Materials Compatibility and Aging for Flux and Cleaner Combinations.
Abstract not provided.
Archuleta, Kim↗
SEARCH · Engineering Papers
Results for “materials aging”
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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KPFM-AM as a Potential Tool for Probing Aging Evidence in Materials.
Abstract not provided.
Baca, Ana B↗
Space aging of solid rocket materials
Solid rocket propellant and rocket motor components were aged in a vented container on the interior of the LDEF. The results of aging IPSM-II/PAM-DII space motor components are presented. Ballistic and mechanical properties of the space aged main propellant, igniter propellant, and ignition system were compared with similar data from preflight and ground aged samples. Mechanical properties of the composite materials and bonded joints used in the motor case, insulation, liner, nozzle, exit cone, and skirt were similarly evaluated. The space aging results are compared to data collected in a ground based vacuum aging program on similar components.
Lester, Dean M.↗
Metastable Materials Discovery in the Age of Large-Scale Computation
Computational materials discovery has been successful in predicting novel, technologically relevant materials. However, it has remained focused almost exclusively on finding ground-state structures. Now that the lower-hanging fruit has been found in many fields of application, materials exploration is moving toward metastable materials: higher energy phases that are stable at practical time scales. Because of the challenges associated with predicting which phases are realistic, this class of materials has remained relatively unexplored, despite numerous examples of metastable structures with unmatched properties (e.g., diamond). This article highlights recent advances in developing computational and theoretical methods for predicting useful and realizable metastable materials. Topics discussed cover (1) the latest strategies for identifying potential metastable phases, (2) methodologies for assessing which phases can be realized experimentally, and (3) current approaches to estimate the lifetime of metastable materials.
amorphous materials↗
Summary report on the mechanical testing performed at INL for creep rupture, fatigue, creep-fatigue, and aging of A709 base material
The report provides the status of the creep, fatigue, and creep-fatigue testing to conducted at Idaho National Laboratory to generate a data package to support Alloy 709 qualification in American Society of Mechanical Engineers, Boiler and Pressure Vessel Code, Section III, Division 5. These tests were performed on three commercial heats of plate material. The first procured heat was manufactured by G.O. Carlson with heat number 58776. Second and third heats were fabricated by ATI Specialty Rolled Products, with heat numbers 529900 and 530843, respectively. A series of creep and cyclic specimens were fabricated from these three heats, and tests were performed. This report presents a master list of all completed and ongoing creep, fatigue, and creep fatigue tests. Cyclic properties of three commercial heats are compared. Thermal aging of three commercial heats for 3000 hours were completed in FY 2025. The thermal aging campaign to age plate material from three commercial heats up to 100,000 hours is ongoing.
36 - MATERIALS SCIENCE↗
Chronic kidney disease and aging differentially diminish bone material and microarchitecture in C57Bl/6 mice
Chronic kidney disease (CKD) is a common disease of aging and increases fracture risk over advanced age alone. Aging and CKD differently impair bone turnover and mineralization. We thus hypothesize that the loss of bone quality would be greatest with the combination of advanced age and CKD. We evaluated bone from young adult (6 mo.), middle-age (18 mo.), and old (24 mo.) male C57Bl/6 mice three months following either 5/6th nephrectomy, to induce CKD, or Sham procedures. CKD exacerbated losses of cortical and trabecular microarchitecture associated with aging. Aging and CKD each resulted in thinner, more porous cortices and fewer and thinner trabeculae. Bone material quality was also reduced with CKD, and these changes to bone material were distinct from those due to age. Aging reduced whole-bone flexural strength and modulus, micrometer-scale nanoindentation modulus, and nanometer-scale tissue and collagen strain (small-angle x-ray scattering [SAXS]. By contrast, CKD reduced work to fracture and variation in bone tissue modulus and composition (Raman spectroscopy), and increased percent collagen strain. The increased collagen strain burden was associated with loss of toughness in CKD. In addition, osteocyte lacunae became smaller, sparser, and more disordered with age for Sham mice, yet these age-related changes were not clearly observed in CKD. However, for CKD, larger lacunae positively correlated with increased serum phosphate levels, suggesting that osteocytes play a role in systemic mineral homeostasis. This work demonstrates that CKD reduces bone quality, including microarchitecture and bone material properties, and that loss of bone quality with age is compounded by CKD. Finally, these findings may help reconcile why bone mass does not consistently predict fracture in the CKD population, as well as why older individuals with CKD are at high risk of fragility.
60 APPLIED LIFE SCIENCES↗
Evaluation of High Temperature Elastomers for Geothermal Wells
This report describes the extension of a performance screening study of elastomers for geothermal well applications. Elastomeric O-rings were subjected to compression while submerged in water at elevated temperatures and pressure to determine performance under more aggressive conditions. Following the experiment, the elastic moduli of the O-ring cross-sections were assessed for any changes which may affect O-ring function down-hole. All materials showed susceptibility to thermo-oxidative degradation at high temperatures and pressures. Type I FKM had the least amount of compression set of all materials tested at 150ºC while Kalrez FFKM O-rings had the least amount of edge hardening of all materials, regardless of aging temperature. Prior visual observation of materials aged in simulated environments revealed an unusual trend with EPDM and FEPM materials: the degradation and disintegration of these polymers in an oxidative thermal cycle environment, but the ability to maintain mechanical performance and shape during oxidative thermal cycling in the presence of steam. EPDM and FEPM were subjected to additional testing at SNL in order to better understand this aging anomaly. No abnormalities were observed in the chemical (oxidation rates, FTIR spectra, solvent uptake, gel content, and weight loss vs. temperature) or physical (modulus profiles) measurements that could explain the visually observed aging differences. SNL validated this observation through a secondary controlled aging test using only EPDM, where, once again, it was shown that thermo-oxidative conditions appear to cause more degradative damage (enhanced embrittlement) than did thermo-oxidative coupled with hydrolytic environments. From these data we conclude that water may favorably interfere with normal thermo-oxidative degradation processes via some type of inhibition pathway which has yet to be identified.
15 GEOTHERMAL ENERGY↗
Updated uranium reference material 231 Pa/ 235 U consensus model ages for nuclear forensics
Radiochronometry provides the model age of nuclear materials, which is useful for understanding the production history of materials found outside of regulatory control. Certified reference materials (CRMs) are important for radiochronometry to increase confidence in measurement quality; however, the absence of 231 Pa/ 235 U CRMs necessitates that nuclear forensic laboratories measure the 231 Pa/ 235 U model ages of preexisting uranium reference materials. Here, in this work, new consensus 231 Pa/ 235 U model ages are reported from three nuclear forensic laboratories for three reference materials using current analytical methods. These updated consensus values can be used for quality control of 231 Pa/ 235 U model age measurements.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
Limited life item management
Plans are available for age-sensitive hardware management. Control plan identifies shelf life or age control requirements for materials considered age sensitive, use sensitive, or time service or shelf life controlled items, and describes methods of arriving at age controls through adherence to detailed specifications.
Eaglen, R. L.↗
Activation Energies of Harvested Boston Insulated Wire and Okonite Cable Materials
As part of the Cable Aging Task within the Material Aging and Degradation (MAaD) pathway of the DOE Light Water Reactor Sustainability (LWRS) program, ORNL is collaborating with Pacific Northwest National Laboratory (PNNL), the Electric Power Research Institute (EPRI), and the US Nuclear Regulatory Commission (NCR) to study cable aging mechanisms. Understanding cable aging mechanisms in cable nuclear power plants (NPPs) with needed information as they seek plant life extensions to 80 years of operations. This report summarizes activities in the characterization of harvested electrical I&C cables related to activation energy and their role in determining the remaining margin of time cable insulation in NPPs can be used. Activation energy is the amount of energy that is required to break chemical bonds in a polymer through an endothermic reaction. For I&C cables that are utilized in NPPs, activation energy is used with a time and temperature dependent cable property like elongation at break (EAB) and/or an electrical property like voltage withstand to determine whether a cable insulation material meets the performance requirements for the environmental conditions such as temperature, radiation, and humidity for a given plant location. Considering differences in activation energies that were observed in harvested cable jackets when compared to previous measurements, an assessment of the cable insulation activation energy in harvested I&C cables was performed given that the insulation performance ultimately determines that lifetime performance for a cable. This assessment consisted of the mechanical and chemical characterization of harvested Boston Insulated Wire (BIW) and Okonite cable insulations from Zion NPP from a series of thermal accelerated aging exposures between 140°C and 160°C. Cables were obtained as part of the LWRS Zion Harvesting Project in cooperation with Energy Solutions and the NRC. Activation energies of 1.10 eV and 0.61 eV were obtained for BIW and Okonite manufactured ethylene propylene rubber (EPR) insulation with individual chlorosulfonated polyethylene (CSPE) jackets respectively. When compared to previous measurements, the