and also quantify resulting workload metrics such as the number of speed changes required to maintain spacing.

Wieland, Frederick↗
NASA NTRS2004

CMOS VLSI Active-Pixel Sensor for Tracking

An architecture for a proposed active-pixel sensor (APS) and a design to implement the architecture in a complementary metal oxide semiconductor (CMOS) very-large-scale integrated (VLSI) circuit provide for some advanced features that are expected to be especially desirable for tracking pointlike features of stars. The architecture would also make this APS suitable for robotic- vision and general pointing and tracking applications. CMOS imagers in general are well suited for pointing and tracking because they can be configured for random access to selected pixels and to provide readout from windows of interest within their fields of view. However, until now, the architectures of CMOS imagers have not supported multiwindow operation or low-noise data collection. Moreover, smearing and motion artifacts in collected images have made prior CMOS imagers unsuitable for tracking applications. The proposed CMOS imager (see figure) would include an array of 1,024 by 1,024 pixels containing high-performance photodiode-based APS circuitry. The pixel pitch would be 9 m. The operations of the pixel circuits would be sequenced and otherwise controlled by an on-chip timing and control block, which would enable the collection of image data, during a single frame period, from either the full frame (that is, all 1,024 ~ 1,024 pixels) or from within as many as 8 different arbitrarily placed windows as large as 8 by 8 pixels each. A typical prior CMOS APS operates in a row-at-a-time ( grolling-shutter h) readout mode, which gives rise to exposure skew. In contrast, the proposed APS would operate in a sample-first/readlater mode, suppressing rolling-shutter effects. In this mode, the analog readout signals from the pixels corresponding to the windows of the interest (which windows, in the star-tracking application, would presumably contain guide stars) would be sampled rapidly by routing them through a programmable diagonal switch array to an on-chip parallel analog memory array. The diagonal-switch and memory addresses would be generated by the on-chip controller. The memory array would be large enough to hold differential signals acquired from all 8 windows during a frame period. Following the rapid sampling from all the windows, the contents of the memory array would be read out sequentially by use of a capacitive transimpedance amplifier (CTIA) at a maximum data rate of 10 MHz. This data rate is compatible with an update rate of almost 10 Hz, even in full-frame operation

Pain, Bedabrata↗
NASA NTRS2011

Performance of Airborne Precision Spacing Under Realistic Wind Conditions

With the expected worldwide increase of air traffic during the coming decade, both the Federal Aviation Administration s (FAA s) Next Generation Air Transportation System (NextGen), as well as Eurocontrol s Single European Sky ATM Research (SESAR) program have, as part of their plans, air traffic management solutions that can increase performance without requiring time-consuming and expensive infrastructure changes. One such solution involves the ability of both controllers and flight crews to deliver aircraft to the runway with greater accuracy than is possible today. Previous research has shown that time-based spacing techniques, wherein the controller assigns a time spacing to each pair of arriving aircraft, is one way to achieve this goal by providing greater runway delivery accuracy that produces a concomitant increase in system-wide performance. The research described herein focuses on a specific application of time-based spacing, called Airborne Precision Spacing (APS), which has evolved over the past ten years. This research furthers APS understanding by studying its performance with realistic wind conditions obtained from atmospheric sounding data and with realistic wind forecasts obtained from the Rapid Update Cycle (RUC) short-range weather forecast. In addition, this study investigates APS performance with limited surveillance range, as provided by the Automatic Dependent Surveillance-Broadcast (ADS-B) system, and with an algorithm designed to improve APS performance when an ADS-B signal is unavailable. The results presented herein quantify the runway threshold delivery accuracy of APS un-der these conditions, and also quantify resulting workload metrics such as the number of speed changes required to maintain spacing.

