Search NASA⌕ Search

SEARCH · Search NASA

Results for “ABRASIVE”

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.

At least 1,063 records · Page 59
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

High gain durable anti-reflective coating

Disclosed herein are polysilsesquioxane-based anti-reflective coating (ARC) compositions, methods of preparation, and methods of deposition on a substrate. In one embodiment, the polysilsesquioxane of this disclosure is prepared in a two-step process of acid catalyzed hydrolysis of organoalkoxysilane followed by addition of tetralkoxysilane that generates silicone polymers with >40 mol % silanol based on Si-NMR. These high silanol siloxane polymers are stable and have a long shelf-life in polar organic solvents at room temperature. Also disclosed are low refractive index ARC made from these compositions with and without additives such as porogens, templates, thermal radical initiator, photo radical initiators, crosslinkers, Si--OH condensation catalyst and nano-fillers. Also disclosed are methods and apparatus for applying coatings to flat substrates including substrate pre-treatment processes, coating processes and coating curing processes including skin-curing using hot-air knives. Also disclosed are coating compositions and formulations for highly tunable, durable, highly abrasion-resistant functionalized anti-reflective coatings.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Anti-reflective and anti-soiling coatings with self-cleaning properties

Disclosed herein is a coated glass element including a glass component and a coating adhered to the glass component through siloxane linkages, the coating having at least one of an anti-reflective property, a high abrasion resistance property and a hydrophobic property, wherein the coating comprises a dried gel formed from at least one hydrolyzed alkoxysilane-based sol and at least one hydrolyzed organosilane-based sol.

36 MATERIALS SCIENCE↗
DOE OSTI2017

High gain durable anti-reflective coating

Disclosed herein are polysilsesquioxane-based anti-reflective coating (ARC) compositions, methods of preparation, and methods of deposition on a substrate. In one embodiment, the polysilsesquioxane of this disclosure is prepared in a two-step process of acid catalyzed hydrolysis of organoalkoxysilane followed by addition of tetralkoxysilane that generates silicone polymers with >40 mol % silanol based on Si-NMR. These high silanol siloxane polymers are stable and have a long shelf-life in polar organic solvents at room temperature. Also disclosed are low refractive index ARC made from these compositions with and without additives such as porogens, templates, thermal radical initiator, photo radical initiators, crosslinkers, Si--OH condensation catalyst and nano-fillers. Also disclosed are methods and apparatus for applying coatings to flat substrates including substrate pre-treatment processes, coating processes and coating curing processes including skin-curing using hot-air knives. Also disclosed are coating compositions and formulations for highly tunable, durable, highly abrasion-resistant functionalized anti-reflective coatings.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Window to the Hot Cell: The Challenges of Repairing a Specialized Nuclear Containment

Here, at the Idaho National Laboratory (INL) nuclear R&D site we come across a myriad of challenges and health hazards. Recently, a first time activity for the INL was to replace a hot cell window put in place circa 1977. This job evolution was complex in nature and involved several health and safety hazards. A hot cell is a containment designed to protect workers from radioactivity yet continue to allow work with remote handled tools and windows for visibility. The hot cell window weighed approximately 14,000 lbs. and was held in place by 1.6 cubic yards of high density grout. Removal of the window required abrasive grout removal techniques, radiological control efforts, specialized ventilation, and personal protective equipment utilization. In order to contain the large amounts of dust from the removal of concrete and potential contamination exposure a special containment tent and ventilation system was designed to protect workers in the surrounding areas from dust and debris. Once the window was removed it had to be further taken apart for shipment. While performing this activity, several lead sheets and lead wool was required to be removed. Overall it took 38 days to accomplish this task and had several organizations involved. There were no injuries or unexpected conditions that occurred during this job task. This was the first time this activity was performed at the INL and was completed in a successful manner. Further windows are set to be replaced in the near future.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2018

Identification of biomass fractions responsible for wear on biomass processing equipment

