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This poster is to show the strength after oxidation of NBG-17 graphite at various mass loss percentages. This data is compared to previous data that had no standards of testing to establish an ASTM standard for future application.
NREL and the Clean Fuels Alliance America (CFAA) will work cooperatively to assess the effects of biodiesel blends on the performance of modern diesel engines. This work will include research to understand the impact of biodiesel blends on the operation and durability of particle filters and NO x control sorbents/catalysts, to quantify the effect on emission control systems performance, and to understand effects on engine component durability. This research was performed at NREL Renewable Fuels and Lubricants (REFUEL) laboratory (an engine testing laboratory) as well as at third party labs paid directly by CFAA with NREL as part of the project management team. Also, research to develop appropriate ASTM standards for biodiesel quality and stability was conducted in NREL’s bench scale fuel chemistry laboratory. The cooperative project involved laboratory testing and research at NREL using biodiesel from a variety of sources and in collaboration with a broad range of other stakeholders. In addition, NREL will work with NBB to set up an Industrial Steering Committee to design the scope for the various tasks and to provide technical oversight to these projects. NREL and NBB will cooperatively communicate the study results to as broad an audience as possible. This research benefits the public by expanding markets for a domestically produced low-carbon intensity fuel for use in diesel engines.
Discuss the SiC passive thermometry methods currently performed at INL and ORNL, decide on best path forward for establishing an ASTM Standard for processing SiC temperature monitors, and expand this ASTM benchmarking efforts to international collaborators (Netherlands, Canada, and Poland).
Here, in this article, a miniature dog bone tensile coupon design was tested against the existing ASTM standard specimen design. Specimens were prepared from commercially sourced austenitic stainless steel 304 alloy, and a defect-ridden additively manufactured 304L alloy was studied. By utilizing a tensile specimen design that is 1/230th volume of the smallest ASTM E8-04(2016), Standard Test Methods for Tension Testing of Metallic Materials, dog bone specimen, coupled to a digital image correlation (DIC) setup, case studies were performed to compare tensile property measurements and strain field evolution. Whereas yield strength measurements were observed to be similar, post-yield, the ultimate strength measurements and ductility measurements from the miniature specimens were observed to be higher than the ASTM specimen design. Although the strength measurements were comparable, the strain evolution was found to differ in the miniature specimens. Studies to assess effects of varying thickness and defect population were also pursued on the miniature tensile specimen. From the DIC strain field estimations, the peak local strain values at ultimate tensile strength were observed to be increasing with reducing specimen thickness. Testing of defect ridden stainless steel revealed the sensitivity to failure through strain localization and the influence of defect size was captured in the strength measurements.
Sensors and sensor systems for monitoring fine particles with aerodynamic diameters smaller than 2.5 µm can provide real-time feedback on indoor air quality and thus can help guide actions to manage indoor air pollutant concentrations. Standardized verification of the performance and accuracy of sensors and sensor systems is crucial for predicting the efficacy of such monitoring. A new ASTM International standard test method (ASTM D8405) was created for this need and is the most exacting laboratory protocol published to date for evaluating indoor air quality sensors and sensor systems measuring particles smaller than 2.5 µm in diameter. ASTM D8405 subjects sensors and sensor systems to five test phases: (1) an initial particle concentration ramp; (2) exposure to various temperature and humidity conditions; (3) exposure to interfering particles; (4) temperature cycling; and (5) a final particle concentration ramp to assess drift. This paper discusses the development of the standard test method, key aspects of the testing process, example evaluation results, and a comparison of this standard test method against peer evaluation protocols.
The crack tip opening angle (CTOA) is one of fracture toughness parameters that has been used for decades in describing large stable crack growth in thin-walled aerospace structures under the low-constraint conditions. Recently, the pipeline industry has developed a growing interest in using the CTOA parameter to serve as the minimum required fracture toughness to arrest dynamic crack propagation in modern gas transmission pipelines made of high-strength ductile steel. To meet this industrial need, the CTOA test standard ASTM E3039 was therefore developed for measuring the constant critical CTOA. ASTM E3039 recommends a drop weight tearing test (DWTT) specimen with a shallow crack for standard CTOA testing, but its CTOA may depend on the low constraint condition of the DWTT specimen at the crack tip. Verifying the constraint independence of the DWTT-measured CTOA thus becomes indispensable for applying CTOA toughness to the running fracture control in the pipeline design. For this purpose, the present paper evaluates critical CTOA values in a set of fracture toughness tests on single-edge notched bend (SENB) specimens with shallow and deep cracks, based on four CTOA estimation models. Among these, the Ln(P)-LLD linear fit model is similar to that recommended by ASTM E3039 for CTOA calculation. Fracture test data for X80 pipeline steel and HY80 structural steel were considered in the CTOA evaluation. The results showed that the four CTOA models were able to determine a constraint independent CTOA value for stable crack growth in the SENB specimens. As a result, a single, reliable, constant CTOA value could be determined regardless of the specimen geometry or the crack-tip constraint conditions. Therefore, the CTOA measured using ASTM E3039 is constraint-independent and transferable to use in cases of actual cracks propagating in gas transmission pipelines.
