Research progress in multiprincipal element alloys for nuclear structure materials on irradiation damage

The development of nuclear reactor structural materials with excellent comprehensive performance is the basis of nuclear energy development, and it is one of the difficulties that have long restricted the promotion of nuclear energy. Multiprincipal element alloys (MEAs) have been recognized as candidate materials for advanced reactor structural materials due to their good irradiation resistance and mechanical properties, which has expanded a broad space for the design of new radiation-resistant materials. In recent years, the research on the irradiation damage of multiprincipal element alloys has tried to reveal the influence of some factors and characteristics of multiprincipal element alloys on the formation and evolution of defects in the irradiation process. For example, the type, number and concentration of alloying elements, lattice distortion, chemical short range order, etc. Although some existing research results show that the above factors can improve the resistance of multiprincipal element alloys to irradiation damage, under different irradiation conditions, the influence mechanism of the above factors on the formation and evolution of defects in multiprincipal element alloys is quite different, and it is difficult to draw generalization conclusions. Focusing on the four aspects of irradiation swelling, helium bubble formation, irradiation-induced element segregation and phase transition, irradiation hardening of FCC and BCC systems.The research progress of multiprincipal element alloys in irradiation damage in recent years was reviewed, the mechanism of action of multiprincipal element alloys to improve radiation resistance was summarized.And based on this, the future research directions for multiprincipal element alloys used in nuclear power structures were prospected, including tuning short-range order, high-entropy ceramics, additive manufacturing technology, accelerating development of new materials by integrating high-throughput computing with machine learning, etc. Finally, it is pointed out that new radiation-resistance MEAs must be designed based on the actual environment of material service from the perspective of composition design.