Results for “static testing” — Page 6

DOE OSTI2020

Calculation of Critical Heat Flux Using an Inverse Heat Transfer Method to Support TREAT Experiment Analysis

Heat transfer between cladding and coolant during transient scenarios remains a critical area of uncertainty in understanding nuclear reactor safety. To advance the understanding of transient and accident scenarios involving critical heat flux (CHF), an in-pile experiment for the Transient Reactor Test (TREAT) facility at Idaho National Laboratory was developed. The experiment named CHF-Static Environment Rodlet Transient Test Apparatus (CHF-SERTTA), consists of a hollow borated stainless steel heater rod submerged in a static water pool which is heated via the (n, a) reaction in boron-10. This paper presents a novel inverse heat transfer method to determine CHF by using the optimization and uncertainty software DAKOTA to calibrate a RELAP5-3D model of CHF-SERTTA to temperature measurements obtained from a thermocouple welded to the surface of the rod.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2022

High strain rate deformation of aged TRIP Ti-10V-2Fe-3Al (wt.%) examined by in-situ synchrotron X-ray diffraction

Transformation Induced Plasticity (TRIP) is a promising avenue for tailoring the work hardening response of metastable $β$ titanium (Ti) alloys. Here we show that aged TRIP Ti-10V-2Fe-3Al (wt.%) maintains higher elongations and flow stresses as strain rate increases, if phase stability and microstructural characteristics are tuned. Low temperature aging influences the matrix $β$ phase stability by $ω$ phase precipitation, which affords a promising way to impact the TRIP effect and obtain desirable mechanical properties, ranging from high damping capacity to good strength/ductility combinations. Although TRIP is active during quasi-static and dynamic testing up to 2000 s –1 , increasing aging time and/or strain rate reduces the overall propensity for the TRIP effect and extent of transformation, which occurs rapidly just at the onset of yielding. Importantly, TRIP with $ω$ phase precipitation provides interesting alloying, microstructure, and property design strategies for engineering applications like lightweight protective structures, where high strains and the need for energy absorption are encountered.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Microstructure and fracture toughness characterization of three 9Cr ODS EUROFER steels with different thermo-mechanical treatments

Ferritic martensitic ODS steels are one of the candidate structural materials for future Gen-IV nuclear fission and fusion reactors. Here, the dependence of fracture toughness on microstructure was investigated by comparing three 9Cr ODS EUROFER steels manufactured through different thermo-mechanical processing routes. Quasi-static fracture toughness testing was performed with sub-sized C(T) specimens and microstructural characterization was carried out using scanning electron microscopy, electron backscatter diffraction, and transmission electron microscopy. It was found that at lower test temperatures (-100 – 22 °C), the fracture toughness was primarily controlled by crack initiation at sub-micron particles and by production of secondary cracks during fracture. At higher temperatures (above 100 °C), fracture toughness was predominantly controlled by the matrix ductility and the grain boundary strength with a relatively ductile coarse-grained alloy demonstrating higher fracture toughness compared to high-strength fine-grained alloys. These results and discussion show that variations in thermomechanical treatments can produce significant differences in microstructure and fracture toughness behavior of ferritic martensitic ODS steels.

36 MATERIALS SCIENCE↗

DOE OSTI2024

Dry Printing Pure Copper with High Conductivity and Adhesion for Flexible Electronics

Additive manufacturing of functional devices on various rigid and flexible substrates is rising rapidly due to their design flexibility, rapid manufacturing, and lower cost. Current printing technologies are ink-based and focused on printing silver (Ag) as conductive lines due to its matured ink formulation process, low sintering temperature, ease of printing, and low oxidation rate. However, Ag is the 68th most abundant element on Earth, while copper (Cu) is the 25th, making it much cheaper (>100×) while having a comparable conductivity to Ag. Therefore, printing Cu has become technologically and economically more attractive than Ag. Nevertheless, Cu printing is still a significant challenge in ink-based printing methods due to the higher sintering temperature relative to the glass-transition temperature of most flexible substrates, the higher oxidation rate, the challenging ink formulation process, and ink stability concerns. Here, we demonstrate printing highly conductive Cu on flexible polyimide substrates using a dry printing technique. Cu nanoparticles (~3–30 nm) are generated by on-demand laser ablation of a solid Cu target inside the printer head and under argon background gas. These Cu nanoparticles are then transported through a nozzle and onto the substrate, where they are laser-sintered in real time. The argon gas plays three critical roles in laser plume condensation for nanoparticle generation, transport, and sheath gas to avoid oxidation during sintering. The sintered nanoparticles thus show high electrical conductivity and mechanical stability under static and cyclic tests. Our dry printing technique can potentially revolutionize how electronic devices and sensors are additively manufactured for earth and space applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2022