The development of a new ASTM standard for evaluating the corrosion resistance of additive manufactured (AM) stainless steel (SS) 316H in chloride molten salts is critical for the use of these materials in extreme environments such as molten salt reactors (MSRs). This report pertains to a work package of the Advaned Materials and Manufacturing Technologies (AMMT) developing a systematic methodology to link changes in AM fabrication parameters, namely surface finishing, porosity, microstructure, and chemical heterogeneity, to corrosion performance in NaCl-MgCl2 salt, a proposed secondary coolant for MSRs. During Fiscal Year 2024, Idaho National Laboratory investigators in the AMMT program, utilized SS316H bars, fabricated with laser bed powder fusion at Los Alamos National Laboratory, to establish and optimize the workflow for evaluating these process-to-performance relationships. Standard practices for specimen preparation were established using these specimens, with particular focus on descaling and sectioning methods that align with ASTM guidelines. A comprehensive experimental design for static corrosion testing was developed, with pre- and post-exposure analysis utilizing optical microscopy and scanning electron microscopy. So far standard descaling techniques were optimized, one static corrosion test was conducted on the LANL AM SS316H specimens, and pre- and post-corrosion practices were established. In addition, the work package yielded a review paper on corrosion testing gaps for AM materials in nuclear applications and submitted a proposal for a rapid-turnaround experiment to the Nuclear Science User Facilities Program to investigate the combined effects of proton irradiation and corrosion on AM SS316H. This work package establishes a foundation for evaluating processing-to-performance relationships for AM SS316H in harsh conditions, contributing to the safe and efficient design of components for next-generation nuclear reactors. The creation of a standardized methodology and the generation of relevant publications and future research pathways represent significant strides towards integrating AM materials into critical applications where corrosion resistance is paramount.
Window openings in walls are a significant contributor to poor thermal performance because of thermal bridging through the framing members (e.g., studs, joists, plates, bracing) and because windows lack the thermal properties of insulation. Window installation guidance for walls with continuous insulation (CI) is critical for continued market growth of this energy efficiency technology. This research project offers window manufacturers a starting point and a potential path toward developing installation instructions for windows over CI. The objectives of the research include evaluating the common method for installing windows in walls with CI, as well as establishing acceptance criteria for evaluating the performance of windows installed in walls with and without CI. The research measures: 1. The performance characteristics (e.g., water management, structural integrity) of windows in walls without CI. 2. The performance of different thicknesses and types of CI used in walls. 3. The performance of different types of window assemblies (e.g., double-hung windows, mulled double-hung windows, mulled casement windows, and slider windows) installed over CI. 4. The performance of window flange types (e.g., rigid mounting and less robust flanges) installed over CI. 5. Installing windows over CI using baseline installation instructions versus window manufacturer installation instructions. The project’s sequential testing protocol consists of the following: • A water penetration resistance testing adapted from two ASTM standards: E331 (uniform static air pressure in four steps) and E547 (cyclic static air pressure) • A temperature cycling adapted from ASTM E2264 Method B (convective hot air) • A service condition wind loading test adapted from ASTM E330 • A six-month vertical displacement observation phase prior to the structural performance testing • A final water penetration resistance test after vertical displacement observation • A structural performance test adapted from ASTM E330. Key research findings include: • The criterion for passing a water penetration resistance test is that there is no water overflowing at the interior face of the studs. If there is any bubbling or slight pooling of water at the sill, then it must recede after the pressure is removed. Excessive leakage and/or water leaking to the interior face of the framing around the window constitutes a failure. • All single double-hung windows installed directly to lumber or over oriented strand board passed all test protocols. • For most wall specimens, the test results showed that the use of foam sheathing did not affect the performance of the window for water leakage. • All wall specimens underwent temperature cycling. The results indicated that temperature cycling had little to no effect on windows installed over foam sheathing. • For wall specimens that underwent six-month vertical displacement monitoring, the results showed that windows installed over foam sheathing do not sag over time. • The single-hung and double-hung windows installed using window manufacturer installation instructions passed the structural performance test, compared to failures observed in windows that were installed using generic installation instructions. The generic and manufacturer installation methods differed on the following construction details: type of fasteners, fastening patterns on the flanges, and window shimming details. • Additional testing is required to determine methods to improve structural pressure performance of slider windows. Potential solutions that would require additional testing may include fastener spacing, different types of fasteners, masonry window clips, construction adhesive, foam sealant, stronger window flange material, and/or straps.
