Helium irradiation-induced segregation and mechanical response in China low activation martensitic (CLAM) steel

The China Low Activation Martensitic (CLAM) steel was irradiated by high energy helium ions under different ion doses, the microstructure evolution was studied by using a transmission electron microscope (TEM) and Energy Dispersive Spectrometer (EDS) mapping. The mechanical response of this material before and after irradiation was investigated under micropillar compression test. The results indicate that radiation leads to Cr segregation at the grain boundary and facilitates the growth of M23C6 precipitate. The pillar compression demonstrate that the strength of the CLAM steel increased due to irradiationinduced defects strengthening. The deformed micropillar is analyzed by TEM observation, indicating the cracks nucleated around the M23C6 precipitate. Furthermore, the effect of the M23C6 on mechanical behavior is discussed.(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This study investigates the microstructure evolution and mechanical response of CLAM steel under high energy helium ion irradiation. The results show that radiation causes chromium segregation and promotes the growth of M23C6 precipitates. The irradiation-induced defects strengthen the strength of the steel.