Microstructural evolution of a silicon carbide-carbon coated nanostructured ferritic alloy composite during in-situ Kr ion irradiation at 300℃ 450℃

摘要

This work focuses on irradiation behaviors of a novel silicon carbide and carbon coated nanostructured ferritic alloy(SiC-C@NFA)composite for potential applications as a cladding and structural material for next generation nuclear reactors.The SiC-C@NFA samples were irradiated with 1 MeV Kr ions up to 10 dpa at 300 and 4500 C.Microstructures and defect evolution were studied in-situ at the IVEM-Tandem facility at Argonne National Laboratory.The effects of ion irradiation on various phases such asα-ferrite matrix,(Fe,Cr)_(7)C_(3),and(Ti,W)C precipitates were evaluated.Theα-ferrite matrix showed a continuous increase in dislocation density along with spatial ordering of dislocation loops(or loop strings)at>5 dpa.The size of the dislocation loops at 450℃was larger than that at 300℃.The nucleation and growth of new(Ti,W)C precipitates inα-ferrite grains were enhanced with the ion dose at 450℃.This study provides new insight into the irradiation resistance of the SiC-C@NFA system.