| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Mechanical Behavior at the Nanoscale V
|
| Presentation Title |
Fracture Properties of Ultrafinegrain Chromium at RT: Dislocations Processes and Toughening Mechanisms |
| Author(s) |
Inas Issa, Anton Hohenwarter, Reinhard Fritz, Daniel Kiener |
| On-Site Speaker (Planned) |
Inas Issa |
| Abstract Scope |
Scale-bridging fracture experiments on ultrafine-grained chromium (UFG, Cr) are performed at different length scales, starting from macroscale over microscale (in situ SEM) down to nanoscale (in situ TEM). A quantitative assessment of the fracture toughness yields ∼3 MPa.m1/2 in the frame of LEFM.
In situ TEM tests reveal explicitly the occurrence of dislocation emission processes and related crack tip blunting serving as toughening mechanisms before intercrystalline fracture in UFG bcc metals.
In relation to coarse-grained Cr, in situ TEM tests demonstrate the importance of strengthening grain boundaries (GBs) as promising strategy in promoting further ductility and toughening in UFG bcc metals. By adding adhesion improving impurities such as Carbon or Boron, we modify the atomistic GBs configuration in front of the notch and will present how local segregation affects GBs cohesion and fracture toughness. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |