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Dynamic events differ significantly from static and quasi-static situations, and
occur ubiquitously in the real world of space, mass and time. Our research approach
employs both experimentation and modeling to obtain in-depth knowledge on failure
mechanisms, including high strain rate deformation, dynamic crack propagation,
microcracking, delamination, penetration, fragmentation and dynamic buckling. The
group's interests have spanned a broad range of materials such as bi-materials,
composites, ceramics, metallic foams, metallic sandwich structures.
Each investigation is carried out with state-of-the-art experimental equipment
consisting of a 3-inch light gas gun, a 1-inch Kolsky bar, and a Fullam miniature
loading stage. We combine a variety of measurement methodologies from strain gage
techniques to novel optical set-ups comprising several laser interferometric
techniques. A Cordin 8-CCD high-speed camera, and full-field DIC (Digital Image
Correlation) are used as diagnostic tools. The high-speed camera is used also to
record the deformation history of structures by means of shadow Moiré. Post mortem
analysis of the samples is carried out with state-of-the-art experimental equipment
including Atomic Force Microscope (AFM), Scanning Electron Microscope (SEM), laser
profilometer, and phase-shift white-light interferometer. The group also developed
computational models to capture the mechanics of dynamic cracking and delamination
as well as meso scale grain level modeling using cohesive interface element.
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