**Acknowledgments**

This work was conducted with support of the Office of Naval research, Code 30. We appreciate the help that Chris Clay and John Gibson provided to conduct the shock tube tests. We thank Jing Bing from University of New Mexico and JEOL, USA Inc. for facilitating the collection of TEM data. We also thank Alexey Peshkovsky, from Industrial Sonomechanics for guidance using the transducer.
