Methodology for the 3-dimensional model-assisted evaluation of polycrystalline materials

The quantitative nondestructive evaluation of tailored microstructures is becoming an increasingly important topic. In aerospace engine materials, NDE methods are needed to characterize polycrystalline grain information related to mean grain sizes, grain size distributions, and misorientation states. In the present research effort, model-assisted ultrasound methods are being developed to study fully 3-dimensional elastic wave propagation and scattering interactions with synthetic and realistic microstructures in nickel superalloy materials. A methodology for integrating synthetic and realistic 3-dimensional microstructure states into ultrasonic finite element models has been developed. The methodology utilizes a recently developed software platform called DREAM.3D, which provides a means for generating, analyzing, and archiving 3-dimensional microstructure volumes. In the present effort, custom Matlab code was developed to synergistically connect the DREAM.3D environment with ultrasound FEM modeling software. The resulting software capability provides a means for accurately representing the full 3-dimensional crystallographic stiffness matrix values in complex polycrystalline systems, where ultrasonic sensing models are being used to understand time-resolved, backscatter ultrasound sensing for enhanced microstructure characterization in aerospace materials.