The 178th Structural Materials Seminar: Associate Prof. Paraskevas Kontis (Norwegian University of Science and Technology)
On November 05, 2025, Associate Prof. Paraskevas Kontis (Department of Materials Science and Engineering, Faculty of Natural Sciences, Norwegian University of Science and Technology (NTNU)) gave a lecture at NIMS as the 178th Structural Materials Seminar.
Prof. Paraskevas Kontis (Fifth from the right)
- Date and Time
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Wednesday, Nov. 5, 2025. 13:30～14:30
- Location
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Conference Room, 5th Floor, Advanced Structural Materials Building, NIMS Sengen Site
- Title
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Understanding deformation mechanisms in superalloys through partitioning of solutes at crystal defects,
- Speaker
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Associate Prof. Paraskevas Kontis, Department of Materials Science and Engineering, Faculty of Natural Sciences,
Norwegian University of Science and Technology (NTNU),
Abstract
Solutes interact with crystal defects, e.g. dislocations and stacking faults, during deformation. These interactions result in microstructural and compositional alterations that control the high-temperature mechanical performance of superalloys. Recent technological breakthroughs in high-resolution characterization have enabled compositional imaging of solutes at the near-atomic scale, providing new insights into such interactions. Based on these findings, case studies on understanding deformation mechanisms in superalloys through partitioning of solutes at crystal defects will be presented. In particular, the role of oxidized carbides in acting as crack initiation sites by facilitating localized microstructural and compositional alterations in polycrystalline superalloys will be presented. In addition, the formation of undesirable precipitates controlling crack initiation during very high-cycled fatigue and out-of-phase thermomechanical fatigue of single crystal superalloys will be presented.