A time-dependent Ginzburg-Landau (TDGL) model for time-evolution of local degree of order S and local concentration X was employed in studying dissolution dynamics of ordered precipitates under irradiation with energetic particles. In the simulation, the irradiation effect was taken into account as random formation of small zones, in which disordering and atom mixing occur momentarily. The process depends sensitively on dose rate of irradiation. In the case of a high dose rate, the precipitates disappear in two separate steps. The ordered structure is quickly destroyed and then the precipitates dissolve into the matrix of a disordered phase. In comparison, the disordering and the dissolution proceed at the same time when the dose rate is significantly low. The precipitates with locally disordered regions shrink with time. Fine ordered precipitates are newly formed in the matrix in the latter case. It is suggested that the moderate irradiation with a low dose rate is available for refinement of ordered precipitates.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- General Materials Science
- Nuclear Energy and Engineering