Micrograin Superplasticity: Characteristics and Utilization |
| |
Authors: | Farghalli A. Mohamed |
| |
Affiliation: | Department of Chemical Engineering and Materials Science, University of California, Irvine, CA 92697, USA; E-Mail: ; Tel.: +949-842-5807; Fax: +949-824-2451 |
| |
Abstract: | Micrograin Superplasticity refers to the ability of fine-grained materials (1 µm < d < 10 μm, where d is the grain size) to exhibit extensive neck-free elongations during deformation at elevated temperatures. Over the past three decades, good progress has been made in rationalizing this phenomenon. The present paper provides a brief review on this progress in several areas that have been related to: (a) the mechanical characteristics of micrograin superplasticity and their origin; (b) the effect of impurity content and type on deformation behavior, boundary sliding, and cavitation during superplastic deformation; (c) the formation of cavity stringers; (d) dislocation activities and role during superplastic flow; and (e) the utilization of superplasticity. |
| |
Keywords: | cavitation cryomilling dislocation activity ductility grain boundary sliding high-strain rate superplasticity impurity effect micrograin superplasticity nanocrystalline materials |
|
|