About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
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Microstructure-Sensitive Design and Advanced Characterization: An MPMD/SMD Symposium Honoring David T. Fullwood
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| Presentation Title |
Grain Boundary Effects on Nanoindentation response of Tantalum Bicrystals: Experiments and Coupled Crystal Plasticity-Cohesive Zone Element Modeling |
| Author(s) |
Sajjad Izadpanah, Olajesu F. Olanrewaju, Kevin Jacob, Siddhartha Pathak, Curt A. Bronkhorst, Marko Knezevic |
| On-Site Speaker (Planned) |
Sajjad Izadpanah |
| Abstract Scope |
Interactions between grain boundaries (GBs) and dislocations during nanoindentation — whereby GBs act either as barriers that strengthen the material or as sinks that promote localized damage and weakening — remains poorly understood. This study develops a crystal plasticity finite element (CPFE) framework including statistically stored and geometrically necessary dislocations (GNDs) and cohesive zone elements (CZEs) to investigate these interactions during nanoindentation of tantalum bicrystals. Yield stress and initial hardening responses of tantalum bicrystals are simulated as a function of the distance from GBs and compared with corresponding experiments. Simulations without GND accumulation and CZE, with GND accumulation at GBs, and with both isolated the individual and combined contributions of GNDs and CZE on the indentation yield and initial hardening responses. The competing roles of individual GBs as barriers or damage sites in tantalum under contact loading are interpreted using the model and experiments. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Other, Other, Other |