Session: VIB-04-01

Paper Number: 142199

142199 - Investigation of Elastic Bandgaps on Plastic Wave Propagation 

We explore the dynamics of plastic wave propagation in a periodic, one-dimensional acoustic medium known as a phononic crystal. First, we establish the principles governing the propagation of elastic and plastic waves in uniform, one-dimensional rods using the method of characteristics. Subsequently, we employ a semi-analytical approach, based on the numerical application of the method of characteristics on a fine mesh in space and time, to predict the propagation and behavior of plastic waves in one-dimensional media with spatially varying cross-sectional area profiles. Validation of this approach is achieved through comparison with time-domain finite element simulations with excitation encompassing both elastic and plastic stress amplitudes. Further, we examine a phononic crystal based upon a dogbone-shaped unit cell, investigating its elastic band structure and forecasting its response to both elastic and plastic amplitude excitations using the developed semi-analytical method. We draw special focus on exploring elastic bandgap effects, a characteristic attribute of elastic phononic crystals, and their impact on plastic wave propagation and the resultant residual strains. Furthermore, with the semi-analytical procedure, we establish the basis for the further study of pulse shaping in plastic phononic crystals, a subject of interest for applications related to high-amplitude dynamic tests such as the split Hopkinson pressure bar testing.

Presenting Author: Greg Dorgant Georgia Institute of Technology

Presenting Author Biography: Greg Dorgant is a PhD student in his fourth year at Georgia Tech where he is studying pulse shaping and wave propagation in mechanical metamaterials.

Authors:

Greg Dorgant Georgia Institute of Technology
Washington Delima Kansas City National Security Campus
Michael Leamy Georgia Institute of Technology