Powder Materials for Energy Applications: Ceramic Powder Materials
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Powder Materials Committee
Program Organizers: Kathy Lu, University of Alabama Birmingham; Eugene Olevsky, San Diego State University; Somayeh Pasebani, Oregon State University; Hang Yu, Virginia Polytechnic Institute And State University
Wednesday 8:30 AM
February 26, 2020
Room: 17A
Location: San Diego Convention Ctr
Session Chair: Kathy Lu, Virginia Tech; Eugene Olevsky, San Diego State University
8:30 AM
Advanced Skutterudite-based Thermoelectric Unicouples by Near Net Shape Powder-based Fabrication for Future Space Power Applications: Michell Aranda1; Sutinee Sujittosakul1; George Nakatsukasa1; Vilupanur Ravi2; Ike Chi1; 1Jet Propulsion Laboratory (NASA/JPL); 2California State Polytechnic University, Pomona
Radioisotope Thermoelectric Generators (RTGs) have provided electrical power for various NASA missions to deep space since 1972. NASA’s Voyager 1 used RTGs and is now headed to Interstellar space after more than 40 years of exploration, the power system of this long mission is critical for Voyager’s success. RTGs use an assembly of thermoelectric unicouples connected electrically in series to convert heat into electricity. The production of these state-of-the-art SiGe-based thermoelectric unicouples was labor intensive and time consuming. Fabrication methods for those couples required complex steps that included powder co-hot pressing, component machining, grinding elements to geometric tolerance, and bonding subassemblies into a device. These time-consuming steps motivate the current development of a new processing approach, with the goal of reducing number of steps while retaining the properties and qualities of advanced Skutterudite-based thermoelectric unicouples. In this study, critical production steps; assembling, processing time and sintering conditions will be discussed.
8:50 AM Invited
Bulk Supercrystalline Nanocomposites with Enhanced Mechanical Properties for Multifunctional Applications: Diletta Giuntini1; Elisa Torresani2; Kyle Chan3; Lucien Saviot4; Büsra Bor1; Berta Domènech1; Malte Blankenburg5; Meir Shachar3; Martin Müller5; Eugene Olevsky2; Javier Garay3; Gerold Schneider1; 1Hamburg University of Technology; 2San Diego State University; 3University of California San Diego; 4Laboratoire Interciplinaire Carnot de Bourgnogne - Université de Bourgogne - Franche Comté; 5Helmholtz-Zentrum Geesthacht
Supercrystalline nanocomposites are a new category of particulate-based materials. They consist of inorganic nanoparticles functionalized with organic ligands and organized into periodic structures. Such nanoarchitectures are fostered for a wide range of applications, spanning through optoelectronics, plasmonics, batteries and solar cells. However, supercrystalline nanocomposites are typically produced in 2D or 3D micro-sized domains. This work presents a new processing routine, capable of yielding bulk macroscale supercrystalline materials. Such a routine is adaptable to a multiplicity of materials systems, and, together with upscaling, leads to a greatly enhanced combination of mechanical properties (modulus, hardness, strength and fracture toughness are increased 1-2 orders of magnitude). The mechanisms underlying such properties boost are identified and correlated to structure and processing parameters. Additionally, by applying this processing routine to an iron oxide-based system, the option of tuning the magnetic behavior of the nanocomposites is integrated, up to the development of a bulk superparamagnetic material.
9:20 AM
Cubic Sub-micron BiFeO3 Powders for Improved Electrical Properties: Jenna Metera1; Olivia Graeve1; 1University of California, San Diego
Ceramic capacitor technologies using lead based materials is being phased out for its environmental and handling hazards and bismuth ferrite is the next best replacement. Unfortunately, the electrical properties in bismuth systems are not as robust as the lead alternatives. The improvement of electrical properties such as charge density, charge anisotropy, relative permittivity, and dielectric loss are considered parameters that will make bismuth ferrite a competitive alternative. In order to maximize the utility of these properties, the answer is in the morphology of the powders and the contact points by which each particle is connected to another. The cubic particle morphology is produced through a hydrothermal synthesis with changes in the concentration of potassium hydroxide. The next step is to assemble the powders into a workable substrate for electrical testing. Powders have been characterized by X-ray diffraction and scanning electron microscopy.
