About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
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Mechanical Behavior at the Nanoscale VII
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Presentation Title |
A Unified Approach to Quantify the Indentation Size Effect |
Author(s) |
Harita Seekala, Vikram Balaji, L. Rama Krishna, Hariharan Krishnaswamy, P. Sudharshan Phani |
On-Site Speaker (Planned) |
Harita Seekala |
Abstract Scope |
The seminal work of Nix & Gao, laid the foundation for quantifying indentation size effect (ISE). In this work, a unified approach to quantify ISE is presented, wherein the effects of material, geometry and other coupled parameters on ISE are incorporated to derive a simple analytical model. The analytical model is based on stress superposition resulting from microstructural and geometric features having different length scales. To assess the model, Finite Element Analysis (FEA) of indentation is also performed. The FE model includes strain gradient effects and dislocation density evolution based on the well-known Kocks-Mecking-Estrin (KME) model. The analytical model predictions and the FEA results are validated by uniaxial compression and indentation tests on nickel and calcium fluoride. Insights on the relative contributions of the various microstructural and geometric parameters will be presented. In addition, the well-known concept of equivalent strain during indentation will be revisited in the context of ISE. |
Proceedings Inclusion? |
Planned: |