FeCrAlY and TiN coatings on T91 steel after irradiation with 72 MeV protons in flowing LBE

In this work, T91 steel with FeCrAlY and TiN coatings was irradiated with 72 MeV protons in flowing liquid lead–bismuth eutectic (LBE) at temperatures up to about 400 °C for about 900 h. The maximum irradiation dose was 2.5 dpa for the FeCrAlY coating and 1.8 dpa for the TiN coating. SEM and EPMA analyses on as irradiated samples showed that no surface damages were induced by LBE corrosion and both coatings were stable under the present test condition. SEM observations on the samples after bending to various levels demonstrated the FeCrAlY coating was more ductile than the TiN coating. The embrittlement effect induced by the irradiation resulted in large cracks in the irradiated FeCrAlY coating and delaminating of the irradiated TiN coating after bended to surface strain above ∼3%.