Effect of Au ion irradiation on microstructure, mechanical, and lead‐bismuth eutectic corrosion properties of Cr/ZrO₂ coatings

The effect of ion irradiation on the microstructure, mechanical, and corrosion properties of Cr/ZrO 2 coating was investigated. The monoclinic to tetragonal phase transition is observed under heavy ion irradiation, and the tetragonal phase is stabilized by the irradiation‐induced defect clusters. With increasing irradiation fluence, grain growth, and irradiation‐induced hardening effects are observed. After lead‐bismuth eutectic (LBE) corrosion at 650°C for 1000 h, the irradiated coatings can still maintain structural integrity and protect the substrate from lead/bismuth corrosion. However, in contrast to the unirradiated coating, the irradiation‐induced defects provide a channel for the rapid inward diffusion of oxygen atoms from the LBE, leading to the formation of a thicker Cr‐rich oxide layer beneath the ZrO 2 coating. This study also provides insight into how irradiation‐induced microstructural changes affect zirconia's properties as a corrosion protection layer.