Kim, Sangeun Ahn, Minkyu Park, Jinwoo Yu, Gyeongsik Kim, Jinhyuk Jin, Hyung-Ha Lee, Chang-hoon Yu, Byung-Yong Lim, Weon Cheol Shin, Chansun 2024-08-22T08:30:24Z 2024-08-22T08:30:24Z 2024-08-22 2024-06 2352-1791 https://pubs.kist.re.kr/handle/201004/150472 This study explores the effects of Fe ion irradiation and helium implantation on the mechanical and micro- structural behaviors of K-RAFM steels. Through micropillar compression tests, we observed irradiation hardening, which manifested as an increase in strength and a decrease in strain bursts in the irradiated specimens. This change in deformation behavior indicates the impact of radiation-induced defects on dislocation dynamics. Helium implantation resulted in the formation of surface steps and, as shown by nanoindentation mapping, led to a localized increase in hardness, highlighting the significant influence of helium on mechanical properties. Microstructural examination revealed the steel's tempered martensitic structure and pointed to the importance of M 23 C 6 and MX precipitates in modulating the effects of irradiation. Notably, K-RAFM steels showed a diminished extent of irradiation hardening, which can be attributed to the higher fraction of MX precipitates serving as effective trapping sites for point defects. Understanding how microstructural features influence mechanical performance in K-RAFM steels assists in steering the creation of materials tailored to improve radiation resistance in nuclear environments. English Elsevier Limited Mechanical and helium swelling responses of K-RAFM steels to Fe ion irradiation and helium implantation Article 10.1016/j.nme.2024.101652 1 Nuclear Materials and Energy, v.39 Nuclear Materials and Energy 39 Y scie scopus 001288963300001 2-s2.0-85190133818 Nuclear Science & Technology Nuclear Science & Technology Article ACTIVATION FERRITIC/MARTENSITIC STEEL TWINNING-INDUCED PLASTICITY FERRITIC-MARTENSITIC STEEL RESEARCH-AND-DEVELOPMENT MICROPILLAR COMPRESSION BUBBLE FORMATION MICROSTRUCTURE DEFORMATION STRENGTH TENSILE RAFM steels Irradiation hardening Helium swelling