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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,621 records · Page 90
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

The Development of High Temperature Thermoplastic Composite Materials for Additive Manufactured Autoclave Tooling

In this work, ORNL and Techmer investigated and screened different high temperature thermoplastic reinforced materials to fabricate composite molds for autoclave processes using Additive Manufacturing (AM) techniques. This project directly led to the development and commercial release of two printable, high temperature composite materials available through Techmer PM. These new materials are targeted for high temperature tooling made via large scale additive manufacturing.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Additive Manufacturing of Molds for Fabrication of Insulated Concrete Block

Oak Ridge National Laboratory (ORNL) worked with concrete block manufacturer, NRG Insulated Block, to demonstrate additive manufacturing of a multi-component block mold for its line of insulated blocks. Solid models of the mold parts were constructed from existing two-dimensional drawings, and the parts were fabricated on a Stratasys Fortus 900 using ULTEM™ 9085. Block mold parts were delivered to NRG and installed on one of their fabrication lines. While form and fit were acceptable, the blocks made from the molds collapsed when extruded from the printed molds during NRG’s testing. However, the project demonstrated significant time and cost reductions and achieving proper functionality through the use of different additive manufacturing techniques.

42 ENGINEERING↗
DOE OSTI2018

Hybrid Ionic-Nano-Additives for Engine Lubrication to Improve Fuel Efficiency

We developed a new class of hybrid organic-inorganic/metallic nanoparticles (NPs) as additives for polyalphaolefin (PAO) for friction and wear reduction to improve engine energy efficiency. The hybrid additives were synthesized by using polymers, ionic liquid (IL)-containing polymers, organic ligands, or ILs to functionalize NPs. The tribological properties of these hybrid NPs or mixtures of NPs and ILs were studied by high contact stress ball-on-flat reciprocating sliding tests at 100°C. Significant reductions in friction and wear were achieved compared to PAO base oil. The lubrication mechanisms were elucidated by both experimental and simulation studies.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Feasibility of Using Additive Manufacturing to Produce Automotive Tooling

Oak Ridge National Laboratory’s (ORNL) Manufacturing Demonstration Facility (MDF) worked with Diversified Tooling Group (DTG) in phase I of this technical collaboration to determine the feasibility of using additive manufacturing to produce automotive tooling using polymer Big Area Additive Manufacturing (BAAM) systems and will potentially work with DTG in phase II on metal BAAM systems. The following phase I goals in polymer BAAM were met: a polymer sheet metal check fixture and a polymer foundry casting pattern were completed and shipped to DTG.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Benchscale Evaluation of Nanodiamond Oil Additives

This CRADA between Cool-X and ORNL was to investigate the impact of diamond nanoparticles as diesel engine oil additives on lubricating behavior and gain fundamental understanding of the friction and wear reduction mechanisms. Systematic tribological bench tests were used for evaluating the Cool-X diamond nanoparticles (ND) as candidate diesel engine oil additives, and surface characterization was carried out to reveal the friction reduction mechanisms. No significant micro-rolling effect or increased oil pressure-viscosity coefficient was observed. Instead, a faster running-in and moderate friction reduction were achieved by the ND in tests of used diesel engine components, which was attributed to the polishing effect. ND agglomeration seemed to a problem and could significantly impair the functionality and future research is needed to seek the mitigation.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2018

Tensile and Microstructure Characterization of SNS Target Swirl Bubblers Fabricated by Additive Manufacturing

During operation the mercury facing surfaces of the Spallation Neutron Source target vessel are damaged by cavitation-induced erosion. One option to decrease the erosion damage to the SNS target vessel surfaces is to decrease the intensity of the pressure waves using small bubble mitigation. Injection of small diameter helium bubbles into mercury has been shown in decrease the intensity of proton-induced pressure waves and mitigate erosion damage to mercury/container interface surfaces. Several bubbler designs have been evaluated for implementation in the SNS target. One promising bubbler design is called a swirl bubbler, which is capable of producing a high density of very small diameter helium bubbles in flowing mercury. Due to the complexity of the swirl bubbler design and the geometric restrictions of conventional machining processes, additive manufacturing was considered for fabrication. But there was uncertainty with the mechanical properties of bubblers fabricated with additive manufacturing. A series of experiments were designed to characterize the tensile properties and microstructure of swirl bubblers fabricated using selective laser melting (SLM), both before and after consolidation via hot isostatic pressing (HIPing). This report summarizes the tensile and microstructural characterization of HIPed and non-HIPed swirl bubblers produced via the SLM process. The results show that the as-fabricated material contained appreciable porosity, lack-of-fusion defects, and inconsistent tensile properties with essentially zero ductility. But after a HIPing treatment the microstructure became fully consolidated, and the tensile properties surpassed the requirements specified in the material standard for steel-mill produced 316L plate material used to fabricate the SNS target vessel. While further testing is recommended to evaluate the material’s susceptibility to fatigue fracture, these results indicate 316L bubbler assemblies produced SLM and HIPed are promising candidates for implementation in a future SNS target module.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Additive Manufacturing Using Epoxy and Anhydride Curatives

