Evolution of vacancy-type defects and hardening behaviors of T91 induced by 1.625 MeV Fe-ions at different temperatures

Microstructure evolution of T91 steel after heavy ion irradiation at 550 °C*

“…The T91 steel showed a higher ratio of edge dislocations. Zhu et al [15] studied T91 steel irradiated by 1.625-MeV Fe ions to the fluence of 2.5×10 15 ions/cm 2 from room temperature (RT) to 550 ∘ C and found that the sample irradiated at RT possessed the largest concentration of vacancytype defects. At higher temperatures, the vacancy-type defects concentrations were in an increasing trend of 550 ∘ C, 300 ∘ C, 450 ∘ C. Zhu et al [16] investigated temperature-dependent surface modification induced in T91 steel irradiated by 3.25-MeV Fe-ions to fluence of 1.7×10 16 ions/cm 2 at room temperature, 300 ∘ C and 450 ∘ C, respectively.…”

“…The irradiated microstructure included primarily dislocation loops, in which the average size and density is a function of irradiation dose. Liu et al [18] have studied the microstructural evolution of ferritic/martensitic steel T91 under 1-MeV Kr ion irradiation up to 4.2×10 15 ions/cm 2 at 300 ∘ C, 400 ∘ C, and 500 ∘ C. At 300 ∘ C, grown-in defects are strongly modified by black dot loops, and dislocation networks together with black-dot loops were observed after irradiation. At 400 ∘ C and 500 ∘ C, grown-in defects are only partially modified by dislocation loops; isolated loops and dislocation segments were commonly found after irradiation.…”