Header menu link for other important links
X
Numerical study of the stress state of a deformation twin in magnesium
M. Arul Kumar, , S.R. Niezgoda, R.A. Lebensohn, Carlson N. Tomé
Published in Elsevier Ltd
2015
Volume: 84
   
Pages: 349 - 358
Abstract
We present here a numerical study of the distribution of the local stress state associated with deformation twinning in Mg, both inside the twinned domain and in its immediate neighborhood, due to the accommodation of the twinning transformation shear. A full-field elastoviscoplastic formulation based on fast Fourier transformation is modified to include the shear transformation strain associated with deformation twinning. We have performed two types of twinning transformation simulations with: (i) the twin completely embedded inside a single crystal and (ii) the twin front terminating at a grain boundary. We show that: (a) the resulting stress distribution is more strongly determined by the shear transformation than by the intragranular character of the twin or the orientation of the neighboring grain; (b) the resolved shear stress on the twin plane along the twin direction is inhomogeneous along the twin-parent interface; and (c) there are substantial differences in the average values of the shear stress in the twin and in the parent grain that contains the twin. We discuss the effect of these local stresses on twin propagation and growth, and the implications of our findings for the modeling of deformation twinning. © 2014, Elsevier Ltd. All rights reserved.
About the journal
JournalData powered by TypesetActa Materialia
PublisherData powered by TypesetElsevier Ltd
Open AccessNo
Concepts (11)
  •  related image
    Deformation
  •  related image
    Grain boundaries
  •  related image
    Shear stress
  •  related image
    Single crystals
  •  related image
    Stress concentration
  •  related image
    Crystal plasticity
  •  related image
    Deformation twinning
  •  related image
    HCP MATERIALS
  •  related image
    LOCAL STRESS DISTRIBUTION
  •  related image
    SHEAR TRANSFORMATION
  •  related image
    Twinning