AEROSPACE ENGINEERING

Abstract

The distribution of grain orientations in crystalline materials, commonly referred to as texture or grain structure, strongly influences the macroscopic properties of polycrystals. Texture evolves rapidly in the presence of extreme thermomechanical loads accompanying various manufacturing processes. Therefore, establishing the process-structure relationship is one of the most challenging technologically-relevant open problems of materials science. Recovery, recrystallization, and grain growth are the three fundamental phenomena responsible for texture evolution. Recovery is an energy-minimizing process of rearranging dislocation networks to form cells. These cells act as potential nuclei for spontaneous growth, resulting in recrystallization of defect-free grains. The subsequent evolution of defect-free grains is referred to as grain growth. These phenomena are uniquely challenging to model since the grain microstructure and deformation evolve at the same time scale. In this talk, we will describe key challenges in modeling texture evolution, and our recent work on the formulation of a hierarchical multiscale framework spanning the atomic, meso, and macro scales. We will focus on the coevolution of grain microstructure and deformation and the development of fast algorithms for evolving surfaces. This work sets the stage for an experimental- and data-driven modeling paradigm to establish process-structure relationships.

Speaker

Dr. Nikhil Admal

Assistant Professor in the Department of Mechanical Science and Engineering at UIUC. Prior to joining UIUC, Dr. Admal was a Postdoctoral Research Scholar at UCLA. He received his Ph.D. in Aerospace Engineering and Mechanics from the University of Minnesota in 2014. Currently, the focus of his research is on modeling recovery, recrystallization, and grain growth in crystalline materials to establish process-structure relationships, and on the mechanics of graphene-metal interfaces. Dr. Admal is a recipient of the Institute for Digital Research and Education (IDRE) Postdoctoral Fellowship at UCLA, and the Doctoral Dissertation Fellowship from the University of Minnesota.