About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Mechanical Response of Materials Investigated through Novel In-situ Experiments and Modeling
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Presentation Title |
Numerical Examination of the Oliver-Pharr Method for Nanoindentation of Shape Memory Alloys |
Author(s) |
Xuesong Gao, Daniel Hong, Harshad Paranjape, Wei Zhang, Peter Anderson |
On-Site Speaker (Planned) |
Xuesong Gao |
Abstract Scope |
The Oliver-Pharr (O-P) method has been widely used to study mechanical properties for conventional materials. It provides convenient procedures to determine the relevant parameters (i.e. correction factor, contact stiffness and contact area) for extracting mechanical properties. When applying the O-P method to shape memory alloys (SMAs), the applicability of the procedures and the interpretation of the measured modulus are not well-known. This work applies the O-P method to SMAs in sharp indentations by finite element modeling. It’s found that the correction factor is not constant but a linear function of the transformation strain. The contact stiffness can be obtained by fitting the initial elastic portion of the unloading curve. The subsequent portion convoluted by the reverse transformation produces errors. The area function is suitable to calculate contact area within 5% error for regular SMAs. The measured modulus is a phase-composition related harmonic average of moduli of austenite and martensite phases. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, Phase Transformations, Mechanical Properties |