| In order to adapt to the increasingly harsh working conditions of the new generation of advanced nuclear energy system,such as the rising operating temperature and neutron flux,the development of reactor structural materials with higher safety has become an urgent problem to be solved in the development of advanced nuclear energy technology.The new anti-irradiation materials which based on the theory of"interface self-repairing"are the key research directions at home and abroad at present.In this paper,jet electrodeposition and radiation damage resistance of Ni-based graphene composites with metal/graphene nano-interface were studied.The main research contents and results are as follow:(1)Based on the theory of composite electrodeposition,a jet electrodeposition equipment for preparing metal graphene composites was designed and built,which includes key components such as plating circulation system,control transmission system,ultrasonic heating system.And the equipment parameters affecting the jet electrodeposition process,such as bath flow rate and current density,were optimized.The results show that the fastest jet electrodeposition rate can be achieved when the bath flow rate is 400 L/H and the current density is 100 A/dm~2.(2)Changing the concentration of graphene oxide(GO),nickel-based graphene composites were prepared by jet electrodeposition equipment,and the effects of electrodeposition process on the structure and the properties of the composites were studied.It was found that the concentration of graphene oxide(GO)in the bath determined the distribution of graphene and the structure of nickel matrix.When GO concentration is 0.5 g/L,graphene is uniformly dispersed with strong interfacial bonding force.The surface of the coating is smooth and has good mechanical and corrosion resistance.Therefore,jet electrodeposition technology can alleviate the problems that restrict the development of metal graphene composites,such as poor dispersion of graphene,failure of integrity and poor interface bonding,so as to realize the initial assumption of the structure of the new interface radiation resistant material of metal graphene.(3)The helium ion irradiation experiments of pure nickel and nickel-based graphene composites prepared by jet electrodeposition were carried out to study the relationship between irradiation micro-defects and mechanical properties.It was found that after irradiation,many helium bubbles with a size of about 1 nm were produced in pure nickel,which resulted in obvious radiation swelling and radiation hardening,with a hardening degree of 54.12%.In nickel-based graphene composites,a large number of graphene Nano-interfaces can act as"traps"to absorb irradiation defects,which greatly reduces the irradiation defects in the material,and the degree of irradiation hardening is only 11.05%.At the same time,there is no obvious phenomenon of lattice swelling and graphene structure damage.It is proved that the large number of interfaces generated by uniformly dispersed GO phase can effectively improve the damage properties of materials irradiated at room temperature.After high temperature annealing,irradiation defects such as vacancies and helium bubbles migrate and diffuse to form larger defects,or are absorbed by the interface,which greatly reduces the density of irradiation defects in the material,thus resulting in irradiation softening.Nickel-based graphene nanocomposites were prepared by jet electrodeposition.It effectively alleviates the problems of graphene agglomeration and interface bonding instability which often occur in the preparation of metal graphene composites.This material not only has the advantages of uniform internal composition,smooth surface,greatly improved mechanical properties and corrosion resistance,but also has good radiation resistance at helium ion irradiation environment.This provides an important experimental reference for the research and application of new anti-irradiation materials. |
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