ORNL worked with Dixie Chemical Company to develop epoxy material solutions with anhydride curatives printable on a large-scale printer. Rheological evaluation showed that the addition of high surface area fillers produced a stable yield-stress fluid that is capable of being used in extrusion deposition additive manufacturing. The resulting printed structures have the necessary mechanical and thermomechanical performance to be used in elevated temperature tooling for various composites processing, such as an autoclave.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Evaluation of Radiation Proofing Polyethylene: Use of Oxygen Scavenging Additives

The degradation of polyethylene (PE) from radiation sources with both thermal and nuclear interactions show sensitivities towards oxygen and air. Characterization of the sensitivities in both inert and oxygenated atmospheres can be characterized by thermogravimetric analysis (TGA). Under argon, the thermal degradation of PE follows a random scission pathway that has activation energy of ~229 kJ mol -1 . The activation energy of PE is reduced by ~30% when 1% air is added to the inert argon atmosphere, illustrating the impact of oxygen on the degradation of PE. This effort seeks to diminish degradation of PE waste containment bags and extend their lifetime, thereby, reducing the cost and worker exposure risk. The project evaluated the use of oxygen scavenger nanoparticles to mitigate the deteriorating effects of oxygen on polymer physical properties and reduce polymer degradation. The thermal degradation of PE composites with various additives were tested and two additives showed promising results approaching the activation energy of pristine PE in an inert atmosphere. This activity was sponsored by the EM Office of Technology Development through SRNL’s Technical Task Plan SR091701.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Additive Manufacturing of Polyurethane Foam Mold Tooling

In this DOE AMO Technical Collaboration (MDF-TC-2017-078), ORNL partnered with Whirlpool Corporation. to develop low-cost prototype tooling for the manufacturing of refrigerators. Techniques for producing watertight and high thermal-conductivity tools were developed and evaluated. In addition, additive manufacturing systems at multiple volume and resolution scales were evaluated for performance, resolution, and cost for the intended application.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Conceptual Design for a Mobile Adaptive Additive Manufacturing In-situ Diagnostic End-Station (MAdAM)

With the importance of additive manufacturing (AM) growing, researchers are interested in characterizing the dynamics of metal solidification in AM processes and its impact on part structure and performance. In-situ AM experiments at Xray facilities allow for the temporal study of these systems but require many different connections, interfaces, and equipment which can take a considerable amount of time and effort to set up, reducing the user’s useful beamtime. It is essential to provide the means for an experiment to achieve the relevant thermal boundary conditions and control the cooling rates to replicate the conditions of the manufacturing process. A team effort defined the overall capabilities and requirements for a mobile adaptive additive manufacturing (MAdAM) in-situ diagnostic end-station that can be used at X-ray facilities. Further, specific details of the key elements of the system are developed. Further iteration and development of details will be needed; the path forward and next steps for such a project is described.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Considerations for Application of Additive Manufacturing to Nuclear Reactor Core Components

The following chapter represents the current state of literature on the selected additive manufacturing technologies and was written with an emphasis on quality control and material performance repeatability. Research and standards published by government entities such as the National Institute of Standards and Technology (NIST) and Department of Energy (DOE) have been included where applicable. It is recommended that literature be reviewed, and new knowledge integrated no less frequently than every four years due to the rapid pace of advancements in additive manufacturing and associated industries. AM presents unique challenges in certification for NPP applications such as anisotropic material properties, porosity, underdeveloped process control feedback systems, and reproducibility. This chapter begins with an overview of the selected AM technologies, followed by a systematic review of literature to detail the fabrication process and difficulties with repeatably fabricating fully dense, geometrically accurate components with known material properties.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Recommendations for DOT 7A Type A Drum Closure and Drop Testing with Additional 49 CFR 173.465(c)(2) Testing and Analysis

