INT 9605232 Vitek This U.S.-Czech research project between Vaclav Vitek of the University of Pennsylvania and his partners, Vaclav Paidar of the Czech Institute of Physics and Mojmir Sob of the Czech Institute of the Physics of Materials, will examine metastable structures in the lamellar TiAl (titanium aluminum), a ductile intermetallic compound. The research plan entails analyzing configurations produced by large scale distortions that transform the initial structure creating new structures with different symmetries. Two types of distortions will be considered: 1) large homogeneous straining and 2) shuffling of atomic planes. The collaborative work is expected to yield new knowledge about these atomic interfacial structures, specifically, the lattice transformations connecting the interface, including dislocations and twin nuclei. Results will help explain the high ductility and toughness of the lamellar TiAl by characterizing the bonding in an ideal lattice and in defective regions. Such information may be useful in future production of strong, light density-high temperature tolerant intermetallic compounds for rotating machinery and aerospace applications. This project in materials research fulfills the program objective of advancing scientific knowledge by enabling leading experts in the United States and Eastern Europe to combine complementary talents and pool research resources in areas of strong mutual interest and competence. ??
