Glass under shock loading: Novel measurements at National Laboratory facilities.
Abstract
GLASS UNDER SHOCK LOADING:NOVEL MEASUREMENTS AT NATIONAL LABORATORY FACILITIESAbstractStatement of WorkWe will conduct measur"ements of shocked glass at national laboratory facilities that offer pulsed x-rays for time-resolved x-ray diffraction, scattering," and imaging measurements and that offer high-power lasers for shock generation under conditions that are complementary to those we can achieve in our own shock generation system at MIT. Samples will be fabricated to enable shock loading of silica glass that will be monitored using x-rays and using a homebuilt femtosecond stimulated Raman scattering (FSRS) system. Powder samples provided by ONR will also bemeasured using FSRS and x-ray diffraction (XRD).Objectives We aim to make measurements of shocked glass samples that are complementary to those we carryout at MIT using our tabletop laser system whose output is split for shock generation and fo"r monitoring of the shocked samples through optical imaging and FSRS. In one class of complementary measurements, we will use pulsed"" x-ray sources for time-resolved XRD andscattering. In another, we will use high-power laser sources to generate shock conditions ("includingpressure and duration) that differ from those that we reach at MIT.ApproachWe will use methods we have developed for la"ser generation of shock waves that propagate in the plane of a thin sample, perpendicular to the direction of the laser light. In th""is manner the shock wave and the shocked sample are directly accessible to probing by additional laser light or by xrays, with both" spatial and temporal resolution that allow us to monitor the lateral propagation of the shock wave and the localized time-dependent sample responses induced by the shock. We will interface our shock generation apparatus with pulsed x-ray sources at national labor"atory facilitiesin order to measure time-resolved x-ray diffraction, which will reveal shock-induced crystallinity and phase transi""tions, and x-ray scattering and imaging, which may reveal the length scales of induced structural features. At high-power laser faci""lities, we will generate shocks that may reach higher pressures, longer durations, and different shear/compressional characteristics" than those we generate with our system at MIT. We will use femtosecond stimulated Raman scattering (FSRS)for time-resolved vibrational spectroscopy of shocked samples which may reveal lattice vibrationsthat indicate the formation of SiO2 crystalline phases and" bonding geometries. Future Naval RelevanceThe research will advance our understanding of shocked glass, yielding insights that w"ill be relevant to the development of materials with improved shock dissipation and resistance. The research will also advance our c"apabilities for characterization of shocked materials, relevant to Navy interests in a wide range of protective materials and energe"tic materials.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 01, 2017
- Source ID
- N000141712706
Entities
People
- Keith A. Nelson
Organizations
- Massachusetts Institute of Technology
- Office of Naval Research
- United States Navy