<p>The transformation of mechanical
energy into thermal energy within composite energetic materials through various
thermomechanical mechanisms is thought to lead to the creation of localized
areas of intense heating. The growth of these “hot spots” is responsible for
the bulk reaction or decomposition of the energetic material. Understanding the
formation and growth of these hot spots has been an active area of research
particularly for high-speed impact and shock conditions, but further work
remains to be done in particular with respect to hot spot formation due to
periodic mechanical excitation. Previous literature has established that many
potential thermomechanical mechanisms may act at the interface between the constituent
components of a composite energetic material. In order to provide further
insight and guidance into the design of safer and more resilient energetic
materials, the role of adhesion on hot spot formation for polymer bonded
explosives (PBXs), a subset of composite energetic materials, was explored.
Single HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane) crystals in polymer blocks
were subjected to ultrasonic excitation and subsequent heating was captured via
infrared thermography. Subsequent testing of HMX PBXs using a drop weight tower
captured changes in the sensitivity of the energetic material. Variation of the
polymer binder allowed for a range of adhesive and mechanical properties to be
examined. These experiments on the role of adhesion under these kinds of
excitations provided insight into how mechanical energy is being transformed
into localized heating.</p>
| Identifer | oai:union.ndltd.org:purdue.edu/oai:figshare.com:article/14374061 |
| Date | 30 April 2021 |
| Creators | Jason A Wickham (10526450) |
| Source Sets | Purdue University |
| Detected Language | English |
| Type | Text, Thesis |
| Rights | CC BY 4.0 |
| Relation | https://figshare.com/articles/thesis/The_Role_of_Adhesion_and_Elastic_Modulus_on_the_Sensitivity_of_Energetic_Materials_to_Vibration_and_Impact/14374061 |
Page generated in 0.0022 seconds