Microstructural evolution during the heat treatment of nanocrystalline alloys

TitleMicrostructural evolution during the heat treatment of nanocrystalline alloys
Publication TypeJournal Article
Year of Publication2007
AuthorsDetor, AJ, Schuh, CA
JournalJournal of Materials Research
Volume22
Issue11
Pagination3233 - 3248
Date Published2007/11//
Abstract

Nanocrystalline alloys often show exceptional thermal stability as a consequence of kinetic and thermodynamic impediments to grain growth. However, evaluating the various contributions to stability requires detailed investigation of the solute distribution, which is challenging within the fine structural-length-scales of nanocrystalline materials. In the present work, we use a variety of techniques to assess changes in the grain size, chemical ordering, grain-boundary segregation, and grain-boundary structure during the heat treatment of Ni-W specimens synthesized over a wide range of grain sizes from 3 to 70 nm. A schematic microstructural evolution map is also developed based on analytical models of the various processes activated during annealing, highlighting the effects of alloying in nanocrystalline materials.