Failure, and a Career That is Anything But: An LMD Symposium Honoring J. Wayne Jones: Keynote Session
Sponsored by: TMS Light Metals Division, TMS: Magnesium Committee
Program Organizers: Victoria Miller, University of Florida; Michael Caton, US Air Force Research Laboratory; Nikhilesh Chawla, Purdue University; Trevor Harding, California Polytechnic State University; Paul Krajewski, General Motors Corporation; Tresa Pollock, University of California - Santa Barbara
Monday 2:00 PM
February 28, 2022
Room: 209B
Location: Anaheim Convention Center
Session Chair: Victoria Miller, University of Florida
2:00 PM Introductory Comments
2:10 PM Keynote
Reducing Uncertainty: Reflections on Establishing Life Limits: James Larsen1; Sushant Jha2; Reji John1; Andrew Rosenberger1; Dennis Buchanan2; John Porter, III2; Adam Pilchak3; Patrick Golden1; 1Air Force Research Laboratory; 2University of Dayton Research Institute; 3Materials Resources, LLC
Uncertainty in fatigue life prediction is among the most limiting structural design factors for fracture-critical metallic components in advanced aerospace systems. This presentation will highlight sources of variability and uncertainty in fatigue, and will offer insights into factors that control the lower-bound fatigue life limit. Anchored in the principles of damage tolerance, a perspective will be outlined for modeling fatigue life limits and for deconstructing the sources of variability in fatigue response. The approach seeks to optimize safety, reliability, and affordability, while utilizing the alloy’s full inherent performance capability. Efforts to validate such probabilistic models vs. field experience are finding new opportunities through emerging tools for microstructural characterization, health awareness, and Integrated Computational Materials Science.
2:55 PM Keynote
Strain Localization and Very High Cycle Fatigue: Jean-Charles Stinville1; Alice Cervellon1; Tresa Pollock1; 1University of California, Santa Barbara
Very high cycle fatigue testing at 20 kHz in an effective approach understanding mechanisms of failure in turbine airfoil materials as well as for rapid characterization of the fatigue properties of a wide spectrum of structural materials. The elevated temperature VHCF behavior of single crystal superalloys as a function of temperature and mean stress will be discussed. Strain localization and slip irreversibility in fatigue has been studied over a broad set of structural materials using high resolution digital image correlation. The relationships between the yield and ultimate tensile strength, VHCF fatigue strength and the amplitude and spacing of slip localization events are revealed for the first time. Interestingly, the fatigue strength of a large collection of fcc, hcp and bcc metallic alloys in the VHCF regime can be predicted by the amplitude of slip localization during the first cycle of loading.
3:40 PM Break
4:00 PM Keynote
Accelerating Understanding of Fatigue of Metals: John Allison1; 1University of Michigan
Failure of metals by fatigue is a subject that has continued to fascinate scientists and trouble engineers for many, many decades. For a few of these decades, the author has had the good fortune of working with the symposium honoree in this endeavor. This talk will provide an overview of many topics we have worked on together involving crack tip phenomena, small crack propagation and its use in predicting processing effects on fatigue response of metals and use of ultrasonic fatigue to rapidly characterize high cycle fatigue behavior and understand the interaction of small cracks with grain boundaries. Efforts to accelerate understanding of cyclic deformation and fatigue crack propagation using high energy diffraction methods and crystal plasticity models will be also reviewed.
4:45 PM Keynote
Automotive Unobtanium: Material Challenges for the Future of Transportation: Paul Krajewski1; Nancy Johnson1; Xingyi Yang1; Selina Zhao1; Janet Robincheck1; Whitney Poling1; Kai-Han Chang1; Andrea Corrion2; 1General Motors Corporation; 2HRL Laboratories, LLC.
The future of ground transportation promises significant changes to how vehicles travel, how they are propelled, and how customers experience the trip. Materials are the common enabler for this future, with the ability to impact autonomous driving, electrification, cabin experience and connectivity while providing superior performance and sustainable, green vehicles. This talk will first provide a vision for the future of automobiles and then identify key challenges in each of these areas including materials for batteries, sensors, displays, structures, and a variety of interior systems. The goal is to provide targets for the materials research community to help drive the development of these enabling materials.