| Theodore von Kármán Professor of Aeronautics and Mechanical Engineering |
Research Interests Investigation of Dynamic Failure Properties of Metallic Glasses Collaborators: W. Johnson, Caltech; D. Rittel, Technion, Israel; Staff: D. Conner, Caltech The terminology "Metallic Glasses" or "Amorphous Metals" refers to a class of materials that exhibit a metastable amorphous atomic arrangement. Metallic glasses can be formed by a process of very rapid quenching of a melt that "freezes" the microstructure and does not allow for the establishment of the classically observed crystalline structure. In the past, the requirement of rapid quenching has limited the site of metallic glass specimens and has hampered the potential of these solids for structural applications. However, recent advances in the casting of such solids have made it possible for the first time to produce large enough samples suitable for mechanical testing. The project concentrates on the investigation of the extraordinary quasistatic and dynamic fracture properties of metallic glasses. The initial investigation concentrates on glass systems involving Zr, Al and Ti. The quasi-static and dynamic fracture behavior of these unusual materials as well as their localization behavior is studied by using a variety of experimental methods. Recent efforts concentrate on the investigation of energetic issues related to dynamic crack initiation, dynamic crack growth and dynamic branching in such amorphous solids.
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last
update:
05/31/2016