Lattice orientation effects on void growth and coalescence in fcc single crystals G.P. Potirniche a , J.L. Hearndon a , M.F. Horstemeyer a,b, * , X.W. Ling a a Center for Advanced Vehicular Systems, Mississippi State University, Box 5405, MS 39762, United States b Department of Mechanical Engineering, Mississippi State University, Box 5405, MS 39762, United States Received 10 March 2005 Available online 28 September 2005 Abstract Void growth and coalescence in fcc single crystals were studied using crystal plasticity under uni- axial and biaxial loading conditions and various orientations of the crystalline lattice. A 2D plane strain unit cell with one and two cylindrical voids was employed using three-dimensional 12 poten- tially active slip systems. The results were compared to five representative orientations of the tensile axis on the stereographic triangle. For uniaxial tension conditions, the void volume fraction increase under the applied load is strongly dependent on the crystallographic orientation with respect to the tensile axis. For some orientations of the tensile axis, such as [1 0 0] or [1 1 0], the voids exhibited a growth rate twice as fast compared with other orientations ([1 0 0], [2 1 1]). Void growth and coales- cence simulations under uniaxial loading indicated that during deformation along some orientations with asymmetry of the slip systems, the voids experienced rotation and shape distortion, due mainly to lattice reorientation. Coalescence effects are shown to diminish the influence of lattice orientation on the void volume fraction increase, but noteworthy differences are still present. Under biaxial load- ing conditions, practically all differences in the void volume fraction for different orientations of the tensile axes during void growth vanish. These results lead to the conclusion that at microstructural length scales in regions under intense biaxiality/triaxiality conditions, such as crack tip or notched regions, the plastic anisotropy due to the initial lattice orientation has only a minor role in influenc- ing the void growth rate. In such situations, void growth and coalescence are mainly determined by the stress triaxiality, the magnitude of accumulated strain, and the spatial localization of such plastic strains. Ó 2005 Published by Elsevier Ltd. 0749-6419/$ - see front matter Ó 2005 Published by Elsevier Ltd. doi:10.1016/j.ijplas.2005.06.003 * Corresponding author. Tel.: +1 662 325 5449; fax: +1 662 325 5433. E-mail address: mfhorst@me.msstate.edu (M.F. Horstemeyer). International Journal of Plasticity 22 (2006) 921–942 www.elsevier.com/locate/ijplas