Abstract: There is a current problem in the DOE supported Integrated Bio refineries where metal parts, including grinder blades and pneumatic ducting, are wearing out too early in the lifetime of the equipment. Repairing and replacing the equipment leads to unexpected equipment costs and the complete shutdown of the affected production lines.. It is believed that the ash content of the biomass is the likely cause of the wear on the metals. To address this ongoing problem, INL staff are analyzing the wear of metals caused by interactions with biomass . A sandblaster was modified to shoot ground biomass at metal coupons to simulate the wear that is occurring in the bio refineries. This system was able to test several variables including which biomass causes erosive and abrasive wear, impingement angle, particle densities of the biomass, and how the quantity of mass impacts the wear of the metals. Coupon mass loss after blasting was used to evaluate the wear caused by different biomass fractions. It was determined that the bark fraction of biomass caused the most wear and the whitewood fraction caused the least wear. Coupon mass loss in logging residues was found to be positively correlated with ash content, indicating that the ash content in the biomass is responsible for wear. It was also found that hand separated forest residues, sodium, aluminum and iron were positively correlated with wear, while silicon showed no correlation with wear.

09 BIOMASS FUELS↗
DOE OSTI2019

Effect of Deposition Temperature on the Tribology of MOCVD Zinc Oxide Thin Films Tested under Dry Contact

Zinc oxide has justifiably been attracting attention in several fields, and the relatively new field of tribology is not left out. Aside from its already extensively researched and documented applications in materials science, semiconductor and electronics industry, zinc oxide nanoparticles and thin films appear to be gaining fast grounds as tribological materials, thereby justifying a zealous approach in further exploring their inherent properties in this area. In this work, zinc oxide thin films were deposited by MOCVD (metal-organic chemical vapour deposition) on soda lime glass andAISI304L stainless steel plates at temperatures of 300°C, 330°C, 360°C, 390°C and 420°C respectively, using anhydrous zinc acetate as the precursor. The carrier gas was air with a flow rate of 2.5 dm 3 min -1 at atmospheric pressure, and deposition time of 2 hours each. The thickness and tribological properties of the thin films produced were thereafter investigated. The thickness was measured by RBS (Rutherford backscattering spectroscopy) using a 1.7 MeV Tandem Accelerator, and the friction and wear properties were tested with a HFRR (high frequency reciprocating rig) under dry contact conditions, Olympus BH-2 Optical Microscope, and ADE Phase Shift MicroXam Optical Surface Profiler. The thickness was found to decrease with increasing deposition temperature, although for the 300°C deposition temperature there appeared to be a bloated thickness, which is attributable to such factors as incomplete precursor decomposition, turbulence in precursor flow, and energy straggling during RBS measurement. The friction tests highlighted coefficients of friction which were relatively low at the onset of the tests, but thereafter rapidly increased, owing possibly to temperature rise, attendant rapid oxidation and aided abrasion by worn debris. The average coefficient of friction of each test was computed, and the outcome (0.33 – 0.43) for all of them was a material still good enough for use in reducing friction at nanolevel, even with worn out matter and increased working temperature, with no noticeable trend regarding their varied deposition temperatures. Microscope and profilometer profiles vividly showed wear scars with material removal and material transfer. The average wear scar diameters as well as the wear volumes were compiled for both the test balls and the thin films. The result showed a largely correlated trend in the wear scar diameters and the wear volumes, and the thin film deposited at 330°C was the coating with the least wear scars, material removal cum transfer on the test ball and sample. This result is attributed to the enhanced thickness of the sample over the others, apart from sample X1 earlier reported to have a problem in its thickness. As a result, this temperature is therefore recommended as the optimum deposition temperature for the best tribologically applicable zinc oxide thin films, using zinc acetate precursor by MOCVD.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Silica Development For Sidewall Compounds