Activity gradient driven mass transport in molten fluoride salt medium

Abstract The molten salt-cooled reactor concept has garnered significant interest and one of the current challenges limiting the deployment of these reactor concepts is the complex corrosion phenomenon observed in molten salt environments. One of these phenomena is activity gradient mass transport, which has been shown to affect dissimilar materials submerged in the same salt medium even when best efforts have been made to electrically isolate dissimilar materials from one another. This mechanism while shown experimentally, has not been predictively studied through a modeling approach. In this study, activity gradients in several 316L-X materials systems have been modeled and the mass transport predicted by the model has been confirmed through static isothermal corrosion testing in a molten fluoride salt medium.

36 MATERIALS SCIENCE↗

DOE OSTI2022

High speed ultraviolet digital image correlation (UV-DIC) for dynamic strains at extreme temperatures

Digital Image Correlation (DIC) is a camera-based method of measuring full-field displacements and strains from the surface of a deforming object. It can be applied at any length scale (determined by the lenses) and any time scale (determined by the camera), and because it is non-contacting, it can also be used at temperatures much higher than can be withstood by bonded strain gauges. At extreme temperatures, materials emit light in the form of blackbody radiation, which can saturate the camera sensor. It has previously been shown that the emitted light can be effectively screened by using ultraviolet (UV) cameras, lenses, and filters; however, commercially available UV cameras are relatively slow, which limits the speed of combined UV-DIC measurements. In this study, a UV intensifier was paired with a high-speed camera, and its ability to perform UV-DIC at high temperature and high speed was investigated. The system was compared over three different experiments: (A) a quasi-static thermal expansion test at high temperature, (B) a vibration test at room temperature, and (C) the same vibration test repeated at high temperature. The system successfully performed DIC up to at least 1600 °C at frame rates of 5000 fps, which is more than 100 times faster than other examples of UV-DIC in the literature. In all cases, measurements made using the UV intensifier were much noisier than those made without the intensifier, but the intensifier enabled measurements at temperatures well above those which an unfiltered high-speed camera otherwise saturates.

47 OTHER INSTRUMENTATION↗

DOE OSTI2022

FIC Vulnerability Profile

The FIC team is engaged with Pacific Northwest National Laboratory’s (PNNL’s) Shamrock Cyber Team to provide cybersecurity analyses of the FIC software. Shamrock offers both Threat-Based Analysis services and Secure Software Development services. These services are ultimately used to understand and mitigate threats against software and to reduce vulnerabilities in software, thus improving overall cybersecurity and informing decision makers. Shamrock’s Secure Software Development services, specifically Static Analysis Security Testing (SAST) and Open-Source Analysis (OSA), produced this Vulnerability Profile.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2024

Structural Characterization of Deployed Thermoplastic and Thermoset Composite Tidal Turbine Blades

