Non-microscopical methods for characterization of microstructures and properties of UFG metals

Author(s)
Michael Zehetbauer, Erhard Schafler, Tamas Ungar
Abstract

The paper reports on non-microscopical methods which allow for close investigation of ultrafine-grained metals especially of those processed by different techniques of Severe Plastic Deformation. These are as follows: (i) X-ray Bragg profile analysis, (ii) electrical residual resistivity, (iii) annealing calorimetry, and (iv) positron annihilation spectroscopy. The advantage of these methods lies in their integration/averaging over a certain sample volume so that they are often much closer to macroscopic physical properties than methods of microscopy; furthermore, the values of quantities obtained are more reliable because of strictly objective rules of determination. Typical quantities being relevant for ultra-fine grained materials are (a) grain size and grain size distribution, (b) long range internal stresses, (c) dislocation densities, and (d) concentration of vacancies and/or vacancy agglomerates. While quantities (a) and (b) are important for all classes of ultra-fine grained materials, those of (c) and (d) particularly occur with nanomaterials processed by severe plastic deformation also being responsible for their specific features such as ductility and the presence of non-equilibrium phases.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Eötvös Loránd University Budapest
Journal
International Journal of Materials Research
Volume
98
Pages
290-298
No. of pages
9
ISSN
1862-5282
DOI
https://doi.org/10.3139/146.101476
Publication date
2007
Peer reviewed
Yes
Austrian Fields of Science 2012
1030 Physics, Astronomy
Portal url
https://ucris.univie.ac.at/portal/en/publications/nonmicroscopical-methods-for-characterization-of-microstructures-and-properties-of-ufg-metals(63e4b39a-c718-4c19-88ad-99cc30caf60d).html