Acquisition of X-Ray Computed Tomography System for the Modeling and Characterization of Materials with Microstructure

Washington State University, Pullman WA

Investigators

Abstract

OIA-0116793 PI Eyad Masad Institution Washington State University Title "Acquisition of x-Ray Computed Tomgraphy System for the Modeling and Characterization of Materials with Nanostructure Abstract This MRI award is for the acquisition of an X-ray computed tomography (CT) system for non-invasive evaluation of the microstructure of engineering materials. The system is unique for the visualization of three-dimensional of microstructural features in the interior of opaque solid objects. The X-ray CT system will be used to perform detailed observations of the microstructural features associated with granular deformation. It will also be used in the development of new generation ceramics and metal matrix composites. The focus of the first research is on the development of a microstructure based continuum model to study the deformation and locialization in granular materials. The model is based on crystal plasticity but inclused two microstructure length scales; one associated with the plastic curvature (orientation re-distribution) and the other one is related to the porosity re-distribution. This study is unique in that the microstructure model parameters are determined directly from microscopic measurements. The study will lead to analytical methods for modeling strain localization not only in laboratory specimens, but also inpractical boundary value problems in geotechnical engineering. The outcome of this work will also have implications to the modeling of other types of materials that exhibit deformation instabilities and shear banding such as metals and composites. The engineering behavior of ceramics and metal matrix composite materials is controlled by the microstructure of several levels. Therefore, the second study combines microscopic and macroscopic principles and develops multiscale mosels for their description. The multiscale model parameters are determined directly from X-ray CT measurements. Use of such models will enable the design and development of new materials with tailored microstructures. In addition to the above major studies, a host of other research activities from different disciplines at Washington State University will benefit from the proposed system. The unique capabilities of the system will contribute substantially to the extramural funding, and encourage more collaboration with other institutions and research centers.