The Savannah River National Laboratory (SRNL) is in the process of developing recommendation for the U S. Department of Energy contractors and vendors who want to qualify drums as U S. Department of Transportation (DOT) 7A Type A to meet 49 CFR 173.465 drop testing requirements for fissile and non-ftssile material to maintain containment. Based on the finite element analysis (FEA) models, the safety features suffering the maximum damage that result in loss of containment are identified as the closure ring mechanism (in entirety), the top (mouth area) of the drum, and the lid (including the gasket). The maximum damage is measured in terms of the collective ability of these combined three safety features to maintain containment. As such, both drop testing and FEA were performed to determine the sensitivities of these safety features to drop variations. As part of this effort, a series of physical drop tests and FEAs were conducted at SRNL. These tests used Skolnik drums, CQ5508L (see Attachment 1), which are open DOT 7A Type A open- head carbon steel 208-liter (55-gallon) drums with 12-gauge bolted closure rings. Variables studied were (1) stress relief methods during closure ring installation, (2) content configurations, and (3) drum orientations during a 4-foot free fall. It should be noted that the Skolnik CQ5508L drums have a closure ring with a "V shaped" cross section. (1) The closure testing with analysis confirmed that closure stress relief by rapping is necessary to distribute the closure ring tension around the perimeter and to maintain sufficient closure pre-load for lid retention during 4-foot drops of the heavier packages (500 to 1,000 lbs). It was concluded that no specific style of stress relief is preferred (e g., multi-step rapping/torqueing process, heavy hits vs. light hits, hitting near closure vs. away), as long as no additional change in bolt torque occurs with additional rapping. (2) (3) Modeling indicated that maximum damage is a result of both: (2) content configuration and (3) drop orientation. The worst-case content configuration is one with an eccentrically loaded concentrated content mass. FEA modeling showed that the center- of-gravity over top (CGoT) with the eccentric content on the high side was the orientation of maximum damage relative to drum lid retention. In this content configuration (i.e., CGoT), FEA modeling showed payloads over 500 lbs were required to contain a load distribution plate between content and lid. Both analysis and testing showed the drum with distribution plate can pass the 4-foot CGoT drop.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Screening of Additional Candidate Low-Temperature Glasses for Technetium Recovered from Hanford Effluent Management Facility Evaporator Bottoms

In this annex to a previously reported study, a series of laboratory screening tests was conducted to identify low-temperature glasses that have significant potential for use in disposition of technetium from a Hanford Tank Waste Treatment & Immobilization Plant (WTP) secondary liquid waste stream. Specifically, a glass waste form is sought that would be suitable for on-site disposition of technetium, salts, and other species in a Tc-rich stream recovered by ion exchange from the future Effluent Management Facility (EMF) evaporator concentrate. In the current study, several additional candidate glasses were identified, and testing of previous candidates was extended to include the Toxicity Characteristic Leaching Procedure (TCLP). In non-radioactive testing with rhenium surrogate, new formulations incorporated a simulated ion exchange eluate at temperatures below 750 °C to produce an amorphous, or mixed crystalline-amorphous, product. Incorporation of technetium (NaTcO 4 )-containing simulated eluate was evaluated for two of these glasses. Technetium was not retained well in these glasses, confounding the previous conclusion that Tc volatilization during vitrification can be reduced by appropriate selection of low-temperature glasses. Preliminary data for additional low-temperature glass compositions and recommendations for future work are provided. This report is a deliverable associated with requisition 55068-004-03 NFE-17-0020 "Candidate Low-T Glass Waste Forms for EMF Bottoms On-Site Disposition Alternative."

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Characterization of vacuum conductance in commercially available (sintered) and additively manufactured porous structures

This report documents the work performed in characterizing the vacuum conductance of porous structures made by conventional sintering (purchased as commercially available products from Mott Corporation ranging from 20 to 100 media grade) and additive manufacturing (powder bed fusion). The additively manufactured structures described in this report were originally intended to be the first iteration of several in an effort to produce desirable conductance characteristics. While resources were not available to link the experimental results to a modeling effort to better understand why certain characteristics were observed, the author hopes that this report may provide a useful set of data for future use, especially as sintered porous structures are not uncommonly procured from Mott corporation for research and development purposes. For that reason, all of the raw data is tabulated in the Appendix: it is possible to reproduce all of the figures shown in this report independently. For a quick order-of magnitude scan of the conductances, refer to Figures 5, 6, 8 and 9.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Additive Manufacturing Fabrication of PEEK Counter-Current Centrifugal Contactor Components