The National Renewable Energy Laboratory worked with Verdant Power to manufacture, and characterize, novel thermoplastic composite blades on their Gen5d 5 m diameter turbines at the Roosevelt Island Tidal Energy (RITE) site in the East River in N.Y. to demonstrate a low-cost manufacturing process for marine energy structures. Verdant had designed, manufactured, and deployed epoxy thermoset composite blades on three Gen5d turbines in October 2020. At a maintenance cycle in May 2021, a Gen5d turbine equipped with the NREL thermoplastic blades was deployed and retrieved in October 2021. Modal, static and fatigue structural characterization was performed on both blade types before and after the deployment. The static and modal test results showed that the thermoplastic blades were slightly stiffer than the epoxy blades both dry and after the deployment. The epoxy blades had about 8% increase in strain at the applied load after the deployment, whereas the thermoplastic blade strains were not changed significantly. Ultimately the thermoplastic blade failed during fatigue testing due to a crack which is thought to have initiated between the internal foam and the laminate at the location of the internal instrumentation. The Verdant Power Gen5d epoxy blades did not have this internal instrumentation and did not have this failure, performing adequately through the operational period. A lack of design information and fatigue data for both the thermoplastic laminates and the adhesive used means that further work is needed to fully understand his failure and the root cause analysis is ongoing. This paper provides details on the thermoplastic blade manufacturing, materials, test methodology and results.

17 WIND ENERGY↗

DOE OSTI2025

TEAMER Technical Support on Biofouling and Corrosion for E-Wave Technologies LLC Novel (Abstract)

National Technology & Engineering Solutions of Sandia (NTESS) in collaboration with the Pacific Northwest National Laboratory (PNNL), and with guidance from E-Wave, will assess corrosion and biofouling challenges specific to E-Wave’s innovative WEC designed to retrofit into and power existing aquaculture farm infrastructure from ocean waves. The teams will examine coatings via a static raw seawater test and determine the efficacy of coatings for E-Wave’s applications. Samples will include panels of materials provided by E-Wave and coated with three different paint treatments. Fouling will be determined using a staining technique followed by photographic analysis to evaluate fouling intensity on the surface. Materials will also be weighed before and after submersion to facilitate weight change analysis resulting from fouling organisms aggregating on the materials.

16 TIDAL AND WAVE POWER↗

DOE OSTI2025

FY25 Cellular Silicone Foam Friction Testing Summary Report

This effort was a collaboration between LANL groups MPA-CINT, E-13, and V-14 to characterize various properties of foam materials for programmatic work. Specifically, MPA-CINT staff members’ contribution to this effort was to perform friction testing of cellular silicone foams of two different porosities with respect to two engineering materials with predefined surface roughnesses. The selected foams (henceforth serving as the sled material interface exposed to motion) had porosities of 67% and 70% with respect to fabricated values. The other materials used in the friction testing measurement couple (static track material) were 304 Stainless Steel (304 SS) and Very High-Temperature Glass-Mica Ceramic, known as Macor®.

36 MATERIALS SCIENCE↗

DOE OSTI2025

SULI Intern Final Report: Computationally Investigating Hydrogen Thermo-Diffusion in Yttrium Hydride Using Multiscale Methods

The renaissance of nuclear energy has arrived, heralding an age of abundant inexpensive clean energy, and renewed space exploration. In nuclear-powered spacecraft and microreactors, safety and size are of utmost importance. Yttrium Hydride (YHx) is being researched for its utility as a neutron moderator in nuclear reactors; the hydrogen in YHx slows down neutrons, enabling a continuous nuclear reaction in the reactor. This has the benefit of allowing reactors to be more safe, compact, and efficient. The goal of this effort is to computationally predict the coefficient of temperature-dependent hydrogen diffusion within YHx, the Soret coefficient. This parameter is essential for determining the safe operating modes of YHx moderators. Zirconium Hydride (ZrHx) is used in the Training, Research, Isotopes, General Atomics (TRIGA) reactor, is the reference material for these calculations. In this work, nanoscale atomic modeling in the Vienna Ab initio Simulation Package (VASP) is combined with the mesoscale finite element phase-field module in the Multiphysics Object-Oriented Simulation Environment (MOOSE); this culminates in a new multiscale computational method to simulate Soret diffusion of hydrogen in YHx. This data is useful for predicting experimental outcomes. This workflow involves convergence testing followed by static, Nudged Elastic Band (NEB), Quasi-Harmonic Approximation (QHA), and Molecular Dynamics (MD) calculations - linked with phase field simulation. NEB simulates hydrogen migration, while QHA and MD predict temperature-dependent properties. The static calculations align with literature, and preliminary NEB and QHA calculations yield accurate results. Once the atomic calculations are complete, we will incorporate Electron Backscatter Diffraction (EBSD) images and VASP-generated parameters into the phase field module to simulate intra- and intergranular transport of hydrogen in ZrHx and YHx. Future research will extend our approach to fuel-moderator materials systems such as Uranium-Yttrium Hydride (U-YHx). This work contributes to the development of advanced nuclear energy solutions for space travel.

