|About this Abstract
||MS&T21: Materials Science & Technology
||Probing Defect Properties and Behavior under Mechanical Deformation and Extreme Conditions
||Influence of Microstructural Variation on Spall Failure of Al7085
||Dung-Yi Wu, Chengyun Miao, Christopher DiMarco, K.T. Ramesh, Todd C. Hufnagel
|On-Site Speaker (Planned)
Spallation in ductile metals is a complex, multi-stage and dynamic process involving the nucleation of voids under hydrostatic tensile loading, followed by growth and coalescence of these voids, eventually leading to a final fracture. The influence of microstructure on these processes can be obscured in conventional large-scale spall experiments in which the response is averaged over a large volume of material. In contrast, laser-driven microflyer (LDM) experiments probe smaller volumes, making them more sensitive to local microstructural variations. Using the LDM method on a commercial 7085 aluminum alloy, we observe that increasing the aluminum grain size (via solutionizing heat treatment) causes an increase in the variance of the measured spall strength, even though the average spall strength is largely unchanged. We discuss the relationship between the measured microstructures and the distribution of the spall strength, as well as the morphology of the spall surface.