This is a presentation regarding A709 Procurement and ASTM Specification Status for the Joint ART Materials/AMMT Program Review meeting. The A709 team consists of Argonne National Laboratory, Idaho National Laboratory, Oak Ridge National Laboratory, and Subject matter expert John Grubb and Richard Wright. Discussion topics will discuss incorporation of 709 into ASTM Standard A 240 for plate material in the solution annealed condition with a precipitation treatment as a supplemental requirement is underway, Incorporation of Alloy 709 into ASME, Section II, Specification SA 240 will be made upon the completion of the ASTM task, The required commercial scale heats of Alloy 709 for property characterization to provide the technical basis for Code qualification have been procured, and Laboratory testing of properties from these three heats is underway as will be discussed separately at this review meeting.
Based on literature analysis, X-ray photoelectron spectroscopy (XPS) use continues to increase exponentially. This increased use is accompanied by anecdotal reports and systematic analyses indicating a growing presence of significantly flawed data analyses. Recognition of this problem within the surface analysis community has increased with an understanding that both inexperienced users and increased use of XPS outside the surface analysis community contribute to the problem. The XPS community has initiated several efforts to help address the problem, which is not unique to XPS. This paper describes some of the specific problems identified and some of the community efforts intended to address them. Here, we describe activities focused on three specific issues: (i) requests for detailed guides and protocols and bite-sized versions of information for non-experts, (ii) incomplete data and analysis reporting, and (iii) the high rate of peak fitting problems. A 2019 survey identified the need for guides, protocols, and standards to assist XPS users. One set of such guides has been published, and another is being assembled. Providing incremental bites of useful information is the goal of a series of papers on specific challenges to surface analysis with example solutions has been initiated as Notes and Insights papers in Surface and Interface Analysis. Examination of XPS-containing papers finds that information to establish the credibility and reproducibility of XPS results is often very incomplete. Unfortunately, ISO and ASTM standards require an amount of parameter reporting that seems excessive and unrealistic for many research publications. Initial approaches to develop and distribute a graded approach to parameter reporting are briefly described. Multiple efforts are underway to address the high rate of problems associated with photoelectron peak fitting. These include guides to peak fitting, guides to peak identification and fitting for specific elements, and the development of a peak fitting social network. The fitting social network is designed to facilitate interactions between new and experienced XPS users; analysts trying to fit XPS data (for publication or other reasons) can ask questions and establish dynamic conversations. Encouraging and enabling high-quality XPS analysis and reporting requires several different types of effort from all members of the surface and interface analysis community.
Under the auspices of International Atomic Energy Agency (IAEA), a coordinated research project (CRP) entitled “Towards the Standardization of Small Specimen Test Techniques for Fusion Applications” has started since 2017. The overall objective of the project is to provide a set of guidelines for small specimen test techniques (SSTT) based on commonly agreed best practices on main test techniques including tensile, creep, low cycle fatigue, fracture toughness, and fatigue crack growth rate. This will act as the first step of a full standardization of the SSTT. Fusion structural materials, i.e., reduced activation ferritic/martensitic (RAFM) steels, are used for testing. In addition, the project will create a comprehensive mechanical property database of RAFM steels tested by SSTT. For the fracture toughness task of the CRP, three testing methods including Master Curve, local approach for ductile crack growth and cleavage fracture, and ductile approach at room temperature will be evaluated. This report focuses on developing guidelines for the round-robin Master Curve testing based on the ASTM standard E1921-19b “Standard Test Method for Determination of Reference Temperature, T 0 , for Ferritic Steels in the Transition Range” and commonly agreed best practice from researchers at Oak Ridge National Laboratory (ORNL), Centre for Energy, Environment and Technology (CIEMAT), and UK Atomic Energy Authority (UKAEA).
