Journal of Materials Research and Technology (Nov 2024)

Accelerated formation of M2C carbides by proton irradiation inhibits molten salt corrosion in Ni-based alloy

  • Weichi Ji,
  • Zhenbo Zhu,
  • Hefei Huang,
  • Cheng Li,
  • Guanhong Lei,
  • Yan Li

Journal volume & issue
Vol. 33
pp. 742 – 748

Abstract

Read online

The effect of displacement damage on the corrosion behavior in a molten FLiBe salt environment was investigated. The element distribution and microstructure around the grain boundaries (GBs) after corrosion were characterized. The results show a decrease in corrosion thickness with increasing irradiation dose and the presence of intergranular corrosion. Nanoscales M2C carbides were observed to be distributed, with a denser and thicker distribution in samples with higher irradiation doses. Their distribution depth is related to the Cr depletion region, inhibiting Cr diffusion toward the GBs and surface. Furthermore, the nucleation mechanism of M2C carbides along the GBs and in irradiated regions was revealed, attributed to the combined effects of thermal influences, element preferential dissolution due to corrosion, and irradiation-induced segregation.

Keywords