Proceedings Paper for the 59th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference at AIAA SciTech 2019 San Diego, California, USA 7 - 11 January 2019

AIAA 2019-1198

Multiscale Investigation of Piezoresistive Response of Nanocomposite Bonded Explosives (NCBXs) Derived From Electron Tunneling Effects

Krishna Kiran Talamadupula and Gary D. Seidel
Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061-0203, USA

The piezoresistivity derived through the electron hopping or electron tunneling phenomenon due to the presence of CNT reinforcement within insulating polymer systems is studied. This work is primarily structured towards linking the piezoresistivity at the lower scale and using it for microscale level computational studies of Nanocomposite Bonded Explosives (NCBXs). Simmon’s model describing the electron hopping phenomenon is used in conjunction with previously developed computational ability using finite elements in order to determine the nanoscale piezoresistive gage factors for sample nanoscale Representative Volume Elements (RVEs). These gage factors are linked in a multiscale hierarchical fashion to multifunctional microscale level simulations where the energetic grains and the polymer binder channels can be explicitly resolved. Modeling tools developed from previous studies such as interfacial electromechanical cohesive zone modeling are leveraged to capture the complicated multifunctional physical interactions between grain, binder and interface. A parametric sweep is conducted on properties of significant interest such as nanoscale and microscale CNT concentration, alignment and configuration. Effects of these parameter changes on the strain sensing piezoresistive capability of the overall nanocomposite is monitored and commented upon.