Interaction between point defects and solute atoms under irradiation

Recent works on the irradiation effects on reactor materials are reviewed with emphasis on the interaction between irradiation point defects and solute atoms and the phenomina of radiation-induced segregation. In the first part, the general behavior of the radiation-induced point defects is explained with the examples of the point defects in pure metal and the growth of dislocation loops. The interaction between defects and solute atoms is explained for the case of dilute alloy, and the trapping effect of solute atoms and the formation and diffusion of the complex are the main themes. In the third part, the non-equilibrium status induced by radiation is discussed. The effect of the size of solute atoms on segregation is discussed in detail on the basis of the irradiation experiment with electron beam and C+ ion bombardment. The process of segregation is considered in two ways; segregation accompanying the movement of point defects, and segregation due to the formation and movement of the complex. Finally, the influence of segregation on the formation and growth of voids are discussed. (Aoki, K.)