MMAE Seminar - Dr. Sammy Tin - Design of Fatigue Resistant Ni-Base Superalloys via Meso-scale Engineering
Armour College of Engineering's Mechanical, Materials, and Aerospace Engineering Department will welcome Dr. Sammy Tin, a Professor of Materials Engineering in the Department of Mechanical, Materials, and Aerospace Engineering at the Illinois Institute of Technology to present his lecture, Design of Fatigue Resistant Ni-Base Superalloys via Meso-scale Engineering.
Abstract
In recent years, microstructure explicit fatigue models for polycrystalline Ni-base superalloys have been developed that confirm strain localization around microstructural features, primarily at twin boundaries, prior to nucleation of fatigue cracks. With this improved understanding of fatigue crack nucleation mechanisms, an ICME framework was used to identify the optimized microstructures in a commercial Ni-based superalloy, RR1000. A finite element based crystal plasticity model was used to inform the design of microstructures and identify desirable meso-scale grain boundary character distributions that could be varied to enhance the fatigue performance of RR1000. Following which, innovative hot deformation based grain boundary engineering techniques were used to systematically vary the grain boundary character distributions in small-scale forgings of RR1000 to improve their damage tolerance. Small-scale forging trials of RR1000 were conducted to produce controlled microstructures with varying grain boundary character distributions. Experimental results will be presented and the implications for design and life prediction assessment will be discussed.
Biography
Dr. Sammy Tin is a Professor of Materials Engineering in the Department of Mechanical, Materials, and Aerospace Engineering at the Illinois Institute of Technology. Professor Tin's research has focused on the composition – processing – microstructure - mechanical properties - performance relationships in polycrystalline and single crystal Ni-base superalloys. Prof. Tin is an internationally recognized expert in the field of superalloy creep, fatigue, oxidation and solidification. For many of these research activities, has collaborated extensively with industrial researchers at GE Aircraft Engines, GE Global Research Center, Rolls-Royce, Special Metals, Wyman Gordon, Firth-Rixson, PCC Airfoils, Caterpillar, Howmet and the Air Force Research Laboratory. Professor Tin serves on the Editorial Committee for Metallurgical and Materials Transactions A, Materials Science and Technology A and was the recipient of the 2004 Rolls-Royce Mark Shipton Patent Award, the 2006 IOM3 Cook/Ablett Award and the 2007 ASM Marcus A Grossmann Award. He has also served as the Chair of the TMS High Temperature Alloys Committee and is currently Chair of the 2020 International Conference on Superalloys. Prof. Tin has five patent applications and authored over 100 manuscripts in referred journals and conference proceedings.