Preparation and Characterization of Dysprosium (Dy) Ultrafine Nanocrystalline Structures
By combining the inert-gas condensation with the SPS technology in an entirely closed system with the oxygen concentration below 0.5 ppm, the pure Dy bulk with the ultrafine nanocrystalline structure has been prepared. Thus a novel and efficient route of preparing nano rare-earth metals, as well as metallic nanomaterials that are highly reactive in the air, is proposed. The thermal, physical and mechanical properties of the prepared ultrafine nanocrystalline Dy bulk have been characterized and compared with those of the conventional raw polycrystalline bulk. It is found that in the nanocrystalline Dy bulk, the starting temperature of phase transformation from hexagonal to rhombohedral crystal structure is reduced by 70 °C in comparison with that of the raw polycrystalline bulk. The electrical resistivity of the ultrafine nanocrystalline bulk is slightly increased by a few percent as compared with that of the polycrystalline bulk, while the thermal conductivity is reduced by 28–35%. The microhardness and the elastic modulus of the ultrafine nanocrystalline Dy bulk are found to be remarkably improved as compared with those of the raw polycrystalline bulk, e.g., the microhardness and the elastic modulus are approximately 2.4 and 2.0 times as high as those of the raw polycrystalline bulk, respectively.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Publication date: 2008-02-01
More about this publication?
- Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites