| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Advanced Characterization of Materials for Nuclear, Radiation, and Extreme Environments V
|
| Presentation Title |
Atomic-Scale Hidden Point-Defect Complexes Induce Ultrahigh Irradiation Hardening in BCC Metals |
| Author(s) |
Weizhong Han |
| On-Site Speaker (Planned) |
Weizhong Han |
| Abstract Scope |
Body-centered cubic tungsten displays exceptionally high strength in extreme of temperature and radiation environments and is considered a promising plasma facing material for fusion nuclear reactors. Unlike other metals, it experiences substantial irradiation hardening, which limits service life and presents safety concerns. The origin of ultrahigh irradiation hardening in tungsten cannot be well explained by conventional strengthening theories. Here, we demonstrate that irradiation leads to near three-fold increases in strength in tungsten, while the usual defects that are generated only contribute less than one third of the hardening. We reveal that a large fraction of atomic-scale hidden He-vacancy complexes are frozen in the lattice due to very high vacancy migration energies, which cause the abnormal irradiation hardening. This unique hardening mechanism also cause the ultrahigh irradiation hardening in niobium. Refs. Nano Lett-21 (2021) 5798 and Acta Mater- 226 (2022) 117656. |