A. Gokhale, Y. Mao, A. Sreeranganathan, Georgia Institute of Technology, Atlanta, GA; H. Singh, BBSB Engineering College, FATEHGARH SAHIB, India; S. Lieberman, Exponent Failure Analysis Associates, Menlo Park, CA; J. Harris, Stanford University, Stanford, CA
Current methodologies for microstructure simulations mostly involve idealized simple particle/feature shapes; uniform-random spatial distribution of microstructural features; and isotropic feature orientations. However, the corresponding “real” microstructures often have complex feature shapes/morphologies; non-random/non-uniform spatial distributions; and partially anisotropic feature orientations. Consequently, such simulations do not capture these aspects of microstructural reality. In this contribution, we present a methodology that enables simulations of “realistic” microstructures where feature shapes/morphologies, spatial arrangement, and feature orientations are statistically similar to those in the corresponding real microstructures. The methodology is applied for simulations of microstructures of TiB whiskers in Boron modified Ti-alloys, discontinuously reinforced Al-alloy composites, and coarse constituent particles in wrought Al-alloys. In each case a small set of simulation parameters is used for the generation of these microstructures. The methodology enables the generation of a set of “virtual” microstructures that cover a wide range of process conditions. These virtual microstructures are then implemented in finite element (FE) based computations to simulate local stress distributions and stress-strain curves of the corresponding virtual materials. The methodology can provide useful input for materials design and can decrease the number of experiments needed for material development.
Summary: Current methodologies for microstructure simulations mostly involve idealized simple particle/feature shapes; uniform-random spatial distribution of microstructural features; and isotropic feature orientations. However, the corresponding “real” microstructures often have complex feature shapes/morphologies; non-random/non-uniform spatial distributions; and partially anisotropic feature orientations. Consequently, such simulations do not capture these aspects of microstructural reality. In this contribution, we present a methodology that enables simulations of “realistic” microstructures where feature shapes/morphologies, spatial arrangement, and feature orientations are statistically similar to those in the corresponding real microstructures. The methodology is applied for simulations of microstructures of TiB whiskers in Boron modified Ti-alloys, discontinuously reinforced Al-alloy composites, and coarse constituent particles in wrought Al-alloys. In each case a small set of simulation parameters is used for the generation of these microstructures. The methodology enables the generation of a set of “virtual” microstructures that cover a wide range of process conditions. These virtual microstructures are then implemented in finite element (FE) based computations to simulate local stress distributions and stress-strain curves of the corresponding virtual materials. The methodology can provide useful input for materials design and can decrease the number of experiments needed for material development.
