About this Abstract |
| Meeting |
TMS Specialty Congress 2026
|
| Symposium
|
4th World Congress on High Entropy Alloys (HEA 2026)
|
| Presentation Title |
The Negative Correlation Between Twinning Stress and Stacking Fault Energy in Single Crystals of CrCoNi Alloys |
| Author(s) |
Le Li, Zhenghao Chen, Kyosuke Kishida, Haruyuki Inui |
| On-Site Speaker (Planned) |
Le Li |
| Abstract Scope |
Despite the on-going debate of the twinning mechanisms in FCC metals and alloys, there is a consensus stacking fault energy (SFE) plays a central role: low SFE promotes wider separation of Shockley partials, facilitating the formation of stacking faults and lowering the energy barrier for twin nucleation. A positive correlation between SFE and twinning stress seems to be well-established in FCC metals and alloys. In recent years, however, a negative twinning stress-SFE correlation is obtained from polycrystals of some high-entropy alloy of the Cr-Mn-Fe-Co-Ni system. These conflicting literature results are considered to be mainly due to the absence of a convincing experimental measurement of twinning stress. In this study, we investigate the SFE and tensile deformation behavior of single crystals of four Cr-Co-Ni alloys with varying compositions. TEM observations reveal the interaction between the deformation twinning and forest (primary) dislocations, which affects the twinning shear stress-SFE correlation in these alloys. |
| Proceedings Inclusion? |
Undecided |