36 - MATERIALS SCIENCE↗

DOE OSTI2020

Recovery of Cs-137 from Electric Arc Furnace Dust - 20562

The present work proposes the Cs-137 recovery from Electric Arc Furnace Dusts (EAFD) by leaching, in order to reduce the volume of radioactive waste to be managed. Leaching tests were performed on different samples of EAFD contaminated with Cs-137. Two leaching methodologies were tested: dynamic and static using as medium distilled water and in some cases NaOH. The results indicate the possibility of recovering Cs-137 from EAFD using the dynamic method; however, the recovery efficiencies of Cs-137 depend on EAFD's chemical composition. The leachates of Cs-137 were quantitatively adsorbed on exchange resins, showing its great potential to isolate or contain the Cs-137 recovery from EAFD. This study shows the feasible to apply the dynamic leaching methodology to recover Cs-137 from EAFD and the use of ion exchange resins for the isolation of removed Cs-137. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

Pre-Transient Characterization of Historic EBR-II Pins for Transient Testing

Current interest in sodium-cooled fast reactor (SFR) designs, such as TerraPower’s Natrium Reactor, has highlighted the need for advanced reactor fuel technology development. Modern U-Zr and U- Pu-Zr pin designs are primary candidates to fuel SFRs and boast high fuel utilization capacity, increased fuel-cladding compatibility, and improved safety through inherent feedback mechanisms. Despite over 60 years of metallic fuel irradiation, uncertainties exist in the performance of the fuel system, particularly under transient overpower (TOP) and loss of flow (LOF) scenarios. Throughout historical testing within the Experimental Breeder Reactor II (EBR-II) and the Fast Flux Test Facility (FFTF), fuel behavior has demonstrated benign response to transient reactor conditions; however, accurate predictions of failure thresholds to inform operational limitations rely heavily on fuel composition, burnup, and irradiation history. In expanding TOP and LOF testing, the Transient Heat sink Overpower Response (THOR) Capsule will be used to test modern fuel technologies in a static sodium environment in the Transient Reactor Test (TREAT) Facility. The THOR capsule is highly instrumented and will provide time-dependent thermal behavior of SFR fuel pins subjected to accident conditions within TREAT. The THOR-Metallic (THOR- M) campaign aims to validate and expand historical TOP and LOF testing on high burnup U-Zr and U-Pu- Zr fuel alloys previously irradiated in EBR-II by running the rods to failure. This contribution focuses primarily on the pre-transient engineering-scale destructive and non- destructive characterization that has been conducted on both the test and sibling pins used for the TOP and LOF tests. All pins underwent visual examination, neutron radiography, element contact profilometry, and precise gamma scan. The sibling pins used for each test were further analyzed using gas assay, sampling, and recharge analysis (GASR), and optical microscopy. The results from each technique confirmed that the fuel pins were intact and devoid of any atypical developments when compared to historical data. Additionally, the analyzed measurements establish a baseline for comparison to post-transient analysis. Key fuel behaviors quanitifed include axial elongation of the fuel column, diametral strain of the pin, patterns in fluff structure geometry, changes in axial isotope distribution, evolution of constituent redistribution, porosity, and fission gas release. The pre-transient measurements and changes attributed to transient behavior from post-transient measurement will be compared to historical data to capture the behavioral dependence on composition, burnup, and irradiation history. Results from this work advance the initiatives of the THOR-M campaign, which aid in informing fuel performance models and establishing safety criteria for SFR operational limits. The novel combination of test environment, in-situ instrumentation, and comprehensive suite of characterization methods provides greater understanding of transient fuel behavior. Overall, information on the time and condition of pin failure for high burnup U-Pu-Zr will greatly expand the limited existing TOP and LOF test data.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2024

