Scale up of nanometals production
Warsaw University of Technology, Faculty of Materials Science and Engineering (InMat), Wołoska 141, Warszawa 02-507, Poland
Nano-crystalline metals and alloys can be fabricated by various processing methods, which can be classified into: bottom-up (nanostructure is built up atom by atom, molecule by molecule) and top-down (coarse grained structures refined into nano-scaled ones employing, among others, severe plastic deformation).
In the present work, two different methods for producing relatively large products of nanometals are presented, namely (i) SPD induced grain refinement, (ii) plastic consolidation of nano-powders. SPD grain refinement has been implemented by equal channel angular pressing, ECAP, and hydrostatic extrusion, HE. Plastic consolidation of powder and ribbons was conducted by warm extrusion. The materials used in the experiments were 5XXX series aluminium alloys.
It will be demonstrated that by applying various fabrication routes for a given chemical composition, diverse nano-structures can be obtained, which differ in terms of grain size and shape, grain boundary character and dislocation density. As a result, the alloys also differ significantly in the mechanical properties and thermal stability. The findings are discussed in terms of the possibilities for optimizing properties of the bulk-nano-metals.
Presentation: Invited oral at Warsaw and Karlsruhe Nanotechnology Day, by Malgorzata Lewandowska
See On-line Journal of Warsaw and Karlsruhe Nanotechnology Day
Submitted: 2011-09-15 12:59 Revised: 2011-09-15 12:59