April 5, 2022 @ 3:00 pm - 4:00 pm
Please contact Veronica Turner for connection information.
Detonation testing of potential new energetic materials being developed by the military is costly and time-consuming, so novel laboratory-scale methods are needed to evaluate new materials prior to scale-up for detonation tests. In our laboratory, a pulsed laser is used to initiate the chemical reactions that occur during a detonation event. A focused, nanosecond-pulsed laser with sufficient energy to exceed the breakdown threshold of a material generates a laser-induced plasma with high temperatures (>10,000 K), pressures (tens of GPa), and shock velocities (multiple km/s). The subsequent chemical reactions, shock wave expansion, and deflagration reactions of laser excited energetic materials are monitored using emission spectroscopy and high-speed cameras using a technique called laser-induced air shock from energetic materials (LASEM). Example applications and recent improvements to the LASEM technique will be presented. New methods for determining the electrostatic sensitivity of novel reactive materials using an order of magnitude less material than conventional testing will also be discussed.
Dr. Gottfried obtained a Ph.D. in Physical Chemistry from the University of Chicago in August 2005, receiving numerous fellowships and awards for excellence in academics and research, including a National Science Foundation Graduate Fellowship and the William Rainey Harper Dissertation Fellowship. She joined the US Army Research Laboratory (ARL) in September 2005 as a postdoctoral fellow and was hired in May 2008. Dr. Gottfried recently received a Department of the Army Civilian Service Commendation Medal for outstanding technical excellence. Dr. Gottfried has written four book chapters and has more than 60 peer-reviewed papers, including four invited reviews and four featured cover articles. She has also published more than 90 ARL technical reports. She has been an invited speaker at 18 international conferences and taught short courses on laser-induced breakdown spectroscopy and chemometric analysis. Dr. Gottfried’s current work is focused on laser spectroscopy of energetic materials for laboratory-scale characterization, model validation, and a fundamental understanding of reaction mechanisms during explosive initiation.