Improving the Self-Consistent Predictions of Texture Development of Polycrystals Incorporating Intragranular Field Fluctuations
In this contribution we present how to implement the calculation of average field fluctuations inside the grains of a thermoelastic aggregate in terms of the derivatives of the stress potential given by the standard linear self-consistent (SC) model, and how this statistical information can be used to generate second-order estimates for the mechanical behavior of nonlinear viscoplastic polycrystals, by means of a rigorous non-linear homogenization procedure. To illustrate the differences between this second-order (SO) self-consistent approach and the classical first-order SC approximations, we compare them in terms of their predictions of the effective behavior of random fcc polycrystals as a function of their rate-sensitivity, and of the texture evolution in hcp ice polycrystals under uniaxial compression. In the latter case, the SO approximation is the only one able to predict a substantial accommodation of deformation by basal slip, even when the basal poles become strongly aligned with the compression direction and the basal slip systems became unfavorably oriented.
Paul Van Houtte and Leo Kestens
R. A. Lebensohn et al., "Improving the Self-Consistent Predictions of Texture Development of Polycrystals Incorporating Intragranular Field Fluctuations ", Materials Science Forum, Vols. 495-497, pp. 955-964, 2005