About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Materials Science and Engineering of Materials in Nuclear Reactors
|
Presentation Title |
The Effect of Minor Additives on Radiation Induced Segregation in Austenitic Steel Alloys |
Author(s) |
Yongfeng Zhang, Anus Manzoor , Dilpuneet Aidhy, Miao Song , Xiaoyuan Lou, lingfeng He |
On-Site Speaker (Planned) |
Yongfeng Zhang |
Abstract Scope |
Radiation induced segregation (RIS) such as Cr depletion at grain boundaries can facilitate stress corrosion cracking in stainless steels. It has been shown experimentally that additives that trap point defects can effectively mitigate Cr depletion. However, such mitigation may just be temporary at low irradiation doses, as suggested by other experiments. To help understand the experimental results and select beneficial additives, a lattice kinetic Monte Carlo model is developed and parameterized by first principle calculations for RIS in austenitic FeNiCr alloys. It’s shown that additives that strongly bind with vacancies, such as Hf, Y and Zr, can indeed delay Cr depletion. However, these additives themselves are subject to radiation induced precipitation, losing the mitigating effect at high irradiation doses. This explains the inconsistency in previous experiments. Such precipitation is kinetically driven and can occur even in under-saturated alloys. The model and the results will help select additives for mitigating RIS. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |