Effects of Helium on Behavior of Point Defect Produced by Irradiation in Low Activation Fe-Cr-Mn(W,V) Alloys
He对低活性Fe-Cr-Mn(W,V)合金辐照产生点缺陷行为的影响

In order to investigate the effects of helium on the excess point defects and secondary defects processes in low activation Fe-Cr-Mn(W, V) alloys during electron beam and electron-He+ ion dual beam irradiation, the in situ observation was carried out using a high voltage electron microscope connected with an ion accelerator. The experiment result indicates that the interaction between helium and point defect clusters formed in the early stage of irradiation affected the secondary defects (dislocation, dislocation loop and void) formation. The helium enhances the increase in dislocation density and void nucleation site obviously. As a result, the void swelling in Fe-Cr-Mn(W, V) alloy was enhanced. The mechanism of interaction between helium and point defects produced by irradiation was also discussed.