Tire tread is the single largest contributor to tire rolling resistance. Because of this, most developments to improve tire rolling resistance have focused on the incorporation of precipitated silicas into the tread compounds. However, still approximately 50% of the tire rolling resistance is attributed to the energy dissipation of non-tread components. The next largest contributor to rolling resistance after the tread is the sidewall, which contributes to about 20% of the tire rolling resistance. For this reason, the sidewall is an excellent candidate to achieve additional fuel efficiency improvements by taking advantage of the known reduction in hysteresis obtained when using silica in place of carbon black. The sidewall is a compound rich in natural rubber which needs to have good weathering, tear, abrasion, fatigue, and ozone-induced cracking resistance. Hysteresis improvements cannot be achieved at the expense of resistance to these degradative forces. Initial studies showed that treated silica can deliver reduced hysteresis, but the impact on other key performance properties required further investigation. Results are presented here showing the effect of partially replacing carbon black with treated silica in a sidewall model formulation. Emphasis is placed in reducing hysteresis while maintaining other performance properties.

Dos Santos Freire, Lucas↗
DOE OSTI2019

Air maintenance tire

A self-inflating tire assembly includes an air tube mounted within a tire sidewall or chafer groove. The air tube is in contacting engagement with opposite angled groove surfaces surrounding the air tube. A segment of the air tube is flattened from an expanded diameter to a flat diameter by bending and compression of the groove in a rolling tire footprint to force air evacuated from the flattened segment along a tube air passageway. A coverstrip overlays and seals the groove and provides an abrasion resistant surface on the exterior of the tire. The coverstrip is made from a vulcanizable rubber composition comprising from 50 to 80 phr of a polybutadiene, from 50 to 20 phr of natural rubber, and from 0.1 to 5 phr of a vulcanization modifier.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

High Temperature Erosion In Particle Based CSP Systems

Particle based concentrated solar power plants are increasingly being considered as an alternative to molten salts. Although these particle based systems provide the inherent safety and enhanced lifetime from reduced corrosion compared to molten salt systems, they bring in complexities associated with surface erosion from falling particle impact and sliding motion along the surfaces. Past research on particle related erosion has been limited to high velocity applications and doesn’t necessarily coincide with the operating conditions in CSP systems. In our work, we evaluate characterize the rate of erosion for particles and containment materials at 800ºC. Three different types of erosion resulting from a) impact of solid particles on receiver, particle storage, and heat exchanger walls; b) abrasion erosion from particle sliding motion along walls; and c) attrition erosion as the particles breakdown from particle-to-particle contact and particle-to-wall interactions are evaluated and compared across a varied spectrum of particle and containment material spectrum. From the results, It is noted that temperature plays a key role in the rate of erosion experienced by any material. With the increase in temperature, materials become more ductile and are more readily sheared away from particle impinging or sliding motion. Furthermore, the particles themselves have higher susceptibility to breakdown which also lowers particle thermal absorptance and thus efficiency as heat transfer fluid.

14 SOLAR ENERGY↗
DOE OSTI2021

A Custom High-Throughput Optical Mapping Instrument (OMI) for Accelerated Stress Testing of PV Module Materials

The performance and integrity of photovoltaic (PV) modules and materials may be assessed through optical characterizations. We have developed a custom Optical Mapping Instrument (OMI) to improve measurement throughput time, facilitate automated measurements, and obtain spatial information relative to commercial benchtop spectrophotometer instruments. Both the key components and the methods used to improve the measurements are described. The measurement precision for the OMI is benchmarked for hemispherical transmittance relative to a previous round-robin study for commercial spectrophotometers. Example mapping measurements and their implications are given for specimens from other studies, including: (1) the depletion of the UV absorber is revealed for specimens beyond a certain size after standardized artificial ultraviolet (UV) weathering, (2) an optical degradation by internal haze formation is confirmed following Damp Heat (85°C/85% relative humidity) testing, (3) the better uniformity of the wear pattern for falling sand abrasion is used to select the DIN 52348 fixture over the ASTM D968 fixture, and (4) the local (millimeter-scale) heterogeneity of surface contamination in the soiling-prone location of Dubai relative to Kuwait. The results of the UV study have already been used to improve the standardized weathering of encapsulants. The example for Damp Heat testing is given to increase awareness of a degradation believed to be ubiquitously occurring in safety and design-type qualification testing of PV modules.

