Paper Title:
Macrokinetics Hierarchies of States at Dynamic Superplasticity
  Abstract

Dynamic superplasticity of aluminium alloys is considered from positions of the theory of nonequilibrium phase transitions. Evolution of the open nonequilibrium system by which temperature-rates process in materials is modelled, is investigated within the framework of worked out defining relations with attraction of thermodynamic functions of the response. It is shown, that to peak of superplasticity there corresponds a maximum of a specific thermal capacity. The entropy production in optimum thermomechanical conditions of superplasticity aspires to a minimum which corresponds to formation of qualitative ultrafine-grained structure. With use of the Focker-Plank equation mechanisms of deformation characteristic for superplasticity and boundary conditions are analyzed. It is shown, that at superplasticity the main is the mechanism grain-boundary sliding, and in metastable conditions are added diffusionary processes. Influence of the specified processes in conditions of superplasticity becomes prevailing.

  Info
Periodical
Materials Science Forum (Volumes 575-578)
Edited by
Jitai NIU, Zuyan LIU, Cheng JIN and Guangtao Zhou
Pages
340-344
DOI
10.4028/www.scientific.net/MSF.575-578.340
Citation
D. A. Kitaeva, Y. I. Rudaev, "Macrokinetics Hierarchies of States at Dynamic Superplasticity", Materials Science Forum, Vols. 575-578, pp. 340-344, 2008
Online since
April 2008
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Price
$32.00
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