Bulletin of the American Physical Society
20th Biennial Conference of the APS Topical Group on Shock Compression of Condensed Matter
Volume 62, Number 9
Sunday–Friday, July 9–14, 2017; St. Louis, Missouri
Session Y6: Equation of State VII |
Hide Abstracts |
Chair: Rick Kraus, Lawrence Livermore National Laboratory Room: Regency Ballroom E |
Friday, July 14, 2017 9:15AM - 9:30AM |
Y6.00001: High-Pressure Ramp EOS Measurements on the NIF Dayne Fratanduono, Suzanne Ali, Tom Arsenlis, David Braun, Angela Cook, Jon Eggert, Jim McNaney, Amalia Fernandez Panella, Damian Swift, Ray Smith Ramp compression experiments have opened a path toward the measurement of extreme states of compression for solid-state materials on lasers, pulsed power, and gas guns.~ The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory offers a unique capability to study solid-state materials under these extreme conditions.~ Using the NIF facility, we have recently made great advancements measuring the isentrope many materials. The ramp compression experiments on the NIF have demonstrated the ability to accurately measure the stress-density response of metals (Fe, Al, Cu and Pt) and insulators (LiF) to pressures in excess of 8 Mbar. I will present the recent advancements~ in the pursuit of understanding the EOS of warm dense matter and close with future plans for HED EOS experiments on the NIF. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. [Preview Abstract] |
Friday, July 14, 2017 9:30AM - 9:45AM |
Y6.00002: Radiance Measurement on Shock-Ramp Loaded Tin Jeffrey Nguyen, Minta Akin, Paul Asimow, Neil Holmes An accurate material temperature is not only an essential component of an equation of state, but also a good measure of a phase transition, its kinetics, and associated thermal transport properties. In a series of experiments, we measured particle velocity and thermal emission at the tin-LiF interfaces on shock and ramp loading experiments. Using a graded density impactor, we drive the tin sample through melting with the initial shock and then further ramp-compress it back into the solid phase. Various configurations of experimental set-up were used to simultaneously measure particle velocity and thermal emission from which we deduce pressure, density, sound velocity and temperature. A gray body radiation is assumed in these calculations. We present here more recent results and updated analysis of shock-and-ramp-loaded tin experiments. The measured particle velocity shows a traditional signature for phase transition, while thermal radiance exhibits a change consistent with the heat of solidification. We will discuss here the mechanical and thermal aspects of this phase transition, its kinetics, and thermal transport issues in this experiment. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. [Preview Abstract] |
Friday, July 14, 2017 9:45AM - 10:00AM |
Y6.00003: Quasi-Isentropic Compression of Wrought and Additively Manufactures 304L Stainless Steel Paul Specht, Justin Brown, Jack Wise, Michael Furnish, David Adams The thermodynamic and constitutive responses of both additively manufactured (AM) and traditional wrought processed 304L stainless steel (SS) were investigated through quasi-isentropic compression to peak stresses near 1Mbar using Sandia National Laboratories' Z machine. The AM 304L SS samples were made with a laser engineered net shaping (LENS\texttrademark) technique. Compared to traditional wrought processed 304L SS, the AM samples were highly textured with larger grain sizes (\textit{i.e.\ }near 1mm) and residual stresses ($>$ 100 MPa). Interferometric measurements of interface velocities enabled inference of the quasi-isentropes for each fabrication type of 304L SS. Release from peak stress provided flow strength measurements of the wrought and AM 304L SS. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000. Approved For Unclassified Unlimited Release SAND2017-2040A. [Preview Abstract] |
Friday, July 14, 2017 10:00AM - 10:15AM |
Y6.00004: Non-iterative determination of the stress-density relation from ramp wave data through a window Evan Dowling, Dayne Fratanduono, Damian Swift In the canonical ramp compression experiment, a smoothly-increasing load is applied the surface of the sample, and the particle velocity history is measured at interfaces two or more different distances into the sample. The velocity histories are used to deduce a stress-density relation by correcting for perturbations caused by reflected release waves, usually via the iterative Lagrangian analysis technique of Rothman and Maw. We previously described a non-iterative (recursive) method of analysis, which was more stable and orders of magnitude faster than iteration, but was subject to the limitation that the free surface velocity had to be sampled at uniform intervals. We have now developed more general recursive algorithms suitable for analyzing ramp data through a finite-impedance window. Free surfaces can be treated seamlessly, and the need for uniform velocity sampling has been removed. These calculations require interpolation of partially-released states using the partially-constructed isentrope, making them slower than the previous free-surface scheme, but they are still much faster than iterative analysis. [Preview Abstract] |
Friday, July 14, 2017 10:15AM - 10:30AM |
Y6.00005: An iterative forward analysis technique to determine the equation of state of dynamically compressed materials Suzanne Ali, Richard Kraus, Dayne Fratanduono, Damian Swift, Jon Eggert We developed an iterative forward analysis (IFA) technique with the ability to use hydrocode simulations as a fitting function for analysis of dynamic compression experiments. Current single experiment analysis techniques are frequently unable to decouple contributions to the measured material response. The IFA method enables global analysis of data from varied experimental platforms and time scales by optimizing over model parameters in the simulations, breaking the degeneracy in the material response. As validation, we simultaneously analyzed multiple magnetically driven ramp compression experiments on copper and compared with the conventional technique of analytically averaging results from Lagrangian analysis. Uncertainty propagation from the experimental uncertainties to the final stress-strain path was accomplished using both Monte Carlo and perturbation methods. Excellent agreement is obtained for both the material properties and the uncertainties. [Preview Abstract] |
Friday, July 14, 2017 10:30AM - 10:45AM |
Y6.00006: Experiences in Automated Calibration of a Nickel Equation of State John H. Carpenter Wide availability of large computers has led to increasing incorporation of computational data, such as from density functional theory molecular dynamics, in the development of equation of state (EOS) models. Once a grid of computational data is available, it is usually left to an expert modeler to model the EOS using traditional techniques. One can envision the possibility of using the increasing computing resources to perform black-box calibration of EOS models, with the goal of reducing the workload on the modeler or enabling non-experts to generate good EOSs with such a tool. Progress towards building such a black-box calibration tool will be explored in the context of developing a new, wide-range EOS for nickel. While some details of the model and data will be shared, the focus will be on what was learned by automatically calibrating the model in a black-box method. Model choices and ensuring physicality will also be discussed. \\ \\ {*}Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700