Digital Image Correlation (DIC) is an optical technique that combines image registration and tracking methods for accurate two-dimensional and three-dimensional changes in images. DIC software can be used to track the contour, deformation, and strain of a sample. In the Advanced Test Reactor (ATR) at INL (Idaho National Laboratory) there exists a small working window of samples that can become irradiated. Hundreds of graphite disks called piggybacks have undergone this irradiation as part of the Advanced Reactor Technologies (ART) program. After irradiation, it is desirable to understand the change in tensile strength as a function of dose. Due to the limited space in the ATR, typical dog bone tensile tests reduce the number of graphite samples from hundreds to tens. However, there does exist an ASTM standard, D8289, which uses disc compression of graphite to estimate the tensile strength of the specimen with the Brazilian Disk test fixture. While only used as an estimate, which is typically off by a third, it is the purpose of this study to identify how to amend D8289 to remove the word "estimate" with the help of DIC.
Programs at Oak Ridge National Laboratory are investigating the effects of neutron irradiation in the High Flux Isotope Reactor (HFIR) on properties of fine-grain isotropic nuclear graphites. Specimens were irradiated in the HFIR flux trap, which requires using specimens that are smaller than the sizes recommended by ASTM standards. Here, this work has investigated whether subsized specimens can be used to reliably predict strength behavior. The results show that (1) tensile strength was loosely coupled to specimen volume, (2) the compression specimens had a slightly higher strength for larger volumes, (3) the uniaxial flexural strength was nearly independent of specimen effective area for one orientation whereas the other orientation showed a slight strength–size scaling Weibull behavior, and (4) equibiaxial flexural strength followed traditional strength–size scaling Weibull behavior. These results suggest that fine-grain graphite is more similar to ceramics than to medium- and large-grained graphite with respect to both the strength-limiting flaws (Griffith theory) and the effect of machining on the strength behavior. This work shows that using specimens that are smaller than ASTM recommendations are suitable for investigating the strength changes caused by neutron irradiation because the primary interest is the relative change in the strength distribution parameters rather than their absolute values.
The strength of advanced graphite is reported in accordance with ASTM D7846-16 using a two-parameter Weibull distribution for uniaxial strength testing. The rule of thumb for Weibull distributions is to use a minimum of 30 strength measurements to have a high level of confidence in the Weibull characteristic strength and the Weibull modulus. These large sample sets for statistical confidence are easily obtained for as-manufactured graphite, but determination of the Weibull two-factor parameters on graphite that has been exposed to neutron irradiation is nearly impossible due to irradiation testing restraints on specimen size and space limitations in test reactors for the accommodation of specimens. These restrictions have resulted in irradiation programs that use sub-sized specimens to measure uniaxial strength change, but the specimen geometries still hinder the number of replicate specimens for each irradiation condition. In contrast, this work used an advanced ceramic standard, ASTM C1499-05, as the foundation for equibiaxial strength testing of a superfine-grained nuclear graphite to investigate the irradiation-induced strength change and any changes to the two-parameter Weibull distribution. The goal was to investigate the effect of specimen size on the two-parameter Weibull distribution parameters in support of the small specimens and geometry desired for irradiation. A study of the effect of a reduced sample population was also undertaken to investigate the reliability of using the two-parameter Weibull distribution to study changes to the materials properties caused by neutron irradiation damage. The results of this work suggest that these equibiaxial specimens would be ideal for statistically significant studies of the effects of irradiation on the Weibull characteristic strength (but not the modulus) and for providing a method for surveillance specimen campaigns for future operating commercial reactors.
