Thermal decomposition reactions of HMX and RDX and their importance in predicting cookoff hazards
- Sandia National Labs., Livermore, CA (United States)
- Army Research and Development Command, Dover, NJ (United States)
To develop robust models for predicting the response of munitions under abnormal conditions associated with cookoff, it is necessary to be able to accurately characterize the following: the time to ignition, the location of the ignition point within the munition, and the combustive behavior of the damaged energetic material after ignition. For, the response of the munition, as controlled by these parameters, will determine whether its response will be characterized by a relatively mild deflagration or whether it will be characterized by a more damaging detonation. Several of the underlying properties of the energetic materials used in munitions that must be understood in order to accurately characterize these parameters are the chemical and physical changes that occur in these energetic materials as they are heated. The chemical changes involve overcoming the forces that tend to stabilize these materials, such as binding within the crystal lattice or intermolecular hydrogen bonding, and their transformation to less stable forms, such as mixtures of gases with high energy content. The physical changes typically involve phase changes of the material. One significant phase change is the slow transformation of the energetic materials from the solid reactant to gas phase products. This transformation can lead initially to the formation of high pressure gas bubbles within the solid particles and ultimately to changes in the porosity and gas permeability of the energetic material formulation. The presence of these reactive gases within high pressure bubbles can lead to increased hot spot formation of the material if it is compressed. The increased porosity can lead to significant increases in the burn rates of these materials at high pressures.
- Research Organization:
- Sandia National Labs., Livermore, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States); Department of Defense, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 10151192
- Report Number(s):
- SAND-94-1191C; CONF-9405136-11; ON: DE94011430; BR: GB0103012
- Resource Relation:
- Conference: 1994 joint USA-Russia energetic material technology symposium,Livermore, CA (United States),18-25 May 1994; Other Information: DN: Includes vugraphs; PBD: [1994]
- Country of Publication:
- United States
- Language:
- English
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