activation energy of BIW agreed well, while there was a sizeable gap for previous Okonite activation energies near 0.91 eV. The lack of agreement could be attributed to differences in raw materials used in a given insulation and/or jacket, differences in the thicknesses of the EPR insulation and CSPE individual jacket or the environmental conditions that the insulation from previous measurements experienced prior to characterization especially if cables were not stored at manufacturer recommended conditions. Comparison of harvested insulation compositions from multiple NPP sites and locations in a given NPP with respect to activation energy could provide some guidance on property sensitivity and insulation variations. To address the issue of material thickness, an initial assessment of the influence of the CPSE individual jacket was also done. This was motivated by the different combinations of EPR insulation and CSPE individual jacket thicknesses that were found in harvested cables and previous measurements. Accelerated thermal aging of BIW-manufactured EPR insulation with individual CSPE jackets removed did show that the CSPE layer affected insulation degradation, further comparison of the compositional make-up of the CSPE and EPR for both BIW and Okonite insulation, along with a limited amount of additional accelerated aging, is needed to increase the level of confidence regarding the influence of the CSPE.
36 MATERIALS SCIENCE↗
Microstructure-mechanical property relationships for Al-Cu-Li-Zr alloys with minor additions of cadmium, indium or tin
Minor amounts of cadmium, indium or tin were added to a baseline alloy with the nominal composition of Al-2.4Cu-2.4Li-0.15Zr. These elements were added in an attempt to increase the age-hardening response of the material such that high strengths could be achieved through heat-treatment alone, without the need for intermediate mechanical working. The alloy variant containing indium achieved a higher peak hardness in comparison to the other alloy variations, including the baseline material, when aged at temperatures ranging from 160 C to 190 C. Tensile tests on specimens peak-aged at 160 indicated the yield strength of the indium-bearing alloy increased by approximately 15 percent compared to that of the peak-aged baseline alloy. In addition, the yield strength obtained in the indium-bearing alloy was comparable to that reported for similar baseline material subjected to a 6 percent stretch prior to peak-aging at 190 C. The higher strength levels obtaied for the indium-bearing alloy are attributed to increased number densities and homogeneity of both the T1 and theta-prime phases, as determined by TEM studies.
Blackburn, L. B.↗
Next Generation Three-Way Catalysts for Future, Highly Efficient Gasoline Engines (Final Technical Report)
Ford Motor Company, Oak Ridge National Laboratory, and the University of Michigan completed a 3.25 year project on exhaust catalysts for gasoline vehicles that exhibit higher activity at lower temperatures down to 150°C. Ford has successfully used catalysts on cars and trucks to control emissions for over forty years. Changes in gasoline engine technology have allowed the use of “high tech” three-way catalysts (TWCs) to simultaneously control HC (hydrocarbons), CO (carbon monoxide), and NOx (nitrogen oxides) at nearly 100% efficiency. Excess fueling is used upon engine start to heat the catalyst up to its full operating temperature of greater than 350°C, lowering fuel economy and creating particulate matter. It was desirable to develop new catalysts for lower operating temperatures that may occur with future, more efficient gasoline powered vehicles, while still being durable to 150,000 mi with peak temperatures of 960°C. The work included laboratory preparation, aging, and poisoning of catalyst materials, activity tests, and chemical analyses. The objective of this project was to demonstrate progress toward the USDRIVE goal of achieving durable 90% conversion (T90) of hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) at 150°C. The project partners focused on several supported metal catalyst structures to promote lower light-off temperatures, enhance metal-support interaction, and improve durability. The raw materials (oxides of aluminum, cerium, silicon, titanium, and zirconium) were not new, but were used in novel ways. Palladium (Pd) or rhodium (Rh) were supported either on layered metal oxide supports, on nanoparticles, or used in various core@shell configurations. Catalyst materials were aged hydrothermally to a simulated high mileage. The catalyst formulation with the lowest durable light-off was 0.5 wt% Rh supported on alumina with an overlayer of either Ti or Zr. The temperatures for 90% conversion were up to 128°C lower than those of a commercial Pd three-way catalyst that had > 3x metal loading of the new Rh catalyst. An additional material made of Pd supported on nanoparticles of ceria-zirconia (CZO) was also considered; the aged T90s were up to 40°C lower than the commercial catalyst, at similar metal loading. Further understanding of the catalyst architecture provided additional confidence to move forward with scale-up of 0.5 wt% Rh/Ti/Al2O3 to coated monolith laboratory cores for further evaluation. The team worked with Johnson Matthey to accomplish this, in addition to exploring manufacturability and potential costs. The overall benefit was estimated to be 10-15% lower NMOG and NOx tailpipe emissions on a cold start certification cycle.
