About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
30 Years of Nanoindentation with the Oliver-Pharr Method and Beyond
|
Presentation Title |
Your Default Load Function May be Working Against You and What To Do About It |
Author(s) |
Michael Maughan, Evan Allen, Marzyeh Moradi |
On-Site Speaker (Planned) |
Michael Maughan |
Abstract Scope |
Nanoindentation is commonly conducted using simple load functions with a single loading cycle. We investigate in a variety of pure metals a strict implementation of the Oliver-Pharr four-cycle load function and longer-hold load function for collecting indentation data and compare these to simple triangle load functions as commonly applied. The choice of load function is shown to impact the magnitude of hardness and indentation size effect (ISE) through low-temperature creep. In some cases, as much as 30% difference in hardness is observed. Nanoindentation testing strategies for best comparability between indentation depths are discussed in terms of microstructure mechanisms and practical testing techniques. A mechanism to account for the depth change based on Cottrell’s exhaustion creep is presented. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Thin Films and Interfaces, Nanotechnology |