|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||High Entropy Alloys VI
||Unusual Interstitial Strengthening of High-entropy Alloys Evading the Strength-ductility Trade-off
||Zhifeng Lei, Xiongjun Liu, Shudao Wang, Hui Wang, Yuan Wu, Paraskevas Kontis, Baptiste Gault, Dierk Raabe, Houwen Chen, Tai-Gang Nieh, Zhaoping Lu
|On-Site Speaker (Planned)
Conventional wisdom holds that interstitial strengthening suffers from the undesirable consequence that a substantial increase in strength also causes reduced ductility (i.e., embrittle the material), an effect referred to as the strength-ductility trade-off. Herein we report a family of single-phase refractory high-entropy alloys (HEAs) with addition of a high amount of oxygen (~ 2.0 at. %) which possess ~ 1.2 GPa tensile yield strength and large plasticity of 28.5 % at ambient temperature. In contrast to conventional wisdom, we found that both strength and ductility were greatly improved by doping appropriate concentration of oxygen, breaking the paradigm of strength-ductility trade-off. Such evasion attributes to the deformation-induced atomic segregation which results in the planar-to-wavy slip transition of dislocation glide and dislocation pileups. These observations challenge the traditional view of interstitial strengthening in metallic materials and provide insights into the development of high-performance metals and alloys with new regimes of property-performance space.
||Planned: Supplemental Proceedings volume