The thermo-mechanical behavior of materials involves physical, chemical, and mechanical processes that occur on length and time scales that span many orders of magnitude. From an engineering perspective, continuum models that describe behavior at the component length scale are required. By contrast, the physical and chemical processes that drive such behavior often occur on much smaller length scales within the material and can be governed by a hierarchy of length scales. Two such examples are damage evolution and material variability, in which the underlying microstructure of the material plays a key role. In this work, several examples are presented of modeling material systems at the mesoscale, with heterogeneous features of the material microstructure explicitly resolved. This approach is used to better understand the effects of microstructural variability on mechanical performance in additively manufactured metals and to predict the evolution of thermally induced mechanical damage in energetic propellant materials. Insights gleaned from these mesoscale studies are used to inform engineering-scale constitutive models.
Dr. Judith Brown
Senior Member of the Technical Staff in the Fluid and Reactive Processes Department at Sandia National Laboratories, Albuquerque, NM. She holds a B.S. in Aerospace Engineering (2009), and both M.S. (2012) and Ph.D. (2015) degrees in Mechanical Engineering from North Carolina State University, where she developed a novel modeling approach to study laser interaction with energetic aggregates. After joining Sandia in 2015, she has used her background in computational solid mechanics and materials science to study heterogeneous material systems through mesoscale modeling and experimental approaches, with the goal of developing predictive, macroscale constitutive models. Her current work focuses on mechanical behavior in AM stainless steels with localized textures and coupled thermo-mechanical-chemical behavior of energetic materials.