Title: Powder metallurgy on its way to nanocrystalline structures

Authors: B. Gunther, H.-D. Kunze, B. Scholz

Addresses: Fraunhofer Institute for Applied Materials Research, Lesumer Heerstr. 36, 2820 Bremen 77, Germany ' Fraunhofer Institute for Applied Materials Research, Lesumer Heerstr. 36, 2820 Bremen 77, Germany ' Fraunhofer Institute for Applied Materials Research, Lesumer Heerstr. 36, 2820 Bremen 77, Germany

Abstract: Metallic and ceramic dense nanocrystalline (nc-)materials with average grain sizes of about 5 to 100 nm may be produced by means of powder technology at relatively low temperatures. This is achieved by using nano-dispersed, i.e. highly sinter-active starting powders. It is the extremely high grain-/phase-boundary area that determines the unusual properties of the resultant PM-components. The various suitable PM-methods for the production of pure as well as composite nc-materials are shortly reviewed including the sol-gel-process, mechanical alloying and the inert gas evaporation method. Some of the fascinating potentials of PM-fabricated nc-materials due to their peculiar magnetic, electronic and mechanical behaviour are elucidated.

Keywords: powder metallurgy; ultrafine powder; inert gas evaporation; mechanical alloying; sol-gel; nanocrystalline structures; nanocrystalline materials.

DOI: 10.1504/IJMPT.1993.036546

International Journal of Materials and Product Technology, 1993 Vol.8 No.2/3/4, pp.351 - 360

Published online: 04 Nov 2010 *

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