ANNIHILATION PROCESS OF PERIODIC ANTIPHASE BOUNDARIES IN CU3PT STUDIED WITH TIME-DEPENDENT GINZBURG-LANDAU MODEL

Kinetics of the annihilation process of periodic antiphase boundaries in a Cu3Pt alloy has been studied by computer-simulation and transmiss ion electron microscope observation. The kinetic equation was derived from a general equation for the free energy of the system where the or dering and disordering undergo congruently. The excess free energy due to ordering was expressed by a Ginzburg-Landau type expansion, and th e boundary energy was assumed to be proportional to the second derivat ives of S-r and S-r(2), where S-r is the local degree of order at the position r in the system. The simulation was carried out for the annih ilation process of flat antiphase boundaries which were arranged perio dically, and the characteristic patterns of antiphase boundaries obser ved with an electron microscope were reproduced successfully.