Additive manufacturing (AM, also known as 3D printing) offers significant advantages for the fabrication of annular centrifugal contactor-separator (CCS) stages, particularly when complemented by post-processing via traditional machining. The shortcomings of 3D printing of CCSs are offset by its low cost, quick turnaround, and ability to manufacture enhanced mixing sections and multistage modules. High-density acrylic materials show promise for improved chemical resistance and mechanical properties. The demonstration of the MOEX process using acrylic AM CCS stages confirmed their full functionality and showed significant flexibility in geometry design while using relatively low-cost plastic materials. Over the past two years, AM has been used to produce low-cost centrifugal contactor components, ranging from bench-scale laboratory testing to a full-scale industrial process with on-hand availability of spare parts and great flexibility in design modifications and quick testing and implementation. However, the shortcomings of stereo lithography assembly (SLA)-printed acrylic components became apparent rather quickly. By the completion of the initial MOEX demonstration using the 9-stage 2-cm CCS bank, nearly half of the rotors had begun to fail from pitting and cracking. These problems were most likely caused by swelling of the rotor due to liquid absorption, resulting in improper excess run out, mechanical abrasion, and chemical exposure of the roughened surface. Additional deterioration of the acrylic stages was later discovered when the interiors of the acrylic housings began to experience flaking and delamination as the plastic dried out several weeks after the tests. All of these issues caused severe limitations to the lifespan of the CCS stages, which are acceptable for R&D but undesirable for commercial-scale production.

42 ENGINEERING↗
DOE OSTI2020

Additive Manufacturing Interface Profiles for Jet Studies on the Vertical Shock Tube

Understanding the mixing between two fluids of disparate densities (i.e., variable density mixing) is important for the lab's mission. Experiments are required to validate our codes, such as RAGE, FLAG, and the BHR mix model. The role initial conditions (ICs) have on instability growth and the transition to turbulence is not completely understood and comparisons with experiments are needed. The Extreme Fluids team focuses on experiments at Los Alamos that utilize gases and low shock velocities (Mach <2 in air). These experiments have the advantage of high fidelity diagnostics capable of temporally and spatially resolved velocity and density measurements. One main difficulty is setting up a specific interface profile between the two gases. While attempts have been made to do so without the aid of a solid structure (i.e., a membrane), the results are limited in the range of possible shapes and reproducibility. Membranes provide the best way to provide a deterministic initial condition. However, fragments from the membrane can interfere with the flow and instability growth, as well as the diagnostics. In this project, we focused on exploring the materials and techniques available via modern additive manufacturing (i.e., 3D printing) to test if they could address some of the shortcomings of prior membrane designs. Our goal was to find a material that would have minimal impact on our experiment while also providing us with a means to produce complex initial conditions. This report details our work to explore the range of additive manufacturing capabilities and the jet-like structures we were able to generate using three-dimensional initial conditions.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Commercialization of Big Area Additive Manufacturing (CRADA NFE-16-06083 Final Report)

Oak Ridge National Laboratory (ORNL) first partnered with Cincinnati Incorporated (CI) through a Cooperative Research and Development Agreement (CRADA) (NFE-14-04957) in 2014 to demonstrate the feasibility and viability of Big Area Additive Manufacturing (BAAM). The first CRADA was a success and paved the way for large format additive manufacturing (LFAM). ORNL and CI partnered again for this second CRADA (NFE-16-06083) to improve process control, enhance printing capabilities, and shift towards production capability.

42 ENGINEERING↗
DOE OSTI2019

Additively Manufactured Photovoltaic Inverter (AMPVI)

Successful integration of hundreds of gigawatts of solar photovoltaics (PV) into the electric power system requires transformative power conversion system design that optimizes various trade-offs among conflicting objectives, such as performance, reliability, functionality, and cost. To address this need, National Renewable Energy Laboratory, Oak Ridge National Laboratory, and Purdue University teamed up to develop a unique PV inverter design. The Additively Manufactured Photovoltaic Inverter (AMPVI) combines newer wide bandgap high-voltage silicon carbide (SiC) semiconductor devices with revolutionary concepts such as additive manufacturing and multi-objective magnetic design optimization. The AMPVI will not only provide superior technical capabilities in terms of energy conversion but also mitigate market barriers for SiC-based PV inverters. The benefits for this design will include better utilization of PV power due to higher DC voltage, lower operations and maintenance costs, better system efficiency, longer system lifetime, and advanced grid support functionalities for easier grid integration. All these advantages will lead to a significant reduction of the levelized cost of energy for PV systems. Activities in Budget Period 1 (BP1) of this 3-year integrated project were focused on development and component-level validation of the foundational building blocks needed for the AMPVI. Multiple interrelated tasks were completed in parallel during work towards the initial development of the high-voltage SiC-based power block, gate driver, controller board, and control algorithms. Initial development of magnetic design tools and initial inverter thermal and mechanical design was also completed in this period. All these activities ensured that the initial prototype (called “alpha-prototype”) power block and controller would be ready after BP1 for integration into the first inverter prototype (i.e., the alpha-prototype inverter) in BP2.

14 SOLAR ENERGY↗