Ultra-high-speed studies of shock phenomena in a miniaturized system: A preliminary evaluation

Abstract

Sandia is a rnultiprograrn laboratory operated by Sandia Corporation, a Lockheed Martin Company, for t h e United S t a t e s Department of Energy under Contract DE-AC04-94AL85000.Approved for public release; distribution is unlimited.(rtrl Sandia National Laboratories SF AbstractA laboratory-scale experimental test system for small-scale studies of shock phenomena has been assembled. This system uses a variety of miniature test platforms in which shock loading is provided by laser-driven flyer impact. Acceptor materials include thin-film explosives and high-density metal foils. Optical access is provided for high-speed optical diagnostics such as optically recording velocity interferometry and single-pulse Raman spectroscopy. The experimental assembly for Raman studies features a common laser source for both flyer generation and excitation of Raman scattering (to achieve high timing precision) and a detection scheme that uses the coupling fiber for the excitation source to collect w i t h high efficiency backscattered Raman light. Preliminary system evaluation experiments indicate that detailed particle velocity studies of the dynamic material properties of high-density metals under short-pulse, high-strain-rate loading can be performed in a miniaturized test configuration. Single-pulse Raman studies on shock compressed thin film explosives also appear feasible if the thickness and grain structure of these films can be tailored to enhance the Raman scattering signal sufficiently. Possible improvements in the experimental design and a number of likely applications of these techniques are also discussed.3

Characteristics of Step-Shaped Laser-Driven Flyers on Fiber End Face Based on a Ti/Al Ablation Layer

“…Laser pulse ablated the Al film with a thickness of about 10 μm on the fiber end face to achieve a peak flyer velocity of 3 km/s. 17 For a large core diameter multimode fiber, Zhao employed a 1.0 mm core diameter multimode fiber with an LDF structure of Al/Al 2 O 3 /Al and total LDF thickness of 5.5 μm. The flyer velocity reached 1.5 km/s under the condition of 40 mJ laser energy at the output face of the fiber.…”

Investigating Shock Compression Phenomenon using Laser-Driven Micro Flyer Plates at DEVCOM Army Research Laboratory

“…The interrogation of controlled, reproducible, and well-characterized shock fronts is crucial to studying these responses. 1 Laserdriven flyer plates can be used to produce such shock fronts on a laboratory benchtop with high experimental throughput. [2][3][4][5][6][7] In this work, we build on a previous iteration of a benchtop, laser-driven flyer plate system developed at ARL, to achieve higher launch velocities with larger flyer plates.…”

Influence of Laser Beam Profiles on the Performance of Laser‐Driven Flyers

“…The la-ser power should be delivered by an optical fiber to assure the precision, reliability and convenience [15,16]. To this end, Trott [17,18] managed to transmit a 30 mJ pulsed laser with a pulse duration of 25 ns through a 0.4 mm diameter optical fiber rather than lens coupling, and the velocity of 12.7 μm thick Al flyers reached up to 2.3 km/s. Zhao [19] developed a flyer launching system with an optical fiber delivering subsystem.…”