41 EE - Solar Energy Technologies Office (EE-4S)↗
DOE OSTI2021

Alternative low cost electrodes for hybrid flow batteries

An electrode for use in an all-iron redox flow battery is provided. In one example, the electrode may include a plastic mesh; and a coating on the plastic mesh. The coating may be a hydrophilic coating or a conductive coating and the electrode may have an electrode reaction potential is less than 0.8V. Further, a method of manufacturing a coated plastic mesh electrode for use in an all-iron redox flow battery is provided. In one example method, the steps include fabricating a plastic mesh, treating the plastic mesh by applying a solvent treatment or a plasma treatment or a mechanical abrasion treatment; coating the plastic mesh with a material selected from: carbon inks, metal oxides, and hydrophilic polymers.

Evans, Craig E.↗
DOE OSTI2021

ROP model for PDC bits in Geothermal drilling

Geothermal energy is a renewable source of energy, where heat extraction is preferentially balanced with the reservoir's natural heat recharge rate. The objective of this paper is to present and validate a novel rate of penetration (ROP) model for drilling hard and abrasive formations including granite formations for polycrystalline diamond compact (PDC) bits. The ROP model was developed based on a derived relationship of a threshold weight on cutter (WOC) and its corresponding depth of cut (DOC) for a single cutter. Laboratory data was used to scale the derived single cutter relationship to a full-hole ROP model for PDC bits. The ROP model includes a non-linear correlation for Phase I (inefficient drilling due to low WOB values) and a linear Phase II (efficient drilling) ROP response to WOB. The ROP model was verified using measured drilling parameter data from Utah FORGE well# 58-32 and data from Chocolate Mountains well # 17-8 in Southern California. When compared to oil and gas well drilling, geothermal drilling in granitic formations can be more difficult and complicated due to rock hardness and high temperatures. PDC bits can increase ROP and optimize drilling for these types of hard formations. This paper provides novel insight into the ROP response of PDC bits to drilling operational parameters.

15 GEOTHERMAL ENERGY↗
DOE OSTI2022

Fluid-powered linear motor with rotary pistons and motion rectifier and synthetic diamond bearing assemblies

A fluid-powered linear motor with rotary pistons is disclosed. An application is for a downhole motor but it could be used in other applications. Rotational pistons provide increased torque generation as the torque generated is proportional to motor length. Since downhole drills are long (generally up to a maximum length of 30 ft.), a high-torque motor can be produced using this method. A pressurized fluid is used to drive the piston assemblies to produce bit shaft power. This concept employs rotary pistons and a mechanical rectifier to convert the rotational reciprocation produced by a reciprocating rotational piston into continuous rotary motion. Integration of synthetic diamond bearing assemblies into the motor allows for reduced friction and abrasive drilling fluid compatibility.

