Interpretation of microstructures in high temperature deformation
In each historical period the microstructures produced by high temperature straining were probed by the current technology, this giving rise to new models and theories of rate controlling mechanisms. The progress in understanding has not been monotonic since occasionally theories were developed to high levels of sophistication while overlooking aspects of the substructure which were to become significant. New technologies such as TEM, or SEM-EBSP-OIM have made possible great leaps forward but often leave unresolved problems on a different scale. Experimental observations are presented of substructures in Al with solute, dynamic precipitates, dispersoids and reinforcing particles and in both austenitic and ferritic stainless steels, thus providing a range of crystal structures and stacking fault energies (SFE). After the historical analysis, the current view of the hot-worked state will be presented with comparison of the conflicting theories. The analysis is centered on dislocation strain and there is only mention of pertinent interactions with grain boundary related deformation. The first seventy references point to research being done during the period that Prof. Julia Weertman (also the author) was pursuing research for the Ph.D. or starting a teaching career. it was an exciting time in which the applications of dislocation theory to cold working, recovery and creep were being confirmed by intragranular structural observations. Both the new modes of microscopic examination and the enhanced theories made possible the surge in fundamental understanding of hot working mechanisms that were summarized in the following twenty classic reviews. Finally, the remaining fifty references survey the current research which attempts to clarify the more complex details of the mechanisms: dynamic recovery (DRV) and dynamic recrystallization (DRX).
- Research Organization:
- Concordia Univ., Montreal (CA)
- OSTI ID:
- 20014198
- Resource Relation:
- Conference: 1999 TMS Fall Meeting, Julia R. Weertman Symposium: Advanced Materials for the 21st Century, Cincinnati, OH (US), 10/31/1999--11/04/1999; Other Information: PBD: 1999; Related Information: In: Advanced materials for the 21st century: The 1999 Julia R. Weertman symposium, by Chung, Y.W.; Dunand, D.C.; Liaw, P.K.; Olson, G.B. [eds.], 585 pages.
- Country of Publication:
- United States
- Language:
- English
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