Professor Tresa M. Pollock - 2023 Acta Materialia Gold MedalThe recipient of the 2023 Acta Materialia Gold Medal is Professor Tresa M. Pollock, the Alcoa Distinguished Professor of Materials at the University of California Santa Barbara.
Prof. Pollock received her Ph.D. from the Massachusetts Institute of Technology in 1989, conducting research with Professor Ali Argon on strengthening mechanisms in high temperature materials. Prior, she received a B.S. in Metallurgical Engineering from Purdue University while also working at Rolls Royce in Indianapolis, IN on fatigue and fracture of aerospace alloys. Following her Ph.D., Prof. Pollock worked as a research engineer at GE Aircraft Engines, where she was co-inventor of the single crystal turbine airfoil superalloy René N6, which is presently in service. Her academic career began at Carnegie Mellon University, where she moved through the academic ranks from Assistant to Full Professor and led multi-investigator research programs on intermetallic compounds. In 2000, she moved to the University of Michigan, where she was the L.H. and F.E. Van Vlack Professor of Materials Science and Engineering. At Michigan she led collaborative research efforts on high temperature magnesium alloys for automotive applications, ultrafast laser-material interactions and unique crystal growth processes. In 2010 Prof. Pollock joined the faculty at the University of California, Santa Barbara where she has continued her research and served as Department Chair of Materials (2011 – 2017), Associate Dean (2018 – 2021) and Interim Dean of Engineering (2021 – present).
Prof. Pollock’s overarching research interests include the mechanical and environmental performance of materials in extreme environments, unique high temperature materials processing paths, ultrafast laser-material interactions, alloy and coating design and 3-D materials characterization. In her most recent research, new alloys and tailored powders have been developed for 3D printing of aerospace components. Integrating suites of new computational and experimental design tools developed over the past decade, a Co-Ni superalloy with exceptional high temperature strength has been designed and demonstrated to have a high tolerance to defect formation over a wide range of laser- and electron beam powder bed printing conditions. In parallel, new resonant ultrasound spectroscopy approaches have been developed to non-destructively characterize the inherently anisotropic structure that develops during 3D printing and along other advanced materials processing paths. Prof. Pollock’s research on 3D printing builds upon her earlier research on solidification of Ni-base alloys, where she studied mechanisms of breakdown of single crystal dendritic growth and demonstrated the thermal gradient and mechanical property benefits of the withdrawal of single crystals into liquid metal coolant baths during Bridgman growth.
Prof. Pollock and her team have invented an innovative in-situ tomography platform, designated the “TriBeam”. The instrument is the first to combine femtosecond (10-15 s) laser beam, an ion beam, and an electron beam, along with suites of detectors. The system enables 3D imaging of materials and makes it possible to acquire, via rapid layer-by-layer ablation, a unique set of multimodal information about materials chemistry and structure, which is then reconstructed into 3D data sets. This technique is applicable to virtually all classes of materials and provides previously unavailable 3-D structural and chemical information with sub-micron resolution over >mm3 volumes needed for material property modeling. At the same time, new methods for distortion correction and merging of sub-micrometer 3D multimodal data (chemical + structural + crystallographic) that use machine learning approaches have been developed. The 3D data derived from this technique have enabled new insights to failure mechanisms and have guided the development of models for mechanical degradation of nickel-base, titanium-base and refractory and multi-principal element alloys that are critical to the safety and performance of advanced engineering systems.
Prof. Pollock and collaborators have utilized the scanning electron microscope as an experimental platform for other novel in-situ experiments. In-situ straining stages integrated with a new digital image correlation technique that implements Heaviside functions has enabled strain localization during monotonic and cyclic loading to be studied at previously unreachable resolution over statistically relevant volumes of material.This has provided new insights on the irreversibility of slip during fatigue, the role of triple junctions in promoting slip band formation and enabled fatigue strength to be predicted from the localization behavior during the first cycle of loading for a wide spectrum of metallic materials. Techniques for dynamic imaging of plastic deformation processes by transmission scanning electron microscopy have been developed, enabling for the first time, observation of dislocation dynamics in the lower voltage imaging conditions of the SEM. This approach has provided new insights on high temperature deformation mechanisms in superalloys that involve cooperative precipitate shearing and dynamic formation and removal of superlattice intrinsic stacking faults and antiphase boundaries High throughput methods for mapping these fault energies over muti-dimensional composition space have provided another suite of design tools for alloys containing ordered precipitates. Combinatorial and high throughput screening methods have also enabled design of new multilayered oxidation-resistant coating systems for metallic and refractory alloy substrates.
Professor Pollock has played a leadership role in the development and advancement of the US Materials Genome Initiative (MGI), the federal multi-agency initiative aimed at discovering, manufacturing, and deploying advanced materials twice as fast and at a fraction of the cost, compared to traditional methods. The initiative has created policy, resources, and infrastructure to support the adoption of methods for accelerating materials development. Previous to MGI, she co-chaired the 2008 National Academy of Engineering study on “Integrated Computational Materials Engineering” (ICME) and led the organization of a large number of national and international workshops and symposia on ICME and the MGI. Professor Pollock has also provided leadership for the materials profession, with a focus on junior professionals, in her role as President of the Minerals, Metals and Materials Society (TMS) in 2005 – 2006 and as Editor-in-Chief of the Metallurgical and Materials Transactions family of journals.
Professor Pollock has been recognized by a number of awards, honorary lectureships and membership in national academies. She is a Fellow of TMS and ASM and was elected to the US National Academy of Engineering in 2005. In 2015, she received the Acta Materialia Hollomon Award in Materials and Society and the German National Academy of Sciences Leopoldina She was selected as a Department of Defense Vannevar Bush Faculty Fellow in 2017. She received the TMS Morris Cohen Distinguished Achievement Award and the Society for Engineering Mechanics Hentéyl Award (2018), the Institute of Metals Robert Franklin Mehl Award (2020) and the honorary membership in the Société Française de Métallurgie et de Matériaux (2021).
In accepting the 2023 Acta Materialia Gold Medal, Professor Pollock acknowledges with deepest gratitude her students, postdocs, professional colleagues, and collaborators throughout the world.
Professor Pollock will receive the 2023 Acta Materialia Gold Medal at the TMS Annual Meeting in San Diego, CA, March 19-23, 2023.