54 ENVIRONMENTAL SCIENCES↗
Next Generation Three-Way Catalysts for Future, Highly Efficient Gasoline Engines (Final Report)
Ford Motor Company, Oak Ridge National Laboratory, and the University of Michigan completed a 3.25 year project on exhaust catalysts for gasoline vehicles that exhibit higher activity at lower temperatures down to 150°C. Ford has successfully used catalysts on cars and trucks to control emissions for over forty years. Changes in gasoline engine technology have allowed the use of “high tech” three-way catalysts (TWCs) to simultaneously control HC (hydrocarbons), CO (carbon monoxide), and NOx (nitrogen oxides) at nearly 100% efficiency. Excess fueling is used upon engine start to heat the catalyst up to its full operating temperature of greater than 350°C, lowering fuel economy and creating particulate matter. It was desirable to develop new catalysts for lower operating temperatures that may occur with future, more efficient gasoline powered vehicles, while still being durable to 150,000 mi with peak temperatures of 960°C. The work included laboratory preparation, aging, and poisoning of catalyst materials, activity tests, and chemical analyses. The objective of this project was to demonstrate progress toward the USDRIVE goal of achieving durable 90% conversion (T90) of hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) at 150°C. The project partners focused on several supported metal catalyst structures to promote lower light-off temperatures, enhance metal-support interaction, and improve durability. The raw materials (oxides of aluminum, cerium, silicon, titanium, and zirconium) were not new, but were used in novel ways. Palladium (Pd) or rhodium (Rh) were supported either on layered metal oxide supports, on nanoparticles, or used in various core@shell configurations. Catalyst materials were aged hydrothermally to a simulated high mileage. The catalyst formulation with the lowest durable light-off was 0.5 wt% Rh supported on alumina with an overlayer of either Ti or Zr. The temperatures for 90% conversion were up to 128°C lower than those of a commercial Pd three-way catalyst that had > 3x metal loading of the new Rh catalyst. An additional material made of Pd supported on nanoparticles of ceria-zirconia (CZO) was also considered; the aged T90s were up to 40°C lower than the commercial catalyst, at similar metal loading. Further understanding of the catalyst architecture provided additional confidence to move forward with scale-up of 0.5 wt% Rh/Ti/Al 2 O 3 to coated monolith laboratory cores for further evaluation. The team worked with Johnson Matthey to accomplish this, in addition to exploring manufacturability and potential costs. The overall benefit was estimated to be 10-15% lower NMOG and NOx tailpipe emissions on a cold start certification cycle.