9:40 AM Cancelled
Energy Concentration Joining of Nuclear-grade SiC/SiC Composites for Next Generation Nuclear Reactors: Geuntak Lee1; Shirley Chan1; Eugene Olevsky1; 1San Diego State University
The energy and cost-efficient joining technology of nuclear-grade-silicon carbide (SiC) fiber reinforced SiC matrix composites (SiC/SiC) is experimentally and theoretically demonstrated. Two types of SiC/SiC composites fabricated by chemical vapor infiltration (CVI) and nano-powder infiltration and transient eutectic-phase technique (NITE) are used for the joining experiments. The joined SiC/SiC plates are obtained by the Energy Concentration Joining (ECJ) technique which focuses the electric current and heat near the joining interface. The joining strength is measured by a single lap offset test. For comparison, α-SiC tubes, which have low electrical conductivity, are joined and tested by the torsion test. Also, the localized mechanical property is assessed by the nanoindentation for SiC/SiC and Vickers hardness test for α-SiC. Before and after joining the microstructure and crystal structure of the SiC/SiC components are measured by a scanning electron microscope (SEM) and X-ray diffraction (XRD).
10:00 AM Cancelled
As-sintered Long Porous Inconel 625 Tubes for Hot Gas Filtration for the Production of High-purity Silicon: Qiang Bing Wang1; Hui Ping Tang1; Ma Qian2; 1State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research; 2Royal Melbourne Institute of Technology
High efficiency filtration of hot (up to 400C) gas mixtures of SiHCl3 and HCl is an important step in the production of high-purity silicon for solar cells. This study reports the sintering fabrication of long porous Inconel 625 tubes (diameter: 54 mm; length: 1000 mm) and their commercial applications. Pre-alloyed Inconel 625 powder was used to fabricate such long porous Inconel 625 tubes, shaped by cold isostatic pressing and sintered in a hydrogen atmosphere. The as-sintered porous Inconel 625 tubes were characterised and tested. Then a cluster of 37 as-sintered porous Inconel 625 tubes with dimensions of 1000 mm in length and 54 mm in diameter were installed and used to filter gas mixtures of SiHCl3 and HCl at temperatures up to 400 C for 6 months. The products demonstrated outstanding performance.
10:30 AM Break
10:50 AM Invited
Synthesis, Sintering, and Electrochemical Properties of Lithium Conducting Garnets from Molten Salt Fluxes for All-Solid-State Lithium Batteries: Jon Weller1; Candace Chan1; 1Arizona State University
Lithium lanthanum zirconate (LLZO) garnet is a promising solid electrolyte for future lithium batteries owing to its high ionic conductivity, compatibility with metallic lithium, and thermal stability. Our recently established molten salt synthesis (MSS) to obtain LLZO nanoparticles has numerous advantages over conventional solid-state reaction. Molten salts present a large design space wherein the properties of the melt can be tuned to vary the properties of the LLZO. Further, modifying the basicity of the salt melt can substantially reduce the formation temperature of LLZO. However, the increased complexity of chemistry in molten salts requires fine tuning of both the molten salt medium and precursors to obtain pure phase LLZO materials with good ionic conductivity. The effect of salt composition on the product distribution and particle size and morphology will be discussed. Further, the sintering properties and ionic conductivity characteristics of powders made from MSS will be presented.
11:20 AM
Fabrication of Complex Shape Components by Spark-plasma Sintering Utilizing 3D-printed Controllable Interface: Elisa Torresani1; Charles Maniere2; Eugene Olevsky1; 1San Diego State University; 2Laboratoire CRISMAT
A challenging task of spark plasma sintering (SPS) technology is the production of complex shape components. This limitation of SPS is mainly related to the difficulty to obtain homogenous microstructures and uniformly distributed density in the final components. An original solution for these issues can be found in the application of the mobile evolving interface approach. However, this method introduces shape distortions in the final object due to the presence of different powders and of nonuniform relative density distribution in the initial pre-SPS powder volume.Therefore, a simulation tool that allows predicting the evolution of the controllable interface during SPS is required. A combined experimental and numerical study is conducted to investigate possible solutions of this problem. Two different methodologies to optimize the initial geometry of the controllable interface are developed. The first is based on the Dohelert experimental design and the second is based on the distortion inversion method.
11:40 AM
Superelastic Zirconia Powder for Shockwave Dissipation in Energy Infrastructure: Hunter Rauch1; Hang Yu1; 1Virginia Polytechnic Institute and State University
Structural materials lie at the base of modern energy infrastructure. Their design critically impacts the safety of power plants and power delivery services, especially during catastrophic events (earthquakes, explosions, etc.) where large dynamic loads can lead to spectacular failings. In this talk, we present a promising functional material that can protect our energy infrastructure from shockwave loads: superelastic cerium stabilized zirconia powder. This powdered ceramic has a tunable and reversible martensitic phase transformation, which is associated with a large hysteresis loop that allows it to dissipate substantial kinetic energy as heat. In this talk, an overview of the extrinsic effects of particle size and polycrystallinity on the phase transformation are discussed, including results from in situ neutron scattering experiments, DSC, XRD, and SEM. We show a broad, continuous regime of functionality, which is unique to the granular form. Future applications of doped zirconia in other forms are also presented.