Berlin 2008 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 11: Nanostructured Materials III

MM 11.6: Vortrag

Montag, 25. Februar 2008, 16:00–16:15, H 0107

Three-dimensional tomographic EBSD measurements of the crystal topology in heavily deformed ultra fine grained pure Cu and Cu-0.17wt%Zr obtained from ECAP and HPT — •Anahita Khorashadizadeh, Myrjam Winning, and Dierk Raabe — Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany

Obtaining knowledge on the grain boundary topology in three dimensions is of great importance as it controls the recrystallization and grain growth behaviour of polycrystalline materials. In this study, the three dimensional distribution of grain boundaries and the grain topology of the as-deformed condition have been investigated using three-dimensional orientation microscopy (3D electron backscattering diffraction, EBSD) measurements in ultra fine grained pure Cu and Cu-0.17wt%Zr. Two different methods of severe plastic deformation were used to produce the ultra fine grained structures: equal-channel angular pressing (ECAP) and high pressure torsion (HPT). The experiments are conducted using a dual-beam system for 3D-EBSD. The approach is realized by a combination of a focused ion beam (FIB) unit for serial sectioning with high-resolution field emission scanning electron microscopy equipped with EBSD. The work demonstrates that the new 3D EBSD-FIB technique provides a new level of microstructure information that cannot be achieved by conventional 2D-EBSD analysis. Such information is of great importance in studying metallurgical behaviours which depend on the 3D grain boundary topology (such as grain growth, recrystallization).