Wieland, Frederick↗
NASA NTRS2014

Predicting Solar Cycle 24 Using a Geomagnetic Precursor Pair

We describe using Ap and F(10.7) as a geomagnetic-precursor pair to predict the amplitude of Solar Cycle 24. The precursor is created by using F(10.7) to remove the direct solar-activity component of Ap. Four peaks are seen in the precursor function during the decline of Solar Cycle 23. A recurrence index that is generated by a local correlation of Ap is then used to determine which peak is the correct precursor. The earliest peak is the most prominent but coincides with high levels of non-recurrent solar activity associated with the intense solar activity of October and November 2003. The second and third peaks coincide with some recurrent activity on the Sun and show that a weak cycle precursor closely following a period of strong solar activity may be difficult to resolve. A fourth peak, which appears in early 2008 and has recurrent activity similar to precursors of earlier solar cycles, appears to be the "true" precursor peak for Solar Cycle 24 and predicts the smallest amplitude for Solar Cycle 24. To determine the timing of peak activity it is noted that the average time between the precursor peak and the following maximum is approximately equal to 6.4 years. Hence, Solar Cycle 24 would peak during 2014. Several effects contribute to the smaller prediction when compared with other geomagnetic-precursor predictions. During Solar Cycle 23 the correlation between sunspot number and F(10.7) shows that F(10.7) is higher than the equivalent sunspot number over most of the cycle, implying that the sunspot number underestimates the solar-activity component described by F(10.7). During 2003 the correlation between aa and Ap shows that aa is 10 % higher than the value predicted from Ap, leading to an overestimate of the aa precursor for that year. However, the most important difference is the lack of recurrent activity in the first three peaks and the presence of significant recurrent activity in the fourth. While the prediction is for an amplitude of Solar Cycle 24 of 65 +/- 20 in smoothed sunspot number, a below-average amplitude for Solar Cycle 24, with maximum at 2014.5+/-0.5, we conclude that Solar Cycle 24 will be no stronger than average and could be much weaker than average.

predictions↗
NASA NTRS2016

The Alignment and Phasing System for the Thirty Meter Telescope: Risk Mitigation and Status Update

Alignment and Phasing System (APS) is responsible for the optical alignment via starlight of the approximately 12,000 degrees of freedom of the primary, secondary and tertiary mirrors of Thirty Meter Telescope (TMT). APS is based on the successful Phasing Camera System (PCS) used to align the Keck Telescopes. Since the successful APS conceptual design in 2007, work has concentrated on risk mitigation, use case generation, and alignment algorithm development and improvement. Much of the risk mitigation effort has centered around development and testing of prototype APS software which will replace the current PCS software used at Keck. We present an updated APS design, example use cases and discuss, in detail, the risk mitigation efforts.

Optical Alignment↗
NASA NTRS2018

Northern Hemisphere Surface Freeze-Thaw Product from Aquarius L-Band Radiometers

In the Northern Hemisphere, seasonal changes in surface freeze–thaw (FT) cycles are an important component of surface energy, hydrological and eco-biogeochemical processes that must be accurately monitored. This paper presents the weekly polar-gridded Aquarius passive L-band surface freeze–thaw product (FT-AP) distributed on the Equal-Area Scalable Earth Grid version 2.0, above the parallel 50 N, with a spatial resolution of 36 km36 km. The FT-AP classification algorithm is based on a seasonal threshold approach using the normalized polarization ratio, references for frozen and thawed conditions and optimized thresholds. To evaluate the uncertainties of the product, we compared it with another satellite FT product also derived from passive microwave observations but at higher frequency: the resampled 37 GHz FT Earth Science Data Record (FTESDR). The assessment was carried out during the overlapping period between 2011 and 2014. Results show that 77.1% of their common grid cells have an agreement better than 80 %. Their differences vary with land cover type (tundra, forest and open land) and freezing and thawing periods. The best agreement is obtained during the thawing transition and over forest areas, with differences between product mean freeze or thaw onsets of under 0.4 weeks. Over tundra, FT-AP tends to detect freeze onset 2–5 weeks earlier than FT-ESDR, likely due to FT sensitivity to the different frequencies used. Analysis with mean surface air temperature time series from six in situ meteorological stations shows that the main discrepancies between FT-AP and FT-ESDR are related to false frozen retrievals in summer for some regions with FT-AP. The Aquarius product is distributed by the U.S. National Snow and Ice Data Center (NSIDC) at https://nsidc.org/data/aq3_ft/versions/5 with the DOI https://doi.org/10.5067/OV4R18NL3BQR.

