GEORGIA INSTITUTE OF TECHNOLOGY

Under the provisions of the regulations for the degree

DOCTOR OF PHILOSOPHY

on Tuesday, July 27, 2021

3:00 PM

via

BlueJeans Video Conferencing

https://bluejeans.com/375265351/7080

will be held the

DISSERTATION PROPOSAL DEFENSE

for

Keara Frawley

“Design of Materials Tolerant to Spall Failure at High Strain Rates”

Committee Members:

Prof. Rampi Ramprasad, Advisor, MSE

Prof. Naresh Thadhani, Advisor, MSE

Prof. Chaitanya Deo, ME/MSE

Prof. Chao Zhang, CSE

Jennifer Jordan, Ph.D., Los Alamos National Laboratory

Abstract:

Materials tolerant to dynamic tensile “spall” failure are of interest for applications involving high-velocity impact. Metals and polymers generally have favorable responses to such extreme conditions, and are therefore useful in shock absorbing material applications, such as automotive or body armor. There is, however, a limited understanding of the dependence of spall strength, i.e., resistance to dynamic tensile failure, on typical mechanical properties such as hardness, toughness, strengths, and elastic moduli. The proposed work is aimed at determining the relationship between these properties, henceforth referred to as “proxy” properties, and spall strength, with the goal of developing a predictive model for identifying dynamic tensile spall strengths of metals and polymers.

The specific research tasks will involve employing various methods for collecting/generating a database on spall strengths and proxy properties of metals and polymers through literature survey, plate-on-plate impact experiments, and computational simulations. Potential proxy properties will be correlated to spall strength through data analytic methods. The main objective will be to develop a set of materials design guidelines that can be used to understand the fundamental mechanisms of how metals and polymers fail under high strain rate impact, i.e., dynamic tensile loading, and to predict the spall strength properties of untested materials.