Authors: JP Thomas F Montheillet SL Semiatin
Publish Date: 2007/07/25
Volume: 38, Issue: 9, Pages: 2095-2109
Abstract
Geometric aspects are a major issue in models of recrystallization that rely on statistical grainpopulation descriptions because the growth of recrystallized grains has to be compensated by the loss of volume of deformed grains thus leading to concomitant variations in all geometric variables A geometric framework for such models was thus designed It is based on mesostructure units MSUs each of which represents an aggregate of similar grains The evolution of MSUs is controlled by two kinds of inputs nucleation rates and grainboundary velocities from which the evolution of microstructure is described in an internally consistent fashion The geometric framework was applied initially to the necklace recrystallization of finegrain microstructures viz the usual form of recrystallization comprising nucleation on initial grain boundaries It was extended to describe particlestimulated nucleation PSN in order to treat geometric effects related to intragranular recrystallization as is found in coarse ingot microstructures For both the necklaceonly and necklaceandPSN cases test cases using simple inputs were performed to validate the behavior of the geometric frameworkThis work was conducted as part of the inhouse research activities of the Metals Processing Group of the United States Air Force Research Laboratory’s Materials and Manufacturing Directorate The support and encouragement of the Laboratory management and the Air Force Office of Scientific Research Dr JS Tiley program manager are gratefully acknowledged One of the authors JPT was supported through Air Force Contract No F3361503D5801
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