Raymond, David W.↗
DOE OSTI2023

GRAPHITE–MOLTEN SALT CONSIDERATIONS FOR COMPONENTS IN NUCLEAR APPLICATIONS

The new High Temperature Reactor (HTR) designs being considered for future Gen IV nuclear reactor deployment include designs utilizing molten salt as the primary coolant. These molten-salt cooled, graphite core designs pose new material compatibility challenges that are not considered within the gas-cooled HTR designs that have been previously built and operated. While the Molten Salt Reactor Experiment (MSRE) demonstrated that the molten salt can be considered chemically inert to graphite the novel physical and thermal interactions that the molten salt poses may be just as impactful as the chemical reactivity. Specifically, molten salt intrusion into the open pore structure of nuclear graphite grades can provide additional internal stresses within the microstructure exacerbating the stress buildup from irradiation induced dimensional change. Additionally, designs using a molten salt containing liquid fuel could provide “hot spots” within graphite structural components causing local thermal stresses. Abrasion and erosion concerns are magnified with molten salt due to the extremely high density of the salts (some have higher densities than the structural graphite components). Finally, the graphite-graphite and fuel pebble-graphite tribological behavior are distinctly difference within the molten salt from the inert gas environments and must be investigated. These topics and others are currently under investigation within the DOE Advanced Reactor Technologies (ART) graphite program and will be discussed in depth.

Gallego, Nidia↗
DOE OSTI2023

DuPont Nomex 410 Datasheet

Nomex 410 is a type of electrical insulation paper that can be found in a large variety of electrical applications. It exhibits a combination of good thermal stability, mechanical toughness, abrasion resistance, dielectric strength, broad chemical compatibility, and flame resistance. Nomex 410 is a high-density variety of a broader class of Nomex insulation papers, which makes it suitable for applications where high mechanical resilience is more important than impregnability or saturability.

Pingree, Richard↗
DOE OSTI2012

Surface Decontamination Using Laser Ablation Process - 12032

A new decontamination method has been investigated and used during two demonstration stages by the Clean-Up Business Unit of AREVA. This new method is based on the use of a Laser beam to remove the contaminants present on a base metal surface. In this paper will be presented the type of Laser used during those tests but also information regarding the efficiency obtained on non-contaminated (simulated contamination) and contaminated samples (from the CEA and La Hague facilities). Regarding the contaminated samples, in the first case, the contamination was a quite thick oxide layer. In the second case, most of the contamination was trapped in dust and thin grease layer. Some information such as scanning electron microscopy (SEM), X-Ray scattering spectroscopy and decontamination factors (DF) will be provided in this paper. Laser technology appears to be an interesting one for the future of the D and D applications. As shown in this paper, the results in terms of efficiency are really promising and in many cases, higher than those obtained with conventional techniques. One of the most important advantages is that all those results have been obtained with no generation of secondary wastes such as abrasives, chemicals, or disks... Moreover, as mentioned in introduction, the Laser ablation process can be defined as a 'dry' process. This technology does not produce any liquid waste (as it can be the case with chemical process or HP water process...). Finally, the addition of a vacuum system allows to trap the contamination onto filters and thus avoiding any dissemination in the room where the process takes place. The next step is going to be a commercial use in 2012 in one of the La Hague buildings. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Real-time Erosion-Corrosion Detection in Waste Transfer Pipelines using Guided Wave Ultrasonic Sensors - 18368