Pre-Transient Characterization of Historic EBR-II Pins for Transient Testing

Current interest in sodium-cooled fast reactor (SFR) designs, such as TerraPower’s Natrium Reactor, has highlighted the need for advanced reactor fuel technology development. Modern U-Zr and U- Pu-Zr pin designs are primary candidates to fuel SFRs and boast high fuel utilization capacity, increased fuel-cladding compatibility, and improved safety through inherent feedback mechanisms. Despite over 60 years of metallic fuel irradiation, uncertainties exist in the performance of the fuel system, particularly under transient overpower (TOP) and loss of flow (LOF) scenarios. Throughout historical testing within the Experimental Breeder Reactor II (EBR-II) and the Fast Flux Test Facility (FFTF), fuel behavior has demonstrated benign response to transient reactor conditions; however, accurate predictions of failure thresholds to inform operational limitations rely heavily on fuel composition, burnup, and irradiation history. In expanding TOP and LOF testing, the Transient Heat sink Overpower Response (THOR) Capsule will be used to test modern fuel technologies in a static sodium environment in the Transient Reactor Test (TREAT) Facility. The THOR capsule is highly instrumented and will provide time-dependent thermal behavior of SFR fuel pins subjected to accident conditions within TREAT. The THOR-Metallic (THOR- M) campaign aims to validate and expand historical TOP and LOF testing on high burnup U-Zr and U-Pu- Zr fuel alloys previously irradiated in EBR-II by running the rods to failure. This contribution focuses primarily on the pre-transient engineering-scale destructive and non- destructive characterization that has been conducted on both the test and sibling pins used for the TOP and LOF tests. All pins underwent visual examination, neutron radiography, element contact profilometry, and precise gamma scan. The sibling pins used for each test were further analyzed using gas assay, sampling, and recharge analysis (GASR), and optical microscopy. The results from each technique confirmed that the fuel pins were intact and devoid of any atypical developments when compared to historical data. Additionally, the analyzed measurements establish a baseline for comparison to post-transient analysis. Key fuel behaviors quanitifed include axial elongation of the fuel column, diametral strain of the pin, patterns in fluff structure geometry, changes in axial isotope distribution, evolution of constituent redistribution, porosity, and fission gas release. The pre-transient measurements and changes attributed to transient behavior from post-transient measurement will be compared to historical data to capture the behavioral dependence on composition, burnup, and irradiation history. Results from this work advance the initiatives of the THOR-M campaign, which aid in informing fuel performance models and establishing safety criteria for SFR operational limits. The novel combination of test environment, in-situ instrumentation, and comprehensive suite of characterization methods provides greater understanding of transient fuel behavior. Overall, information on the time and condition of pin failure for high burnup U-Pu-Zr will greatly expand the limited existing TOP and LOF test data.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2020

Overview of 2016 through 2018 Testing of Air-Purifying Respirator (APR) Cartridge Performance on Multiple Hanford Tank Headspaces and Exhausters

Between 2016 and 2018, 28 air purifying respirator (APR) cartridge tests were performed on headspace vapors from seven Hanford waste storage tanks (SY-102, A-101, BY-108, AX-101, BY-110, SX-101, and SX-104) and seven waste tank exhausters (AP in 2016, AP in 2018, 702-AZ, AN and AW in 2016, and AX and 702-AZ in 2017). All but two tests were conducted under static conditions absent waste-disturbing activities in the subject tanks or tank farms. The two exceptions were cartridges tested with vapors from 702-AZ in 2017 when samples were taken during waste-disturbing activities. Multipurpose APR cartridges, SCOTT 7422-SD1 and 7422-SC1, were tested on samples from each of the 14 tanks or exhausters. Out of 612 Chemicals of Potential Concern (COPCs), only ammonia, mercury, N-nitrosodimethylamine (NDMA), 2,5-dimethylfuran, 2,5-dihydrofuran, furan, and 1,3-butadiene exhibited breakthroughs with outlet concentrations that were >10% of their Occupational Exposure Limits (OEL).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

A New Simple-to-Configure Self-Perturbing Multivariable Extremum-Seeking Controller

This paper presents a new stochastic relay-based extremum-seeking controller (ESC) for multi-input-single-output (MISO) systems. The algorithm was developed with the goal of simplifying configuration to enable easier deployment to real-world problems. A solution is developed first for a static map and then adapted for a general class of dynamic systems. The number of configurable parameters is one per input channel for the static case and only one additional parameter is needed for the dynamic version. The problem of gradient identifiability is solved via the use of stochastic relay gains and a simple stability proof for the static case is presented. Simulation tests demonstrate the performance of the strategy for optimizing both static and dynamic systems.

