Keywords: 
• 氦 /
• 氘 /
• 辐照损伤 /
• 位错环

Abstract: Productions of transmute elements (hydrogen and helium) have great influences on the resistance to irradiation damage in struc-tural materials for fusion reactor. The evolution of irradiation damage in bcc iron is investigated with ion implantation and electron irradiation. Pure iron implanted by He+ or D+ ions at room temperature are aged at 500 ?C for 1 h, then irradiated by electrons under high voltage electron microscope. The results show that interstitial loops (i-loop) and vacancy loops (v-loop) are formed in He+-implanted iron and D+-implanted iron respectively. Under electron irradiation, due to the absorption of interstitials atom, i-loop grows up while v-loop shrinks. According to the rate of variation of dislocation loop, v-loop absorbs more interstitial atoms, i.e., the dislocation bias of D+-implanted iron is larger than that of He+-implanted iron, which means that the v-loop has the more contribu-tions to irradiation swelling than i-loop. The causes of the different natures of dislocation loops formed in D+-implanted iron and He+-implanted iron are analyzed by the structures of He-V and D-V complexes.