MateriAlZ Seminar: Jean-Charles Stinville
Friday, September 9, 2022, 10:50 am MST
Jean-Charles Stinville
Assistant Professor of Materials Science and Engineering
University of Illinois at Urbana-Champaign
"Slip Localization and the Prediction of Fatigue Strength of Polycrystalline Metals"
Zoom link | Passcode: 318925
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Abstract
With increasing applied stress, metallic materials experience irreversible deformation, manifested in localized slip events that result in unexpected fatigue failure upon repeated cycling. Recent advances in accelerated fatigue testing, in-situ electron microscopy, digital image correlation methods, and multi-modal data analysis have been integrated to quantitatively characterize the evolution of these slip events from the earliest stages of cycling at the nanometer scale over large fields of view in relation to material structure. Statistical analyses of slip events for a large collection of materials with face-centered cubic (fcc), hexagonal close-packed (hcp), and body-centered cubic (bcc) structures have been performed. Relations between the yield and ultimate tensile strength, cyclic fatigue strength, and slip events characteristics are uncovered. It is observed that the fatigue strength of fcc, hcp, and bcc metallic alloys can be predicted by the amplitude of slip localization during the first cycle of loading. These observations provide a physical basis for well-known empirical fatigue laws and enable a rapid material design method by predicting fatigue strength via measurement of slip localization amplitude.
Bio
Jean-Charles Stinville holds a Ph.D. in Solid Mechanics, Materials Science, and Mechanical Engineering. His Ph.D. work on the mechanical properties of plasma-treated stainless steels for nuclear application has been awarded the highest academic distinction in the French educational system. In 2012, he joined the research group of T.M. Pollock at the University of California Santa Barbara, where he became a Specialist in 2015. He has led efforts around experimental developments of in-situ mechanical characterization techniques. He received the Hetényi Award, which is given annually for the best research paper published in Experimental Mechanics. He has also been recognized for his contribution to understanding the fatigue properties of nickel-based superalloys and was awarded the Best Paper Award at Superalloy2018. He holds appointments in the Materials Science and Engineering Department and the Materials Research Laboratory as an assistant professor at the University of Illinois at Urbana-Champaign. His research interests include metallic materials' mechanical and environmental performances for high temperature, energy, and environmental applications.