MSE Seminar Series: New Insights on Polycrystals from Multimodal 3D TriBeam Tomography

Speaker

Tresa Pollock
Alcoa Distinguished Professor of Materials
University of California, Santa Barbara

Abstract

From the earliest days of materials science, Cyril Stanley Smith recognized the importance of polycrystal structure and the constraints on its development and evolution in inorganic metallic, ceramic and geological materials. A wide spectrum of mechanical, functional and environmental properties depend sensitively on polycrystalline structure, which is typically anisotropic with superimposed chemical inhomogeneity. The development of a new instrument, designated as the TriBeam, will be described. The TriBeam hosts electron, focused ion and femtosecond laser beams in one chamber and allows for extremely rapid (of the order of seconds) in-situ serial sectioning of mm²-scale surfaces with sub-micron slice thickness. The electron beam and other in-situ detectors enable acquisition of chemical, structural and crystallographic information in 3D for a wide spectrum of materials. New insights from high resolution 3D datasets will be discussed, including the influence of rare features of polycrystal structure on cyclic loading, void nucleation and the structure of 3D printed metallic materials. The challenges and opportunities for large volumes of 3D multimodal data will be discussed.

Biography

Tresa Pollock is the Alcoa Distinguished Professor of Materials at the University of California, Santa Barbara. Pollock’s research focuses on the mechanical and environmental performance of materials in extreme environments, unique high temperature materials processing paths, ultrafast laser-material interactions, alloy design and 3-D materials characterization. Pollock graduated with a B.S. from Purdue University in 1984, and a Ph.D. from MIT in 1989. She was employed at General Electric Aircraft Engines from 1989 to 1991, where she conducted research and development on high temperature alloys for aircraft turbine engines and co-developed the single crystal alloy René N6 (now in service). Pollock was a professor in the Department of Materials Science and Engineering at Carnegie Mellon University from 1991 to 1999 and the University of Michigan from 2000 – 2010. Professor Pollock was elected to the U.S. National Academy of Engineering in 2005, the German Academy of Sciences Leopoldina in 2015, and is a DOD Vannevar Bush Fellow and Fellow of TMS and ASM International. She serves as Editor in Chief of the Metallurgical and Materials Transactions family of journals, served as Interim Dean of the College of Engineering at UCSB from 2021 – 2023 and was the 2005-2006 President of The Minerals, Metals and Materials Society.