Analysis of Effects in a Low activation Ferritic/Martensitic Steel by High energy Heavy-ion Irradiation

Key words: 
• Ferritic/Martensitic steel /
• highenergy heavy ion /
• radiation damage /
• void /
• swelling

Abstract: Lowactivation Ferritic/Martensitic steels are a kind of important structural materials candidate to the application in advanced nuclear energy systems. Possible degradation of properties and even failure in the condition of hightemperature and high helium production due to energetic neutron irradiation in a fusion reactor is a major concern with the application of this kind of materials. In the present work microstructural evolution in a 9Cr Ferritic/Martensitic steel (T92B) irradiated with 122 MeV  20Ne ions at temperatures between 0.3—0.5 Tm (Tm is the melting point of the material) was investigated with transmission electron microscopy. High concentration voids were observed in the specimens irradiated at high temperatures when the displacement damage dose and Ne concentration exceed a certain level. Preferential formation of voids at lathboundaries and other grainboundaries was found. The data of void swellings in 9Cr ferritic/martensitic steels irradiated in different conditions (such as with Heions, Neions, Fe/He dual beams, fast neutrons, Niions etc.) were compiled and analyzed based on a classic model of helium bubble formation, and bubble to void transition.