Outgassing of 3D printed and casted silica-filled silicones was studied using a standard ASTM E-595 procedure and a modified Soreq’s method that allows very sensitive measurements of the outgassing kinetics even at low temperatures, 20 – 50 °C. We studied three different silica-filled silicones, non-porous cased M9787, and 3D printed LL50 and 40P materials. The present report shows that vacuum outgassing products of polysiloxane-based materials include multiple species. In addition to chemisorbed and physisorbed water outgassing, previously studied by TPD, polymer fragments of varying sizes evaporate as well. The chemical composition of the condensable volatile species collected on a Germanium substrate, was analyzed by FTIR. It was shown that all studied materials produce mostly PDMS-based outgassing products that form stable droplet-like structure on the Ge substrate. The highest amount of the condensable volatile species was measured for LL50. Isothermal TGA in nitrogen atmosphere of the LL50 material was compared to the standard vacuum outgassing. The results of TGA showed lower mass loss and higher water regain. The kinetics of the outgassing at relatively low temperatures of 20, 30 and 50 °C was studied using Thermoelectric Quartz Crystal Microbalance (TQCM). The TQCM surface was held at -10 °C to enhance condensation of the outgassed moisture. The analysis presented here, when combined with the extensive previous work on moisture outgassing, provides a better understanding of the aging mechanism of polysiloxane-based materials. In this work we show that outgassing techniques, usually applied for qualification of polymers for space-related applications, may be used as a complementary method to study thermal degradation and aging of silica-based silicones. Our results indicate that the long-term degradation mechanics and thermal degradation products depend primarily on the chemical composition of silicone-based material and only slightly affected by the manufacturing process. Surprisingly, the surface-to-volume ratio of the 3D printed vs. casted/molded materials showed only minor effect on the outgassing kinetic parameters.
Abstract Battery‐grade graphite and aviation fuel are traditionally produced from non‐renewable, fossil carbon feedstocks and result in substantial greenhouse gas emissions. Biomass holds exciting potential as a renewable and sustainable feedstock for the production of graphite and aviation fuel, but challenges exist including the necessity of a catalyst when producing graphite and low selectivity when producing aviation fuel. A process to convert a biomass‐derived feedstock into graphite without the use of a catalyst and fuels with high selectivity towards sustainable aviation fuel (SAF) is innovated. Heavy bio‐oil undergoes a conversion process similar to the commercial production of synthetic graphite including coking at 500 °C, calcination at 1000 °C, and graphitization at 2800 °C. The resulting biographite exhibits excellent performance in lithium‐ion battery configurations with specific capacity of ~330 mAh g −1 and a 96.8 % capacity rebound after high rate cycling. The liquid hydrocarbon co‐product from coking is suitable for hydrotreating into SAF. The aviation fuel fraction (70 wt % of the fuel produced) meets ASTM standards and is composed primarily of cycloalkanes (~80 wt %) which improves energy density compared to paraffins produced by other SAF pathways and may replace aromatics for elastomer swelling in traditional jet fuel with less soot production.
The potential of high entropy alloys (HEAs) to meet or exceed austenitic stainless-steel performance with the additional benefit of improved hot corrosion/oxidation resistance makes FCC HEAs attractive for use in energy applications. While shorter term creep tests have been reported in the literature on HEAs, not all methodologies utilize repeatable techniques. This manuscript reports on over 23,500 accumulated hours of tensile creep testing with adherence to ASTM standards on a melt solidified ingot of CoCrFeNiMn HEA converted to wrought plate using conventional thermo-mechanical processing techniques. The typical standard creep analyses are reported, i.e., Larson-Miller parameter, Monkman-Grant relationship, activation energy for creep, and creep stress exponents were calculated and compared to previously reported short-term creep tests. Additionally, characteristics of creep fracture and microstructural evolution are reported with cursory dislocation mechanisms investigated.
We report that current research shows that high-entropy alloys (HEAs) can offer superior oxidation resistance compared to more traditional austenitic stainless steels with equivalent tensile mechanical performance. While many reports have been published on creep of CoCrFeNiMn, few focus on the CoCrFeNi family of low to medium entropy alloys. In this manuscript, uniaxial tensile creep test results for more than 46,000 accumulated hours are presented on the equiatomic CoCrFeNi alloy. The alloy was manufactured at NETL using a vacuum induction melt solidification approach with a computationally designed homogenization cycle. After completing the homogenization cycle, the ingot was first hot forged and then hot rolled into 10 mm thick plate, a product form that is relevant to many industries. Creep tests were performed in the temperature range of 600-650 °C using applied stresses from 120 to 189 MPa. This study builds upon previous results on the CoCrFeNiMn family of high-entropy alloys and offers a modicum of clarification about performance compared to small button melts by using ASTM standard test procedures and mechanical test specimens. The apparent creep activation energy and creep stress exponent were similar to those for CoCrFe medium-entropy and CoCrFeNiMn high-entropy alloys. The post-test creep microstructure showed some Cr segregation, which has also been noted for other CoCrFe alloys. The CoCrFeNi alloy also presents a double minimum or two minimum creep rate phenomena.