U.S.-Czech Materials Research on Metastable Structures in the Intermetallic Compound TiAl

宾夕法尼亚大学的Vaclav Vitek和他的合作伙伴，捷克物理研究所的Vaclav Paidar和捷克材料物理研究所的Mojmir Sob共同开展了一个美国-捷克研究项目，该项目将研究层状TiAl（钛铝）（一种延展性金属间化合物）中的亚稳结构。研究计划需要分析由大规模扭曲产生的构型，这些扭曲改变了初始结构，创造出具有不同对称性的新结构。将考虑两种类型的畸变：1)大的均匀应变和2)原子平面的洗牌。这项合作工作有望产生关于这些原子界面结构的新知识，特别是连接界面的晶格变换，包括位错和双核。结果将有助于解释板层TiAl的高延展性和韧性，通过表征在理想晶格和缺陷区域的结合。这些信息可能对未来生产用于旋转机械和航空航天应用的强、轻密度、耐高温的金属间化合物有用。这个材料研究项目通过使美国和东欧的顶尖专家在共同感兴趣和能力强的领域结合互补的人才和集中研究资源，实现了推进科学知识的计划目标。?？

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. ??