Prince, Michael↗
NASA NTRSDate not supplied

Investigating the Adhesion Force of Lunar Regolith Particulates on Air Plasma Sprayed Alumina Coatings

Ceramic materials, often used to protect components due to their high strength, and wear resistance, have added benefits of being lightweight and providing multifunctional properties. They are, therefore, significant to provide durability and support during long-duration missions to the moon’s surface for rovers, landers, robotic systems, habitats, and many other components. Materials such as aluminum oxide with high mechanical strength and hardness can help to improve the durability of structures used in space exploration. Devices used for space exploration require the use of materials with the ability to withstand exposure to extreme environments. Lunar regolith is a constituent with the ability to adhere electrostatically and damage the components used to perform these missions due to adhesion of lunar dust projectiles that can cause delamination on surfaces, which may not be physically visible. The particulates of lunar dust are classified as corrosive material, leading to the degradation of structures. Aluminum oxide presents excellent resistance to different types of wear due to its high strength and hardness. Air plasma sprayed (APS) aluminum oxide coatings have demonstrated the potential to protect the surface to which they are applied. However, the parameters of roughness and porosity of the coatings need to be considered to establish if they can protect the components from extreme environments. Considering the electrostatic forces that the components are exposed to, the adhesion between the lunar regolith and the surface of the components needs to be investigated. In this work, the adhesion forces of lunar dust simulants with an average size of 30 𝜇m are investigated considering the roughness of the surface of the APS aluminum oxide. The centrifugal technique utilized here offers the advantage of establishing the adhesion force between particles with different shapes on smooth or rough surfaces. The simulants were deposited on the surface of APS aluminum oxide using an aerosolization technique to achieve a monolayer coating in three different locations across the specimen to determine the increments in adhesion force at the centrifuge. The roughness of the APS aluminum oxide was determined to be 2.257 𝜇m. The specimen was tested under an incremental centrifugal speed from 100 rpm to 3000 rpm for 20 seconds. Low magnification microscopy images were collected to cover a larger surface area of the test coating. The adhesion force was measured considering the distance from the centrifugal axis and the rotational speed. Due to the coating roughness, and the distance from the centrifugal axis, the results demonstrated a larger adhesion force in locations closer to the centrifugal axis. Smaller particles were entrapped within the roughness of the coating, and a stronger adhesion force was measured. In order to continue designing wear-resistant coating for structural protection in space missions, press-on experiments using a centrifuge will be performed. Future experiments will allow us to determine the design parameters for APS aluminum oxide coating to protect the structures from harsh space environments.

Perla Latorre-Suarez↗
NASA NTRSDate not supplied

Measuring the Wear and Abrasive Resistance of Air Plasma Sprayed Aluminum Oxide for Lunar Exploration

Lunar regolith, especially finer dust particles traveling at high velocities, can cause significant wear and abrasive damage to structural components that ensure a prolongated presence on the surface of the Moon. With the absence of an atmosphere and lower gravity than on Earth, regolith particles maintain high velocities at large distances from where they were generated, for example next to lunar landers. Wear-resistant ceramic and ceramic composite materials can improve the durability of spacecraft components during long missions on the Moon’s surface. Aluminum oxide coatings are lightweight, have multifunctional properties, and have high strength including high hardness and wear resistance. These properties can help improve the durability of structures used in space exploration. Air plasma sprayed (APS) aluminum oxide coatings have demonstrated the potential to protect critical structures. This study investigated the abrasive wear resistance of APS aluminum oxide coatings via Taber abrasion experiments. Taber abrasion offers the advantage of quantifying the abrasive wear behavior of particles with different shapes on a surface. In this work, an abrasive wheel made of silicon carbide was utilized to evaluate wear properties of specimens progressively over 5000 cycles. This experiment focused on testing two series of specimens to determine whether a bond coat composed of nickel, chromium, aluminum, and yttrium (NiCrAlY) improved the protective behavior of the APS aluminum oxide coating. The specimens varied in topcoat thickness and were made with and without an approximately 100 µm bond coat layer. The mass of the specimens was measured at 400 cycles, 800 cycles, 3800 cycles, and 5000 cycles. Increasing thickness was found to result in higher wear for samples with and without a bond coat. Increased mass loss in samples with a bond coat was observed indicating a need for further studies on the overall impact of the use of a bond coat on the protective behavior of the coatings. To continue designing wear resistant coatings for structural protection in space missions, the multifunctional properties of the APS aluminum oxide coating will be studied. Future experiments will determine whether the APS aluminum oxide coating can protect the structures from other aspects of the harsh space environment, such as extreme temperature variations and ionizing radiation.

aluminum oxide↗