This renewal award by the Division of Materials Research to Georgia Institute of Technology is to develop general and unbiased practical quantitative fractographic techniques for quantitative characterization of fracture micro-mechanisms and microstructural geometry observed in the fracture surfaces. In addition, with this award, Professor Gokhale will develop new stereological and digital image analysis techniques for quantitative characterization of the geometry of three-dimensional (3D) microstructures, and techniques for mathematical representation and computer simulation of the microstructural geometry. The study of microstructures is central to science and engineering disciplines where microscopes are used to characterize internal morphological structures. The geometry of fracture surfaces often contains key information concerning the microstructural features that play a dominant role in the deformation and fracture processes of materials. The specific scientific tasks of this award would be development of stereological and image analysis techniques for unbiased estimation of n-point statistical correlation functions for the features in the 3D microstructures and the fracture surfaces. Development of the techniques for computer simulations of 3D microstructures statistically similar to the corresponding real microstructures, and development of image analysis based techniques for 3D quantitative fractography will be part of this study. Techniques for quantitative microstructure characterization of thin films and bulk nano-structured materials would also be explored.
The intrinsic merit of this research is in the development of the enabling techniques, tools, and methodologies for quantitative characterization, mathematical modeling, and representation of the complex geometries of microstructures and non-planar fracture surfaces in 3D space. The general stereological and image analysis techniques to be developed would be applicable for quantitative characterization of any internal structure contained in any reference space. For example, these techniques will equally be applicable for quantitative characterization of pores in concrete, nerve fibers and capillaries in biological tissues, roots in plants, air sacks in lungs, minerals in rock, and pore channels in soils. The fractographic techniques would be applicable to material fracture surfaces as well as to frozen fracture surfaces of biological tissues. Human resource development occurs though participation of graduate and undergraduate students, outreach through involvement in the Summer Undergraduate Research Fellowship (SURF) and Research Experience for Teachers (RET) programs, continuing education through teaching of short courses/workshops, and dissimilation of the research results through publications. An Internet website for quantitative microstructure database will be created.