Salsbury, Timothy [BATTELLE (PACIFIC NW LAB)]↗

DOE OSTI2020

Analyzing the Validity of Brazilian Testing Using Digital Image Correlation and Numerical Simulation Techniques

Characterizing the mechanical behavior of rocks plays a crucial role to optimize the fracturing process in unconventional reservoirs. However, due to the intrinsic anisotropy and heterogeneity in unconventional resources, fracture process prediction remains the most significant challenge for sustainable and economic hydrocarbon production. During the deformation tracking under compression, deploying conventional methods (strain gauge, extensometer, etc.) is insufficient to measure the deformation since the physical attachment of the device is restricted to the size of the sample, monitoring limited point-wise deformation, producing difficulties in data retrieval, and a tendency to lose track in failure points, etc. Where conventional methods are limited, the application of digital image correlation (DIC) provides detailed and additional information of strain evolution and fracture patterns under loading. DIC is an image-based optical method that records an object with a camera and monitors the random contrast speckle pattern painted on the facing surface of the specimen. To overcome the existing limitations, this paper presents numerical modeling of Brazilian disc tests under quasi-static conditions to understand the full-field deformation behaviors and finally, it is validated by DIC. As the direct tensile test has limitations in sample preparation and test execution, the Brazilian testing principle is commonly used to evaluate indirectly the tensile strength of rocks. The two-dimensional numerical model was built to predict the stress distribution and full-field deformation on Brazilian disc under compression based on the assumptions of a homogenous, isotropic and linear elastic material. The uniaxial compression test was conducted using the DIC technique to determine the elastic properties of Spider Berea sandstone, which were used as inputs for the simulation model. The model was verified by the analytical solution and compared with the digital image correlation. The numerical simulation results showed that the solutions matched reasonably with the analytical solutions where the maximum deviation of stress distribution was obtained as 14.59%. The strain evolution (normal and shear strains) and displacements along the central horizontal and vertical planes were investigated in three distinguishable percentages of peak loads (20%, 40%, and 90%) to understand the deformation behaviors in rock. The simulation results demonstrated that the strain evolution contours consistently matched with DIC generated contours with a reasonable agreement. The changes in displacement along the central horizontal and vertical planes showed that numerical simulation and DIC generated experimental results were repeatable and matched closely. In terms of validation, Brazilian testing to measure the indirect tensile strength of rocks is still an issue of debate. The numerical model of fracture propagation supported by digital image correlation from this study can be used to explain the fracturing process in the homogeneous material and can be extended to non-homogeneous cases by incorporating heterogeneity, which is essential for rock mechanics field applications.

58 GEOSCIENCES↗

DOE OSTI2021

Results of the CHF-SERTTA In-Pile Transient Boiling Experiments at TREAT

To advance the current understanding of heat transfer between nuclear fuel rod cladding and the surrounding coolant under transient scenarios involving critical heat flux (CHF), the CHF-Static Environment Rodlet Transient Test Apparatus (CHFSERTTA), an in-pile experiment, was developed for and irradiated in the Transient Reactor Test (TREAT) facility at Idaho National Laboratory. The CHF-SERTTA experiment consists of a hollow, borated stainless steel rod submerged in a static water pool. The rod, heated via the (n, a) reaction in boron-10, was designed for investigating in-pile transient heat transfer between the rod surface and the coolant, avoiding the complexity of including the heat transfer between the fuel, gas gap, and cladding in typical light-water reactor (LWR) fuel rods. The instrumentation package for CHF-SERTTA focused on capturing those data that best describe the heat transfer behaviour between the rod and coolant. This paper outlines the CHFSERTTA experiment design and presents the initial results of the experiment campaign.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