02 PETROLEUM↗
Soiling of building envelope surfaces and its effect on solar reflectance – Part II: Development of an accelerated aging method for roofing materials
Highly reflective roofs can decrease the energy required for building air conditioning, help mitigate the urban heat island effect, and slow global warming. However, these benefits are diminished by soiling and weathering processes that reduce the solar reflectance of most roofing materials. Soiling results from the deposition of atmospheric particulate matter and the growth of microorganisms, each of which absorb sunlight. Weathering of materials occurs with exposure to water, sunlight, and high temperatures. This study developed an accelerated aging method that incorporates features of soiling and weathering. The method sprays a calibrated aqueous soiling mixture of dust minerals, black carbon, humic acid, and salts onto preconditioned coupons of roofing materials, then subjects the soiled coupons to cycles of ultraviolet radiation, heat and water in a commercial weatherometer. Three soiling mixtures were optimized to reproduce the site-specific solar spectral reflectance features of roofing products exposed for 3 years in a hot and humid climate (Miami, Florida); a hot and dry climate (Phoenix, Arizona); and a polluted atmosphere in a temperate climate (Cleveland, Ohio). A fourth mixture was designed to reproduce the three-site average values of solar reflectance and thermal emittance attained after 3 years of natural exposure, which the Cool Roof Rating Council (CRRC) uses to rate roofing products sold in the US. This accelerated aging method was applied to 25 products₋single ply membranes, factory and field applied coatings, tiles, modified bitumen cap sheets, and asphalt shingles₋and reproduced in 3 days the CRRC's 3-year aged values of solar reflectance. In conclusion, this accelerated aging method can be used to speed the evaluation and rating of new cool roofing materials.
54 ENVIRONMENTAL SCIENCES↗
Miniature ESR spectrometer for age dating Martian surface materials
Explore the source record for details and available documents.
ESR age dating Martian surface materials spectrome↗
Effect of aging on lignin content, composition and enzymatic saccharification in Corymbia hybrids and parental taxa between years 9 and 12
Corymbia (a eucalypt) is an important forestry genus and a potential lignocellulosic bioenergy feedstock. The composition of the lignocellulosic cell wall significantly impacts pretreatment efficiency and conversion to biofuel but is variable and changes with age. In this study, we estimated Klason lignin content, composition, and monosaccharide (glucose and xylose) release after enzymatic saccharification of untreated and hydrothermally pretreated biomass from Corymbia parental species Corymbia torelliana (CT), Corymbia citriodora subsp. variegata (spotted gum; CCV), and interspecific F1 hybrids (CT x CCV) at ages 9 and 12 years from planting. Analysis of lignin composition derived from syringyl/guaiacyl monolignols (S/G) found significant differences among taxa, with CT S/G ratios (2.2 and 2.0) being significantly lower than CCV (2.6 and 2.3) or hybrids (2.5 and 2.3) at ages 9 and 12 respectively. In general, enzymatic saccharification yields from untreated biomass were significantly different among taxa, with CT (113 and 75 mg g -1 ) and hybrids (108 and 81 mg g -1 ) yielding significantly higher glucose from untreated biomass than CCV (82 and 56 mg g -1 ) at ages 9 and 12 respectively. Comparison of traits within taxa between ages 9 and 12 found S/G ratios and glucose yields from untreated biomass were significantly lower in CT, CCV and hybrid taxa. As a result, the formation of lignocellulosic cell walls is complex, influenced by genetics and age of material, requiring optimization of rotation age for biofuel production and other industrial processes.
09 BIOMASS FUELS↗
Status of Cable Aging Knowledge Gaps Identified in the Expanded Materials Degradation Assessment (EMDA)
This report summarizes research relevant to cable aging knowledge gaps identified in NUREG/CR-7153, “Expanded Materials Degradation Assessment (EMDA) Volume 5: Aging of Cables and Cable Systems” (EMDA Vol. 5), performed since the EMDA Vol. 5 was published in 2014. It begins with a discussion of the status of cables in long-term operation of U.S. nuclear power plants (NPPs) and the most common cables found in NPP containment. Next, the major polymer cable insulations, and the mechanisms of concern for degradation of those polymers in service are reviewed. A description of the environmental qualification (EQ) process historically used for safety-related cables is provided as is a review of the potential concerns with that process highlighted in the EMDA Vol. 5. Research addressing each of these is then reviewed. Finally, three potential strategies to support continued safe operation of aging cables are proposed: advanced condition-based verification, targeted material aging studies, and predictive simulation.
42 ENGINEERING↗
The chemistry and age of Apollo 11 lunar material
Apollo 11 lunar rocks, breccias and fines age and chemistry, major element, trace element and rare earth abundances, texture, crystallization and meteoritic effects
Arriens, P. A.↗