In lead-cooled fast reactor(LFR)systems,the liquid lead-bismuth eutectic(LBE)coolant provides a cor-rosive environment that damages the steel components during high-temperature operation.This study investigated the mi...In lead-cooled fast reactor(LFR)systems,the liquid lead-bismuth eutectic(LBE)coolant provides a cor-rosive environment that damages the steel components during high-temperature operation.This study investigated the microstructural deterioration of 9Cr ferritic/martensitic(F/M)steel under thermal aging at 550℃for 2,000,10,000,or 20,000 h and its effect on oxidation corrosion in an LBE environment using multiscale characterization techniques.The results indicated that the thickness of the internal oxidation zone(IOZ)increased significantly with extended thermal aging,whereas that of the spinel layer remained relatively constant.The abundant subgrain boundaries that emerged during extensive thermal aging facil-itated Fe diffusion,and the enlarged Cr-rich M23C6 carbides contributed to the formation of preferential oxidation regions,accelerating IOZ layer growth.The spinel layer formed from the IOZ was influenced by microstructural defects within the IOZ.A theoretical model describing the accelerated oxide layer growth due to thermal aging was developed.These findings support the advancement of LFR technology.展开更多
基金supported by the Natural Science Foundation of Shandong Province with grant No.ZR2023ME196the Science and Technology Support Plan for Young Innovation of Colleges and Universities of Shandong Province with grant No.2022KJ273+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences with grant No.2017486the Patent Navigation Project of Shandong Province with grant No.D202327.
文摘In lead-cooled fast reactor(LFR)systems,the liquid lead-bismuth eutectic(LBE)coolant provides a cor-rosive environment that damages the steel components during high-temperature operation.This study investigated the microstructural deterioration of 9Cr ferritic/martensitic(F/M)steel under thermal aging at 550℃for 2,000,10,000,or 20,000 h and its effect on oxidation corrosion in an LBE environment using multiscale characterization techniques.The results indicated that the thickness of the internal oxidation zone(IOZ)increased significantly with extended thermal aging,whereas that of the spinel layer remained relatively constant.The abundant subgrain boundaries that emerged during extensive thermal aging facil-itated Fe diffusion,and the enlarged Cr-rich M23C6 carbides contributed to the formation of preferential oxidation regions,accelerating IOZ layer growth.The spinel layer formed from the IOZ was influenced by microstructural defects within the IOZ.A theoretical model describing the accelerated oxide layer growth due to thermal aging was developed.These findings support the advancement of LFR technology.
