Editors: | F. Kongoli |
Publisher: | Flogen Star OUTREACH |
Publication Year: | 2017 |
Pages: | 61 pages |
ISBN: | |
ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
Over the last two decades the processing method �Severe Plastic Deformation�SPD� has impressively demonstrated that nanostructured materials with superior mechanical properties can be produced �top-down� in bulk shape which cannot be achieved with traditional �bottom-up� methods. Now, the optimization of functional properties has been coming into the focus of the community�s research, not at least since the authors reached outstanding successes such as world-records in the figure-of-merit (ZT) of SPD-thermoelectrics, and in the reproducibility in the hydrogen storage of SPD-processed hydrogen storage materials. Recent investigations by the authors clearly suggest that a high density of SPD- induced lattice defects other than of classical grain boundaries can be equally or even more beneficial with respect to functional properties. For example, in case of thermoelectrics, SPD-induced dislocations and/or particular dislocation arrays seem to be most effective in increasing the ZT value. Also in case of soft magnetic materials, regular dislocation arrays from SPD which form low-angle zero-strain nanocrystal boundaries promise new low-coercivity and high-magnetostriction materials, while in case of hydrogen storage, thermally stable SPD-induced vacancy clusters seem to govern the formation / dissolution of the hydride phase. With the know-how to be obtained from systematic investigations, it should be possible to tailor specific defect structures on the nanoscale for optimum functional materials performances with very promising perspectives to practical application.