About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Fracture and Deformation Across Length Scales: Celebrating the Legacy of William Gerberich
|
| Presentation Title |
Yield points during indentation: what one small step can tell you |
| Author(s) |
David F. Bahr, Jia-Huei Tien , Morgan Chamberlain |
| On-Site Speaker (Planned) |
David F. Bahr |
| Abstract Scope |
Source nucleation or activation is often invoked for “odd” indentation behavior (sudden changes in load or depth during an indentation test). Instrumented indentation greatly accelerated the ability to study these phenomena in a quantified manner and W.W. Gerberich’s work led to advances in identifying a variety of mechanisms which could manifest as onset of plasticity in metals and semiconductors. This presentation will cover quantitative measurements of the yield distributions in metals and molecular crystals, and identify conditions than determine if the experiment is activating an existing dislocation source or nucleating a new dislocation. The yield behavior is not tied to stacking fault energy in several metallic systems. An example of where solid solution strengthening in Sn makes a material harder, but the impurity has little effect on the nucleation of dislocations, will be described to demonstrate the need to isolate the differences between making dislocations and moving existing dislocations. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, |