The Fall 2022 MatSE 590 for graduate students consists of an exciting and jam-packed schedule. MATSE 590 is a colloquium (1-3 credits) consist of a series of individual lectures by faculty, students, or outside speakers.
Graduate students will receive a weekly email with information via @psu.edu email. Graduate students are required to attend all 590 Seminars. If you have any questions, please email GradOffice@matse.psu.edu.
September 8, 2022
“Slip Localization and the Prediction of Fatigue Strength of Polycrystalline Alloys”
Jean-Charles Stinville, Assitant Professor, Materials Science and Engineering, University of Illinois at Urbana-Champaign
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, hexagonal close-packed, and body-centered cubic 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.
Biographical Information
J.C. Stinville holds an aerospace engineering Master’s degree and a Ph.D. in Materials Science from the French Grande École, ENSMA. In 2015, as a Researcher, he joined the Materials Department at the University of California Santa Barbara. He is presently an Assistant Professor in the Materials Science and Engineering Department at the University of Illinois at Urbana-Champaign (UIUC) since 2021. His research group characterizes and models deformation processes for mechanical properties prediction and material design for energy, transportation, and environmental applications. He received the 2016 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. As an assistant professor, he is involved in the UIUC hard-material curriculum and teaches experimental characterization, metallurgical materials science, and alloy design classes.