| About this Abstract |
| Meeting |
13th International Conference on the Technology of Plasticity (ICTP 2021)
|
| Symposium
|
13th International Conference on the Technology of Plasticity (ICTP 2021)
|
| Presentation Title |
A Predictive Strain-gradient Treatment with No Undetermined Constants or Length Scales |
| Author(s) |
G. Zhou, W.J. Chung, Eric R. Homer, David T. Fullwood, M. G. Lee, J. H. Kim, H. Lim, Hussein M. Zbib, Robert H. Wagoner |
| On-Site Speaker (Planned) |
Robert H. Wagoner |
| Abstract Scope |
A crystal-plasticity FE material model (“SD” model) was previously shown to predict, quantitatively and without arbitrary fit constants, the mechanical behavior of metal polycrystals. Confirmed quantitative predictions were achieved for the Hall-Petch Effect, the Bauschinger Effect, and Pre-Yield Nonlinear stress-strain behavior. The last of these was predicted inherently by the SD model before its existence was known experimentally, thus emphasizing its predictive nature. The SD model incorporated two simplifying fundamental assumptions: 1) only edge dislocations were assumed to be active, and 2) only like-dislocation interactions were considered within a single slip system and grain. Separately, two approximate treatments were adopted to achieve numerical stability: 1) column element-sampling (i.e. only elements along a slip direction to integrate the internal back stress), and 2) implementation of the back stress as a friction stress (opposite in sign and not exceeding the applied local stress).The resulting new General Mesoscale (“GM”) model eliminaes both of the fundamental SD assumptions and both of the approximate SD treatment without invoking any arbitrary parameters. The new GM model retains the predictive nature of SD while permitting solutions for much more general problems and materials. Results for the two methods are compared and a series of numerical tests presented. |
| Proceedings Inclusion? |
Definite: At-meeting proceedings |