A Fitness-for-Service (FFS) program for the Waste Transfer System has been implemented by the United States Department of Energy Hanford Site Tank Farm to examine structural parameters of the waste transfer systems in order to develop erosion/corrosion rates for relevant system components. The FFS information is acquired from opportunistic evaluations of pipelines that have been removed from service. The objective is to deliver more realistic estimates to the remaining useful life of the components and incorporate those estimates into future design/testing plans across the DOE complex. To aid to this objective, previous efforts at Hanford included the installation of sensors on some of the POR 104 components, to provide real time pipe wall thickness measurements. Due to certain limitations, alternative approaches for remote permanently mounted pipe wall ultrasonic thickness measurement systems have been investigated by FIU. Present research work is a supportive effort by FIU-ARC for DOE and WRPS, which investigates the option for remote-permanently mount guided wave ultrasonic transducer (UT) systems for HLW pipe wall thickness measurements. Specific applications include straight sections, elbows and other fittings used in jumper pits, evaporators, and valve boxes. The proposed method will provide information that will assist engineers with understanding the failure potential of HLW transfer components due to corrosion and erosion. This information can assist in determining if and when lines need to be removed, saving time and resources on the unneeded excavation of transfer lines. This information will also assist engineers with designing new transfer systems by establishing more detailed/accurate guidelines governing the life expectancy of the transfer system and its components. In the previous work, FIU has investigated the use of various ultrasonic systems that are either commercially available or used previously at Hanford and selected the most promising systems for further evaluation. The down-selected system is the guided wave UT sensor system from Permasense which is a UK based manufacturer. It is an integrated wireless sensor network system which used a patented technology for the acoustic wave propagation and has proven applications in the oil and gas industries. Scope of the present research includes the initial verification and validation of the Permasense Guided Wave sensor system as a potential erosion/corrosion detection system for carbon steel pipelines under static conditions. In future, the real-time erosion/corrosion detection will be investigated by measuring the thinning of the pipe sections by circulating simulants and continuous monitoring. This is achieved by passing abrasive and caustic solutions through an in-house designed pipe loop system. Results obtained provide realistic wear rates on 2 inch and 3 inch carbon steel pipes with straight sections and elbows using the Permasense UT sensor system. Thus, the present research delivers solutions for sensor evaluations, conducts bench scale testing followed by data acquisition and analysis for corrosion and erosion assessment. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Advancing Core Safety of Gen IV and Gen IV + Reactors by Encompassing High-Temperature Resistant Materials - 18673

The paper focuses on the development of materials for Gen IV/IV+ reactor core. It discusses the advancement of materials studied and their application in different components of the reactor core and other auxiliary components which will help in the development of future generation reactors. The paper summarizes the material study showing the characteristic behavior of different materials (coated with FeB and FeB{sub 2}), towards irradiation at near high temperatures and high energy neutron flux condition. The project includes different materials which are coated on the boundaries with varied thickness of FeB and FeB{sub 2}. The samples included Carbon steel, Stainless steel 310, Stainless steel 316, Inconel 718. All above-mentioned samples were received by Prof. J. Szpunar, through an industry with coatings of FeB and FeB{sub 2} with varied thickness along with a bare sample of each material. The samples were irradiated at the University of Saskatchewan reactor, with fast neutron flux of 1.1x10{sup 11} n.cm{sup -2}.sec{sup -1}. I worked on all the samples but the paper particularly focuses on, two carbon steel samples results, received so far. The methodology for the project been followed for all the samples is as follow: 1. Received samples were first polished. 2. Vickers Hardness Test. 3. Mirror polished. 4. Etched with the appropriate etchant for the material. 5. Microscopic study of the etched surface. 6. SEM imaging. 7. Sent for irradiation. 8. The same set of material testing done after irradiation, with an EBSD run on the boundary and main surface. The two Carbon Steel samples (sample 21 and 19) analyzed, were irradiated for 14 hrs. Sample 21 was a bare sample and sample 19 had a coating of FeB, FeB{sub 2} with a ∼0.0010'' thickness. The methodology was followed for material testing before and after the irradiation. The advantage of FeB and FeB{sub 2} coatings are: 1. Higher hardness - 10 times (FeB-1775 and FeB{sub 2}-1450), 2. High-stress capacity, 3. Lower abrasion, 4. Low corrosion. Through the test results obtained before and after the irradiation, I was able to get a view of coating damage at the boundaries of sample 19. The bare sample don't show any difference after irradiation but the coated sample do show cracks in the FeB layer. Which can be seen in the SEM images of sample 19. The hardness results are promising, as hardness didn't change significantly. The hardness test was done on the substrate as the coating was significantly narrow to perform the test. Though the hardness test on coatings was performed by the possessor company which show hardness higher by a factor of 10 when compared to uncoated surfaces. The XRD results, reveal irradiation effect on the crystal lattice, making it deformed, which though is usual during irradiation. The overall analysis along with EBSD done on the two samples are favorable and promising. Though it still needs to be cleared out, whether the cracks on the coating were due to irradiation or due to etching after the samples were irradiated.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