Microstructural damage metrics for failure physics

Safe and reliable design and operation of engineered systems are ultimately limited by our understanding of the physical characteristics of material performance and failure. For structural materials, deformation, damage and fracture are important. The assessment of material state at the microstructural scale is a major factor limiting predictions of system capabilities. Quantitative descriptions and metrics of deformation and damage at the microstructural scale require new methods to understand large numbers of interacting features in the complex mesoscale geometry of actual microstructures. In this paper, we discuss the use of experimental and computational techniques to describe material state. These efforts focus on the integrated use of microtomography, image based models, finite element simulation, the percolation characteristics of deformation and cellular automata simulation of morphology. The results of these efforts produce better physical understanding and mathematical descriptions of mesoscale response.