Complex Metallic Alloys: Plasticity and Defects

点击翻译按钮获取中文摘要

The Paketantrag addresses Complex Metallic Alloys (CMAs) as a novel field in materials science with the primary goal to determine and understand the physical properties of a wide range of CMA phases. The Paketantrag scientifically complements the European Network of Excellence “Complex Metallic Alloys”. In the framework of the present proposal we will continue investigating the plastic properties and defects of complex metallic alloys, which are both directly determined by the salient structural features of these materials. Due to their large lattice parameters, conventional deformation mechanisms are prone to failure, and, on the other hand, due to the particular local order in complex metallic alloys, novel deformation mechanisms are possible.The work in the forthcoming period will basically follow three tracks. First, we will carry out an atomic-level transmission electron microscopy study of metadislocation core structures, taking advantage of the availability of state-of-the-art aberrationcorrected microscopes in Jülich, in conjunction with corresponding theoretical work by the partner in Stuttgart. Second we will carry out a full characterization of the plastic behaviour and the defects involved in new systems, such as clathrates, related series of Mg-Zn Laves phases and their isostructural compounds, as well as Taylor phases, which have not been approached before. Third, relating to work carried out in the first funding period, we will carry out comparative studies of related systems (e.g. Bergman-phase variations, hexagonal CMA phases of varying complexity) in order to gain insight into the relations between the local order and the deformation mechanism in CMAs.