Shock initiation of explosives: High temperature hot spots explained
Abstract
We investigated the shock initiation of energetic materials with a tabletop apparatus that uses km s−1 laser-driven flyer plates to initiate tiny explosive charges and obtains complete temperature histories with a high dynamic range. By comparing various microstructured formulations, including a pentaerythritol tetranitrate (PETN) based plastic explosive (PBX) denoted XTX-8003, we determined that micron-scale pores were needed to create high hot spot temperatures. In charges where micropores (i.e., micron-sized pores) were present, a hot spot temperature of 6000 K was observed; when the micropores were pre-compressed to nm scale, however, the hot spot temperature dropped to ∼4000 K. By comparing XTX-8003 with an analog that replaced PETN by nonvolatile silica, we showed that the high temperatures require gas in the pores, that the high temperatures were created by adiabatic gas compression, and that the temperatures observed can be controlled by the choice of ambient gases. The hot spots persist in shock-compressed PBXs even in vacuum because the initially empty pores became filled with gas created in-situ by shock-induced chemical decomposition.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 07, 2017
- Source ID
- 10.1063/1.4985593
Entities
People
- Belinda P. Johnson
- Dana D. Dlott
- Kenneth S. Suslick
- Nitin K. Neelakantan
- Will P. Bassett
Organizations
- Air Force Office of Scientific Research
- Army Research Office
- Defense Threat Reduction Agency
- University of Illinois Urbana–Champaign