Study On The Evolution Of Irradiation Defect And Irradiation Resistance Of Binary Nickel Base Alloys

Nickel based alloys has excellent oxidation resistance and high temperature mechanical properties,and it is an important candidate structural material for molten salt reactor.Its most common solid solution elements are Cr and Mo.Cr can improve the corrosion resistance of the alloy,and Mo mainly plays the role of strengthening.In the service process of molten salt reactor,its structural material will inevitably be irradiated by high dose neutron.Therefore,domestic and foreign scholars have done a lot of research on the radiation effect of nickel based alloys.However,there are few reports about the effect of solid solution elements on the properties of nickel based alloys under irradiation.The atomic size of Cr is quite different Mo,and its solid solution alloys will show different irradiation results under irradiation.In this paper,Ni、Ni-Cr、Ni-Mo are used as the prototype to study the irradiation effect of solid solution elements on nickel based alloys.Ni,Ni-10%wt.Cr and Ni-10%wt.Mo are irradiated by 400 keV Ne ions at room temperature、300 ℃、500 ℃,respectively.The results show that,compared with room temperature irradiation,the defect size of Ni increases at 300 ℃,but the defect size of Ni-10%wt.Cr and Ni-10%wt.Mo does not change greatly.Compared with the irradiation at 300 ℃,when the irradiation temperature is 500 ℃,the defect size of Ni increases 18 times,the defect size of Ni-10%wt.Cr increases 6 times,and the defect size of Ni-10%wt.Mo increases 6 times.This shows that Cr and Mo can effectively inhibit the growth of Ni defect under high temperature irradiation.Furthermore,by irradiating Ni,Ni-20%wt.Cr,Ni-20%wt.Mo with 50 keV Ne ions,it is found that Cr has a strong limiting effect on the growth of defect,and Mo has inhibiting effect on the formation of defect.Ni,Ni-20%wt.Cr and Ni-20%wt.Mo are irradiated by 2 MeV Ne ions.The results show that the lattice of(111)surface of Ni,Ni-20%wt.Cr and Ni-20%wt.Mo does not have obvious distortion after irradiation,and the hardening of Ni-20%wt.Cr and Ni-20%wt.Mo alloys approached saturation,but there is no tendency of hardening saturation in Ni.Finally,the results of Makin-Minter model and transmission electron microscope further revealed that the inhibition ability of Mo to defect is higher than that of Cr.In this paper,Ni,Ni-Cr,Ni-Mo are irradiated by Ne ions,and the effect of Cr and Mo on the defect evolution and radiation resistance of Ni based alloys are clarified,which has certain reference significance for subsequent design and optimization of Ni based alloys.